30 ANTI-AEDES AEGYPTI MEASURES IN BRAZIL

ROUTINE ORGANIZATION IN
URBAN CENTERS
Zoning

At the beginning of anti-aegypti work in any
city it has been customary to divide the area to
be covered into zones of such size that the in-
spector starting work on Monday morning may
complete all of his routine visits by Friday eve-
ning, leaving half or all of Saturday free for
return visits to houses found closed on the occa-
sion of the routine visit. Any time remaining
available on Saturday may be used for special
problems of the zone in accordance with orienta-
tion given by medical directors or the chief in-
spector.

The extent of the zone varies with the interval
between visits, the size and scatter of the
houses, the density of aegypti breeding, and the
training of the inspector. On an average it con-
tains about six hundred houses. The zone should
not be intersected by obstacles, such as rivers and
large uninhabited areas, if this can be avoided.
The real unit of the city is of course the block,
which in most cases has definite limits that
can be used to separate one zone from another.

The proper zoning of a city is a delicate matter
which requires careful initial study to distribute
equitably the work to be done, and repeated re-
vision to adjust it to changing conditions. The
procedure in zoning is as follows:

1. By using a stop watch and noting the time con-
sumed in the inspection of representative sam-
ples of different types of house, the average time
factor is established for each type. Small
thatched mud huts with little ground and few
containers can be inspected rapidly; houses of
two or more stories take more time than do one-
story buildings; and houses having large
grounds are the most time consuming of all.

2. A rapid but complete census is made, by blocks,
of the number of each type of house to be found.

3. The blocks in the city are numbered in series on
a large-scale map. At the four corners of each
block the number of the block is stencilled in
figures about two and one-half inches high ona
wall of a building in an easily visible position.
(If a new block should be formed after the sur-
vey, it receives the number of the block of which
it was a part, followed by a letter.)

 

4. Since initial work must be carried out on a
weekly cycle, the zones are formed by grouping,
on the basis of the house census, as many adja-
cent blocks as can be worked in 40 hours, or
five eight-hour days.

The time necessary for the inspection of a
block is determined by multiplying the number
of buildings of each type existing therein by the
average number of minutes required to inspect a
building of that type; the sum of these products,
plus the number of minutes necessary for the
inspector to walk between buildings, gives the
number of minutes allowed the inspector for
working that block in determining the size of his
zone.

At the beginning of an antilarval service, the
inspectors find many breeding foci to destroy
and much educational work to do, so that the
zones must be smaller than they can be later,
when mosquito breeding has been reduced and
the public has become accustomed to house in-
spections. Therefore, at the end of approxi-
mately six months of service it is wise to make a
survey of the zones and institute such modifica-
tions as are indicated. Owing to growth and
changes occurring in any city over a long period
of time such surveys should be repeated at inter-
vals of not less than one year.

Five or six zones are grouped into a district
with a district inspector in charge. The zone
number always consists of two or more figures,

‘the first one or two indicating the district to

which it belongs, the last indicating the order of
the zone in the district. Example: Zone 11 indi-
cates Zone No. 1 of the first district; Zone 46
indicates the sixth zone of the fourth district;
Zone 125 indicates the fifth zone of the twelfth
district.

Inspectors

The work of the zone inspector is the most im-
portant item purchased with the funds devoted
to anti-aegypti work. The Yellow Fever Service
must determine, by preliminary tests and ex-
aminations, that a prospective employee has
the qualities required of a zone inspector and
must, so long as he remains in the Service, check
the work he does, for often there is a great dif-
ference between capacity and productivity. The
ORGANIZATION IN URBAN CENTERS

applicants chosen to be trained should be men of
good physique between the ages of 20 and 30,
possessing ordinarily good eyesight as tested by
ability to read newsprint in a rather dark place,
being able to write legibly and to do ordinary
arithmetical calculations, and possessing no
characteristics which might cause the public to
object to their entering homes.

The work of the zone inspectors is supervised
and checked by district inspectors, who in turn
are responsible to the doctor in charge. In the
larger cities the doctor in charge is usually as-
sisted by a general inspector in the supervision
of the district inspectors’ work. The duties of the
general inspector are the supervision and orien-
tation of all the field personnel of the Anti-
aegypti Service. (This includes all employees
except doctors, office staff, and chauffeurs.)

The principal tasks of the general inspector
are:

1. To keep record of, and report daily to the
secretary, the presence or absence of each
member of the field staff.

2. To prepare and send to the director the daily
itinerary! of the Complementary Services (see
pp. 45-64).

3. To provide substitutes for absentees.

4. To assign apprentices to various districts for
training in the duties of inspector.

5. To supervise the Complementary and Special
(pp. 64-97) Services.

6. To check the work of the district inspectors
and verify whether they are taking due interest
in the problems of their districts, and whether
the results reported by them are trustworthy.

7. To superintend and check the inspectors’ work
in the zones as part of the checking of the dis-
trict inspectors’ work.

8. To submit for approval of the director pro-
posed modifications in the work of the zones of
the Complementary and Special Services.

9. To prepare notes on individual employees for
the permanent record of field personnel.

1 This form varies in different cities and may be modified
according to local conditions. In Recife, for example, the
form contains various sections in order to cover all the
Complementary Services. The district inspector responsible
for each service fills in the respective itinerary and hands
it to the general inspector, who sends copies of all itin-
eraries to the director. In the smaller cities the total itiner-
ary may be mapped out by the general inspector.

 

31

10. To choose and present to the director groups
of competent candidates for the field staff.

Inspection Methods

Various methods of organizing house inspec-
tions have been tried in Brazil, including the so-
called dragging (arrastao) or sweeping method,
in which a number of inspectors work together,
visiting different houses in the same block under
the eyes of the supervisor. This method requires
much more walking for the inspection of a given
number of houses than other methods, and since
the same inspector only accidentally visits any
given house in successive cycles, individual re-
sponsibility for past work cannot be fixed. In-
spectors have also worked in pairs, or worked
with a helper; but accumulated experience
shows conclusively that the best and most eco-
nomical work is done by dividing the area into
zones, each of which is worked by a single in-
spector who is individually responsible for the
conditions in his zone. Certain problems, espe-
cially in the larger cities, cannot be handled by a
lone worker without special equipment, and
these are met by special services directly under
the sector office.

To facilitate the orientation of the zone in-
spector in the field and the careful checking of
his work by his district chief, conventional signs,
indicating the order in which the houses in the
block are being visited, are painted on a wall at
each street corner, together with the block num-
ber. For example: ‘‘Block No. 105” will be marked
<@@ 105 @ at the corner where work in the block
must begin, and simply <@] 105 (without the
dot) on the other corners of the same block. The
dot following the block number indicates the
building at which the inspector commences his
visits, and the vertex of the triangle indicates the
direction the inspector must follow in working
round the block. In badly defined blocks, the
signal @ <q is used to mark the last building
belonging to the block. Where blacks are exten-
sive, or where the position of the houses makes
it difficult to find the number of the block at the
corners, this number is painted on houses other
than those at the corners.

Since the zone is composed of complete blocks
which have signs indicating the course to be
32 ANTI-AEDES AEGYPTI MEASURES IN BRAZIL

followed by the inspector, the written itinerary
for the week’s work is reduced to a simple list of
blocks in the order in which they are to be in-
spected on the different days of the week. The
inspector is given an itinerary by numbered
blocks covering his zone, with indication as to
each day’s stint as well as a map showing the
location of the blocks of his zone. The district
inspector, who is responsible for checking the
work of five or six zones, carries a complete itin-
erary of his district and a map of each one of the
zones for which he is responsible.

The motorcar used by the doctor in charge is
provided with a map of the city showing the lo-
cation of each numbered block and the grouping
of blocks into zone districts, with complete itin-
eraries of all inspectors of the city. The car also
carries a list of points in the different districts
where the inspectors meet with the district in-
spector at the beginning and at the end of the
day’s work.

To impress upon the inspector the importance
of carrying out every detail of the work assigned
to him on every round of visits, and to facilitate
the continuous checking of his work, a fixed
itinerary is plotted out for each zone inspector,
any deviations from which must be reported in
writing. An example of a zone itinerary is given
below:

ZONE ITINERARY
FIRST DISTRICT—RECIFE
Meeting Place: Rua José Rufino No. 1061
Zone 11—Building 838

Days Blocks

Monday 1, 2, 3

Tuesday 3, 11, 12, 13, 14
Wednesday 15, 16, 17, 18, 19, 21, 22, 23
Thursday 23, 24, 25, 26, 27, 28, 29, 30
Friday 31, 32

Saturday Closed houses

In the large cities similar fixed itineraries are
established for the Complementary and Special
Services. The following is one day’s itinerary of
the Maritime Service in Recife, Pernambuco:

Monday : Dock workshops, Campina (the limit be-
ing the left of the railway), covering ironwork, cranes,
buildings, and galleries up to Warehouse “A.” From
Warehouse ‘“‘A” to Gyratory Bridge, covering iron-
work, cranes, warehouses, buildings, galleries, and

 

shipping alongside. Campina, the Old Customs House
Docks up to Mauricio de Nassau Bridge, covering
ironwork, buildings, and boats in repair.

The point at which each inspector begins work
each day is marked with a pin on a map at dis-
trict headquarters, and thus an inspector can be
found at any time even if his routine had been
interrupted by bad weather or holidays. This
map is a valuable check on the inspector and
leaves no margin for excuses if he is not found in
his zone.

The district inspector leaves his itinerary for
the day in a sealed envelope at the district head-
quarters. This itinerary indicates the zone and
blocks which he intends to visit and also the
approximate hour of each visit. Should the doc-
tor in charge care to find the district inspector to
check his work, he breaks the seal on the en-
velope containing the itinerary and countersigns
the envelope to let the district inspector know
that it was not opened by one of the inspectors.

For a proper recording of work done, begin-
ning with the Inspector’s Work Sheet, and es-
pecially for the careful checking of the work of
the zone inspector by the district inspector, it is
essential that every house have a number by
which it may be promptly identified.

In so far as a regular official system of num-
bering exists, it is respected and used as the basis
of assigning numbers to houses which lack them.
The inspector carries a heavy lumberman’s wax
pencil and marks the new house numbers clearly
in figures about two and one-half inches high on
any easily visible part of the front of the houses,
respecting as far as possible the desires of the oc-
cupants. Numbers are not written on doors or
windows, since they would be invisible from the
street when these were open.

The officer in charge of antilarval work must
always remember that the efficiency of this serv-
ice depends, in the final analysis, on the work of
the zone inspector.

The so-called Complementary and Special
Services take over certain problems which
could be handled by the zone inspector only with
great loss in time and energy. These services are
truly complementary and do not relieve the in-
spector of any of his responsibility for the condi-
tions in his zone. For example, the Adult Capture
10”

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General Inspector

District Inspector

District Inspector: Captures

District Inspector: Producing Focus

Fic. 9. Flags of the general inspector and the district inspectors of the Yellow Fever Service.
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Zone Inspector

Zone Inspector: Captures

Zone Inspector: Producing Focus

Zone Inspector: Vacant House

Fic. 10. Flags of zone inspectors of the Yellow Fever Service.
ORGANIZATION IN URBAN CENTERS 35

and Producing Focus Services are of little value
until a relatively low aegypti index has been ob-
tained by the routine work of the inspector, but
they are essential to the final reduction of this
index to zero. Likewise, experience has shown
that legal sanctions can be used only after the
people become familiar with the object of the
Service through the house inspection and educa-
tional work of the zone inspector.

Special attention has been given to the prob-
lem of making the checking of the inspectors’
work as easy and as nearly automatic as possible.
It has been found good business to put a district
inspector over not more than five or six zone
inspectors. Since the district inspector is respon-
sible for checking the work of the zone inspectors
he becomes responsible for conditions in the en-
tire district. This personal responsibility for
conditions in each zone in his district makes it
impossible for him to protect negligent and in-
efficient inspectors; he must either report them
or take the rap himself when the general inspec-
tor, the health officer in charge, or someone of
the special services uncovers unsatisfactory con-
ditions in his district.

There are two types of check visits made by
the district inspector: one is for the purpose of
working with the zone inspector; the other is for
revision, or follow-up work. The reason for work-
ing with the zone inspector is to observe his
technique and correct any faults which he may
have. This is especially important in newly or-
ganized services and when inspectors are inex-
perienced. In dealing with experienced inspectors
there is little need for this type of visit and re-
vision gives better results. The experienced in-
spector knows how to work well; the check visit
is made only to determine whether or not he is
doing so.

Revision consists of a reinspection of the
houses which have already been inspected. The
revision is made, preferably, not later than 24
hours after the inspector’s visit. If the check
visit of the district inspector is later than 24
hours after the inspector’s visit, it should not be
listed as a revision but as a “surprise visit” made
for the purpose of getting information regarding
conditions in the zone when an inspector is not
expected by the residents.

 

The use, in the written itinerary for each day
in the week, of the block numbers marked both
on the inspector’s spot map and on each block
corner of his zone enables the district inspector
to find the inspector’s flag at any time during
working hours, if he is at work. After the in-
spector is found on a check visit, his work for
the day is checked from his report (Form FA 2).
By visiting a few houses already noted as in-
spected, and examining the water containers in
them, the district inspector can decide whether
the inspector’s report is correct and whether he
has been working properly.

The Autograph House Visit Record (Form
FA 52), posted in every house inspected, enables
the district inspector to check the rounds of the
inspector against his itinerary. This form fails
to give a picture of the work done but does
oblige the inspector at least to enter the houses
on his itinerary for the day and record the date,
his name, and a note on the conditions found.
Form FA 52 is equally useful in checking the
visits reported by the district inspector, who is
obliged to initial this form on all houses visited.

No matter how complete the reports and sum-
maries of the inspectors’ work may be, they are
not a substitute for personal visits by the medi-
cal officer in charge. This officer therefore spends
only part of his time checking records in the
office and the rest of it in maintaining contact
with the field service by making a certain num-
ber of revision visits himself. Only thus can he
know the conditions under which his inspectors
work and whether their reports are being ade-
quately checked by the district inspectors.

Aegypti Indexes?

The larval, or breeding, index is used to fol-
low the progress of control measures over a pe-
riod in a given place and to compare roughly the
aegypti situation in different areas. Various cri-
teria have been used in calculating aegypti
indexes, but experience has shown that the most
useful of these for general purposes is the house
index. In calculating this index only two factors
are taken into consideration: the number of

1 Wherever the term “aegypti index,” “‘house index,”
“larval index,” or simply “index” is used the percentage
of houses found with foci is to be understood.
36 ANTI-AEDES AEGYPTI MEASURES IN BRAZIL

houses inspected and the number of these found
to have aegypti breeding foci. The house index
is the percentage of houses inspected found with
aegypti foci, irrespective of the dimensions of
the house, the size of the grounds on which it
stands, the number of containers found with
larvae, and the intensity of breeding noted. This
house index is referred to hereafter as the larval
index to distinguish it from the pupal index,
which is the percentage of houses inspected
found with pupal foci.
- In using indexes it must be remembered that
breeding indexes can never be translated directly
into terms of adult aegypti densities, which may
' wary widely at the same index level according to
local conditions. And yellow fever is transmitted
by adult mosquiotes and not by larval foci.
The house index has been criticized by some,
who insist that the house is not the unit in the
production of aegypti; for even though a house
may have imperfect roof gutters or other defects
which make the house itself a potential focus, the
majority of houses are not, in and of themselves,
breeding foci. This criticism overlooks the fact
that the house index is used not as a measure of
mosquito production but as a measure of the
distribution of aegypti breeding with relation to
the distribution of human population. Admit-
tedly, even for this purpose, the house index is
very imperfect, and valid conclusions cannot be
drawn without taking into consideration many
other sources of information. For this reason, the

Summary of Local Anti-aegypti Work (Form:

FA 14) carries a summary of all potential foci,
i.e., containers with. water as well as containers
with foci, arranged by type of container, and a
house index for each zone and for the town or
city covered by the report. This is important,

since it is possible to have a low total index for’

the city but a high index for some special type of
container or for one or more individual zones.
The aegypti index reported by the inspector,
plus that found by the medical officer and the
district inspector on their control visits, gives a
useful idea of conditions from week to week
until the area being worked becomes relatively
clean. The classification “relatively clean” can
be applied to an area in which the total index is
not over 5 per cent, and in which very few pupal

 

foci can be found by the inspector and the dis-
trict inspector.

The water-container indexes, or the percentages
of different potential breeding places in which
breeding is taking place, are of value in the initial
stages of the campaign to show the particular
type of container against which special measures
are needed in order to reduce the aegypti density
in an especially infested area. However, once the
service begins to function smoothly the house
index is found to be much more useful as a
measure of aegypti distribution in the com-
munity.

The female aegypti mosquito does not gen-
erally lay all her eggs at the same time, or in the
same water container; but on the other hand her
range of flight is limited. These factors both tend
to increase the value of the house index and to
lessen the relative value of the water-container
index.

The following routine is used for the registry
of indexes: “0” (zero) is used only when no
breeding whatever is found; any index between
0 and 0.05, even when based on only one aegypti
focus, irrespective of the number. of houses in-
spected, is represented by 0.0. The indexes from
0.05 to 0.14 are represented by 0.1. For noting
indexes on the various statistical forms (FA 14,
FA 14A, FA 69, FA 140, and FA 141, see pp. 109
to 119) the approximation of the first decimal
figure is used. When the second decimal figure is
below 5 the first one is retained; but when the
second decimal is 5 or more, the first decimal
figure is increased by one digit. Example: 0.33 is
registered as 0.3; 4.56 as 4.6; 0.95 as 1.0; 0.45 as
0.5; 4.73 as 4.7; 4.96 as 5.0. :

Indexes represent only the percentage of
houses, among those inspected, in which aegypti —
breeding was found and reported by the inspector.
The index can never give an idea of the size,
number, and productivity of the foci which were
found, or of the scatter of the houses in which
breeding was occurring; it can tell notHing re-
garding the distribution of breeding missed by
the inspector, or found by him but not reported.

The efficiency and imagination of the inspec-
tor are important factors in determining the
number of foci he discovers. The length of time
he has worked in the zone, and his honesty, are
 

  

 

 

 

 

 

 

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Fic. 12. Flag of Ditches and Wasteland Service (above), and of Maritime Service (below).

 

 
ORGANIZATION IN URBAN CENTERS 39

factors in determining the number he reports.
It is natural for an inspector assigned to a new
zone to be eager to report as many foci as pos-
sible to prove his activity and efficiency, since
he is not responsible for any foci previously
missed. As time passes he becomes reluctant to
report all foci found, as that might reflect on the
quality of his work.

The officer in charge of anti-aegypti work
should never be greatly surprised if, in a rela-
tively clean zone with a true low aegypti index,
he and his district inspector find, when visiting
houses with the zone inspector on his regular
inspection, double the number of foci usually
reported in the same number of houses when the
inspector works alone, and if reinspection or re-
vision of the zone inspector’s work reveals as
many additional foci as he reported for the same
houses. This is often due to the greater activity
and intelligence of the revising inspector rather
than to any dishonesty of the zone inspector.

Experience shows that the aegypti index may
vary with the day on which the inspection is
made. The people in the zone come to anticipate
the inspector’s visit on a certain day of the week
and clean out their water containers in prepara-
tion for his arrival. This destroys some larval
foci which might have given evidence of the
presence of producing foci in the neighborhood.
Any change in the inspector’s itinerary usually
brings with it an increase in the index, since his
visits are unexpected. The index based on the
routine work of the inspector gives no informa-
tion on foci which may have been cleaned up by
the occupants of the houses on the eve of his
regular visit. This is especially important to re-
member when surveys are being made in areas
where control measures have been discontinued.
Almost invariably such surveys show a dispro-
portionately high percentage of all foci found in
the first few houses inspected in each commu-
nity, before the news of the survey has spread.

After the first few weeks of work the produc-
tion of adult aegypti, on which the maintenance
of the species depends, comes from those foci
which the inspector fails to find, whereas the
aegypti index represents the foci found and re-
ported by him. During the initial stages of the
work many pupal foci are found, indicating adult

 

production; in the course of time the routine
inspection causes a great reduction in the total
number of foci found and a very marked and
exaggerated reduction in the number of pupal
foci found, as compared with foci of larvae only.
This is often due, in part, to the desire of the
inspector to cover up his previous failure to lo-
cate and destroy all foci in larval stages, since
pupae are very seldom found on weekly visits
except in foci missed on the previous visit. How-
ever, most of the disproportionate decrease of
pupal foci is due to the fact that the foci which
are easily found and destroyed on each visit of
the inspector never reach the pupal stage. It is
the repeatedly undiscovered foci which develop
and produce the adults; and these in turn lay
eggs in the accessible water deposits, forming the
larval foci which go to make up the inspector’s
regular aegypti index. The hidden pupal focus
which continues to produce adults is called a
“producing focus.” The hidden producing focus
is a most important factor in maintaining the
species in places where anti-aegypti measures
are in force, and a special service for its elimina-
tion has been organized, guided by the distribu-
tion of larval foci reported by the zone inspector
and by the distribution of adults reported by the
special Adult Capture Service.

In small towns of the interior there are rela-
tively few exceptional water containers of the
type which form hidden producing foci in the
cities; and most of the foci are easily accessible
to the inspector. In the large cities, and espe-
cially in the old ones, there are many hidden wa-
ter containers, such as abandoned wells, pits,
latrines, etc., which can be found only with real
effort and the use of some intelligence.

It was observed many years ago that yellow
fever disappeared from a city long before the
aegypti index was brought to zero, and that an
intensification of the anti-aegypti measures then
in use did not bring about the species eradication
of the vector. Under these conditions there was
no great profit in reducing the aegypti index very
much below the threshold at which yellow fever
disappeared. As long as anti-aegypti work con-
sisted of temporary campaigns for the elimina-
tion of yellow fever an extremely low index was
unnecessary and was even termed a “luxury
 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fic. 13. Support used for placing Yellow Fever Service flag on a building where an inspector is at work.
ORGANIZATION IN URBAN CENTERS 41

index.” The recognition in recent years of the
permanent threat of reinfection of cities, in-
herent in the existence of jungle yellow fever,
obliges the responsible authorities to organize
anti-aegypti measures on a permanent basis.
Factors which have made possible the eradica-
tion of the aegypti mosquito from numerous
Brazilian cities, counties, and even states, are:

1. The special Producing Focus Service for the
discovery and destruction of hidden pupal and
producing foci. This Service is effective in the
final stage of aegypti eradication in places where
the index has already been greatly reduced by
the efficient work of the zone inspector (see
pp. 81-89 for full details on this Service).

2. The special Adult Capture Service, which
checks on the presence of the aegypti mosquito
by searching for:and identifying adults caught
in houses (see pp. 89-97).

3. The routine application of a mixture of oils to
all water containers found breeding mosquitoes.

Oiling

Oiling not only kills aegypti larvae but causes
the destruction of the eggs adhering to the wall
of the container oiled above the water line. Dur-
ing anti-aegypti work in an area all mosquito
foci found by the inspectors are subjected to
routine oiling, with the exceptions mentioned
below:

1. Routine oiling is generally begun only after two
or three inspections have been made and the
householder has been advised, either by the
inspector or by means of a handbill left at the
house, that routine oiling of all containers with
foci will be undertaken on and after a given
date. During this initial period, before the routine
oiling is begun, foci are destroyed by empty-
ing the water from the offending container.
(This often fails to get rid of small larvae and of
course leaves the eggs on the walls, so that the
breeding is only interrupted and not prevented.)
When yellow fever exists in or threatens to in-
vade a locality, routine oiling of all containers
found with foci starts immediately during the
first inspection without previous notice.

2. Certain large containers, such as cisterns, which
are to be protected immediately by fish, are not
oiled, since oiling would make them unsuitable
for fish.

3. Certain large ground foci of mosquitoes, other

 

than aegypti, are not oiled when not of suffi-
cient importance to justify the cost.

4. Oiling may be omitted when the householder
prefers to destroy the offending container in the
presence of the inspector. (Strangely enough
some people develop such a deep-seated anti-
pathy to oiling that they prefer to destroy the
container even though it may have some value.)

5. Abandoned containers without value are de-
stroyed rather than oiled.

Routine oiling has been the most forceful
measure in persuading the householder to pro-
tect water containers from mosquitoes. Its puni-
tive action is direct and immediate and falls on
the person responsible for the care of the con-
tainers found with mosquito breeding. The oil
used in Brazil, a mixture of fuel and Diesel oils,
is disagreeable enough in taste and appearance
so that all containers oiled are thoroughly
washed out before renewed use; scrubbing of the
containers removes any eggs which may have
escaped the direct action of the oil. Thus it has
become axiomatic in Brazil that the only aegypti
breeding which resists routine oiling is that
which occurs in hidden, undiscovered, and hence
unoiled foci. However, oiling should be consid-
ered as an emergency or temporary measure to
be used only until such time as the container is
permanently protected.

Each zone inspector carries a flask or a can
with from approximately 300 cc. to one liter of
oil, according to local conditions. The Yellow
Fever Service mixture is excellent for preventing
aegypti breeding and is cheap, but it is not satis-
factory for use in spray pumps for outside oiling.
In Rio de Janeiro the inspector has a special liter
can with a spout and with a device for holding a
small flask of paste for putting up notices (see
Fig. 14, p. 42).

The inspector uses a stick with which to stir
the oiled water to insure thorough spreading of
the oil not only over the entire water surface but
also well up on the walls of the container. Such
stirring is better than the use of excessive
amounts of oil. It is difficult, at times impossible,
to get oil to form a film on the surface of water
which contains soap or certain fatty substances
even in very small quantitites. This difficulty is
encountered with highly volatile oils such as
42

gasoline and kerosene, as well as with fuel oil.
It must be taken into consideration before con-
demning an oil as unsatisfactory because of re-
ports that it does not spread easily.

 

KS

lh —o

——s»,

cms

i
|

 

| __._ Flask: 95x3 ems

 

 

——

Cis

om

oy

Fig. 14. Zone inspector’s oil can.

 

The larvicide used is a mixture of 75 per cent
Diesel oil with a specific gravity of approxi-
mately 0.861 at 60°F., and 25 per cent fuel oil
with a specific gravity of approximately 0.985 at
60°F. The resultant mixture gives:

Specific gravity at 60°F. 0.8916

Saybolt viscosity at 100°F. 53 seconds

Flash point, Pensky-Marten C. cup. 170°F.

Water and bottom sediment, ap- .

proximately ,

Should foci be too large to be oiled with the
supply carried by the inspector he makes out a
Note for Oiler (Form FA 66, opposite) and hands
it to the district inspector. These forms are
turned in daily and reissued to the Oiling Serv-
ice (see p. 50).

1 per cent

Inspection Cycle

Under favorable conditions, the development
of the aegypti mosquito from egg to adult takes

 

ANTI-AEDES AEGYPTI MEASURES IN BRAZIL

place in a period of seven to eight days, so that
anti-aegypti campaigns must be carried out on
a weekly cycle if the production of mosquitoes
is to be maintained at a low level in cities where
the breeding index is only “relatively” or
“safely’’ low from the standpoint of yellow fever
transmission.

When an aegypti index has been brought
down to zero, or very close to that point, it tends
to increase slowly, and under such conditions the
inspection cycle may be lengthened or com-
pletely suspended without any untoward results.

In places where a true zero index of aegypti
production has been achieved, reinfestation is
generally due to (1) the return to use of clay
vessels on the walls of which viable aegypti eggs
are still present; (2) importation of water jars
with aegypti eggs by families moving from
aegypti infested areas; (3) the introduction of
adult aegypti mosquitoes from infested areas,
especially by boat and by train.

 

 

 

 

 

ANTI-AEDES AEGYPTI SERVICE
NOTE FOR OILER
ZONE... eee cece eee eens Block.............--205-
Street... 0... cece eee eee e neces No.........-
Type of container... 0.0... ccc cece cece eects ence teeeeee
Date... cc ccc ese c cece cece eee e nee eeneeeeeetaces
Signature of Inspector
OILING
Date... cece cece cece eee e cece eee en cee eeteeeenenerenne
Signature of Oiler
Form FA 66

 

 

 
ORGANIZATION IN URBAN CENTERS 43

Where a very low, but not zero, aegypti index
has been achieved, the rate of increase of breed-
ing under a lengthened inspection cycle will de-
pend in part on the care with which the zone
inspectors have cleared their areas of potential
foci, but even more on the subsequent work of
the Adult Capture and Producing Focus Serv-
ices.

Lengthened inspection cycles and suspension
of routine house visits should never be author-
ized without provision for continued supervision
by the Adult Capture Service, and for a renewal
of house inspections should increased aegypti
breeding be found at any time which cannot be
eliminated by the Producing Focus Service.

Experience has shown that the adult index is
a much more sensitive measure of the aegypti
production in an area than is the larval or
breeding index, even when the larval index is
based on weekly inspections.

As has been emphasized above, breeding in-
dexes cannot be translated directly into terms of
adult density or adult production. Due allow-
ance must be made for the interval between vis-
its. The foci found by the inspector on his weekly
rounds never become producing foci, but part of
those found on a biweekly or a monthly visit
may have produced adults during the interval
between inspections. Once this interval becomes
greater than the period required for the evolu-
tion of the aquatic phases of the mosquito, the
foci found become potential producing foci
which may build up a greater adult density than
is possible from the hidden producing foci re-
sponsible for maintaining the species under the
weekly cycle of visits.

Adult indexes are more expensive to deter-
mine than larval indexes and need not be used
in places which are known to be infested or to be
only “relatively” clean. The adult index is, how-
ever, indispensable in estimating actual condi-
tions in areas believed to be infested and in areas
with lengthened inspection cycles or suspended
services.

As a preliminary to any lengthening of the in-
spection cycle in a large city, special care should
be taken to eliminate the final hidden foci
through the efforts of the Producing Focus Serv-
ice oriented by adult captures.

 

When the inspection cycle in a city is first
lengthened there should be no immediate reduc-
tion in personnel; zone inspectors made avail-
able by lengthening the cycle should be used to
reinforce the work of the Adult Capture and
Producing Focus Service until the aegypti mos-
quito is eradicated.

Statistical reports should be made on the basis
of a complete cycle of inspection, with an indi-
cation of the weeks of the year covered by each
report. For places worked on a 14-day cycle re-
ports are made every fortnight; for those on a
28-day cycle, every four weeks.

When various inspection cycles are employed
in different parts of the same city, as often hap-
pens (7 and 14, 14 and 28; 7, 14, and 28 days),
the summary report (Form FA 14) is prepared
only at intervals corresponding to the longest
cycle and carries data only for the last complete
cycle of visits in each part of the city. For exam-
ple, the report for a town, part of which is on a
14-day cycle and part on a 28-day cycle, sum-
marizes all data from all of the district inspec-
tors’ work sheets (Form FA 4) for that part on
a 28-day cycle, but only those data for the zones
on a 14-day cycle which refer to the last inspec-
tion. The summary of data for the first inspec-
tion in the section on a 14-day cycle is prepared
as a local report for the orientation of the local
director only.

In the interior, the lengthened inspection cycle
is feasible and essential to economical admin-
istration, but should be adopted only after a
thorough study of local conditions, taking into
consideration:

1. The actual aegypti index.

2. The behavior of the aegypti index (past fluctua-

tions).

3. Presence or absence of adult mosquitoes re-

ported by the Adult Capture Service.

4. Inspection reports of medical officers and dis-

trict inspectors.

5. The percentage of containers requiring fish,

which had been supplied with fish.

6. Number, nature, and condition of potential foci.

7. The aegypti index of neighboring areas from which

either adult mosquitoes or containers with eggs
and larvae might be imported to reinfest the area
for which a lengthened cycle is proposed. (Zero in-
dexes and lengthened cycles are most advan-
wee Ste

weortiee
eerie

eee

   

“VIEW IN PERSPECTIVE

LATERAL VIEW

 

   
 
   
       

 

 

    

Y

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

I< 2,50
| ee
A
8
cf
—.-¥.
DIAGRAM

Fic. 15. Tank used at fish depots of the Yellow Fever Service for receiving fish as they are purchased,
and for maintaining a reserve supply.
COMPLEMENTARY SERVICES 45

tageous when they exist simultaneously over an
entire region.)

8. Correlation of adult captures with the zone in-
spectors’ aegypti indexes.

It must be borne in mind that a lengthened
cycle of inspections is feasible only when guar-
anteed by routine oiling or destruction of each
and every water container found with larvae
and that a lengthened cycle is dangerous so long
as aegypti mosquitoes are present.

The local director must not alter the cycle
without previous authorization of the regional
director. The regional director shall submit for
the approval of the general director details of
plans for any general change in the length of
cycles in his region.

COMPLEMENTARY SERVICES IN
URBAN AREAS

The zone inspector’s work, as has previously
been stated, is the core of the anti-aegypti
measures. There are, however, certain problems
which cannot be handled advantageously by the
zone inspector, and Complementary Services
have been established to take care of these
problems. The inspectors of the Complementary
Services are carefully selected, are given special
training, and carry special equipment for their
tasks. Among the Complementary Services
which may be useful at times in the large urban
centers are:

. Fish Service

. Inaccessible Tank Service

. Cemetery Service

. Ditches and Wasteland Service
. Oiling Service

. Vacant House Service

a wh & bp

Fish Service

Larviphagous fish were widely used for the con-
trol of aegypti breeding before the enforcement
of routine oiling, with Diesel and fuel oil mixtures,
of all water containers found with evidence of
mosquito breeding. But the widespread use of
fish in small household containers proved very
costly and troublesome because of the high re-
placement rate, and it has been abandoned in
favor of oiling, which is more economical and
gives more immediate and more permanent re-

 

sults. Today, fish are used only for the easily
accessible large water containers in which they
can become self-sustaining, and where for special
reasons other methods of control cannot be used.
Most small species of fish, and the young of some
large species, are more or less larviphagous; the
selection of the species used depends on avail-
ability, adaptability to artificial containers,
hardihood, cost, facility of transportation, etc.

The species most commonly used by the Yel-
low Fever Service in Brazil are those popularly
known as “piabas”! and “barrigudinhos,” espe-
cially adapted to muddy or turbid water. In
some places “acaras” and “‘piads,” larger and
more sluggish fish, are used.

Fish are generally contracted for locally, the
price in Brazil ranging from $.50 to $1.50 per
thousand. In some places the price varies with
the species furnished. All payments are made
on the basis of the number of fish alive and well
24 hours after delivery to the fish tank of the
Yellow Fever Service. A receipt for fish received
(Form FA 107) is issued to the supplier 24 hours
after he has delivered them, with the number
which have died in the meantime deducted from
the total to be paid for. The accounting section
reports the number of fish purchased each month
in each locality. Where fish are easily secured,
and the aegypti index is low, the householder
gets fish from independent sources if he cares to
use them in order to avoid the oiling of his water
containers.

The life span of fish in domestic water con-
tainers depends to a great extent on the care
given them. In practice it has been found best
to have the householder, in whose container the
fish are to live, go or send to the fish depot for
the fish. Fish which have been fetched always
get better care than do those gratuitously dis-
tributed by the Service. The Service may make
direct distribution of fish to the home in the
initial stages of emergency campaigns in locali-
ties where rapid reduction of the aegypti index
is essential because of the presence, or threat, of
yellow fever. In this case they are not issued
against the Fish Requisition (Form FA 65), but

 

1 Popular names of fish vary from place to place and
several species may be grouped under a single name.
FISH DEPOT—WEEKLY REPORT

ANTI-AEDES AEGYPTI SERVICE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Type of depot... 0.0... cece cece eect cree cece rer ereteertecneeeetee State... ccc cece cece ence eee enee City. cc cece eee e cere ence er eceenee Week. ........ Week of year.........
Stock DELIVERED Stock
ROCATION atEnd | Stock | p4 for Price
of Checked. R Is ed Total S Per Fol- per Observations
Previous | Quantity | “°°*'Y €rv- | Public} Dead | Cent | Total} lowing | Thousand
Zone Street and No., or Town Week ice Dead Week
Total
Foum FA 106 Signature of Employee in Charge Signature of Director

 
COMPLEMENTARY SERVICES 47

 

are noted directly on
the Inspector’s Work

ANTI-AEDES AEGYPTI SERVICE

 

Sheet. The fish depots
are carefully super-
vised to guard against
falsification of the de-
livery records and to
prevent avoidable mor-
tality of the fish. The
fish are paid for only
on presentation of re-
ceipts from the keeper
of the depot (Form FA
107). The Fish Tank
Weekly Report (Form
FA 40) is filed rou-
tinely at all. depots,
whether tanks or bar-

rels, and the weekly | romFa 107

 

Fish depot at..:......0-000

Received........0eeeeeeeeee
eeseee  cevaveeseee..-Gead at end of 24 hours

sence ete eee eee eeeeeees total to be paid for

FISH RECEIPT

 

 

 

summary of these re-
ports is made regularly
on Form FA 106. De-
liveries are checked
against Form FA 107 and Form FA 65. Ob-
servance of the following rules is of value in
maintaining a low mortality among fish at the
depots:

1. Have plenty of clean water. A painted line a

hand’s breadth below the rim of the tank calls

attention to the need for adding water when it
falls below this level.

Wash tanks frequently and supply clean water.

. Do not crowd too many fish into a tank.

. Protect tanks against direct sunlight.

. Always handle fish gently and only when nec-
essary; handle only with a special net furnished
for this purpose.

6. Always provide small containers with a piece
of sewer pipe or broken tile under which the
fish may take shelter.

7. Remove dead fish immediately.

Ob Wh

The fish are transported in large buckets well
supplied with water. Not more than fifty fish
should be carried in each five-gallon tin. The
transportation of the fish should take place in
the coolest hours of the day, avoiding as much
as possible exposure to direct sunlight. Care
should be taken not to jar the tin, since violent
motion of the water may cause a high mortality.

 

Receipt issued to fishermen supplying fish to the Yellow Fever Service. Payment against
the receipt is made at the office of the Service.

After transfer from one place to another, or
from the central tank to the local depot, fish
should rest 24 hours before the final distribution.
To allow for this initial rest period, depot tanks
are divided into two sections and subsidiary
posts are generally provided with at least two
barrels.

The depot caretaker delivers fish only upon
presentation of the Fish Requisition (Form FA
65) and only in the number indicated by the in-
spector. The number and species of fish delivered
against each Form FA 65 is noted thereon and
this form is filed at the depot as a receipt for
fish delivered.

In supplying fish, care should be taken not to
distribute more than are required: one or two
fish are enough for most individual household
containers; and even wells, cisterns, and small
lagoons require only five to fifteen fish.

Large bodies of water, such as ditches and
lagoons, may be supplied with fish. In these
bodies of water the length of life of the fish de-
pends relatively little on the householder.

Where fish are used on a large scale the Serv-
ice maintains depots in various parts of the city,
each supplying an area having a radius of about
48

one and one-half miles. Barrels are inexpensive,
easily transported, and suitable as deposits for
fish in places where the turnover is small; several
barrels can be used where business is heavier.
The central depot generally has a special tank
for receiving fish as purchased and for maintain-
ing a reserve supply (see Fig. 15). This tank
can be cleaned easily without removing the fish.

 

ANTI-AEDES AEGYPTI SERVICE

 

FISH REQUISITION

Species of fish.......... 0... e cece eee c cen eeeeaeerarees
| Fype of container... 2.0... 02... eee ce eect e eee ees

Number of containers........0... 0.0. cccceucecuccacecens

 

The nearest fish tank is at

Street......0 0... c cece cece eee ee eee enna

 

DELIVERY

Form FA 65

 

 

 

The caretaker of the fish depot delivers fish on presenta-
tion of this requisition.

 

ANTI-AEDES AEGYPTI MEASURES IN BRAZIL

Inaccessible Tank Service

In cities where the water supply is not con-
stant throughout the day, it is customary for
houses to have one or more tanks which receive
water when it is available, and act as pressure
reservoirs when it is not. Regulations provide
that these tanks shall be so placed as to be easily
accessible to the zone inspector (Article 12 of
Decree No. 21,434 of May 23, 1932), but many
of those in old houses cannot be made acces-
sible without undue expense.

Water tanks are classified as:

1. Accessible to the zone inspector, when their
examination presents no special problems. Such
tanks are inspected by the zone inspector and re-
ported routinely on Form FA 2, and also under
“Containers”” on Form FA 14. In case a tank is
properly sealed, the inspector need not verify
whether it contains water or not but notes it on
Form FA 2 as “inspected”’ and ‘‘eliminated” as a
possible focus.

2. Inaccessible to the zone inspector, when, be-
cause of their height, a ladder is required for their
inspection. The inaccessible tanks are recapitulated
weekly under “B” on Form FA 15.

The number of inaccessible water tanks exist-
ing in his zone is periodically checked and re-
ported by the zone inspector on Form FA 105.
Whenever the zone inspector during his routine
visits finds an unregistered inaccessible water
tank, he notes it on his copy of Form FA 105
and also in his notebook, for reporting to the dis-
trict inspector. Similar notations are made when-
ever a water tank is destroyed or removed. On
the basis of the information contained on Form
FA 105 special inspectors of the Inaccessible
Tank Service are sent out.

The Inaccessible Tank Service is responsible
for knowing the number, location, and condition
of the water tanks which cannot be easily in-
spected by the zone inspector and for making
them mosquitoproof. Inaccessible tanks are
always sealed, as stocking with fish is unsatis-
factory because of the difficulty of inspection to
determine whether the fish are still alive. Only
where sealing is completely impossible are fish
used and then only after a screened overflow
pipe has been installed to prevent their being
carried over the top, and the outlet pipe has
INACCESSIBLE TANK SERVICE 49

 

ANTI-AEDES AEGYPTI SERVICE

 

FISH TANK—WEEKLY REPORT

 

 

 

FISH DELIVERED

Fish

 

Public Dead

Service

Total

Received Remarks

 

Mon.

 

Tue.

 

Wed.

 

Thu.

 

Fri.

 

Sat.

 

Total

 

 

 

 

 

 

 

Balance at end of last week........-0-0- eee eee

eee wt ere eee meee eae cera eee nar arses er nes

Fish received this week... ....-.eccee cee cence recent eaten ceeeeeeseessssssesssssstis

Fish delivered this week.......... 02 ce cece reer een e cee eeeeeerencceersssssssereses tits

Balance for next WeeK.. 0... cece ccc cece renee reer e een ene e tara c acne aces esse anes n ee ees

Form FA 40

 

 

 

In the column “Service” of this form are noted the fish delivered to employees of the
Yellow Fever Service for distribution, and in the column “Public” those delivered directly
to the householders at the depot. Under “Dead” are entered the number of fish that die
within 24 hours after delivery to the depot. The total of the column “Fish Received” must
agree with the number which appears against ““Total to be paid for” on Form FA 107. Fish
dying within 24 hours do not appear as “Fish Received.”

been screened and extended above the bottom
of the tank so that the water is never all drained
off. However, the Yellow Fever Service itself
makes no effort to seal tanks; experience has
shown that tanks sealed free of charge are
opened on the slightest pretext, whereas those
sealed by, and at the expense of, the householder
remain untouched for months or even years.

The method of sealing varies with the type of
tank. Sealing to be satisfactory must:

1. Offer an absolute guarantee against the entrance

of mosquitoes over a relatively long period of
time.

 

2. Be easily examined by the inspector on his rou-

tine visit.

3. Be easy to replace or repair.

Wooden covers are not acceptable, owing to
their tendency to warp and crack.

The inspector of the Inaccessible Tank Serv-
ice works with an assistant, who carries a ladder.
He carefully examines the cover and the sealing
of the tank, leaving a note of his visit and of con-
ditions found, on the Autograph House Visit
Record (Form FA 52), which must be pasted in
a prominent place on the tank itself. Similar
notes are made on Form FA 105. The following
50 ANTI-AEDES AEGYPTI MEASURES IN BRAZIL

abbreviations have been adopted to indicate the
condition of inaccessible tanks:

MP: Completely sealed and mosquitoproof.

C: Covered but not mosquitoproof.

F: With fish.

DIS: Disconnected. The word “disconnected” in-
dicates that the tank is completely empty
and that water cannot enter it.
Unprotected. This indicates that the tank is
open, contains or may receive water, and has
no protection whatsoever against mos-
quitoes.

UP:

Foci found are noted in the column “Inspec-
tions” on Form FA 105 and also on Form FA 2.
If the tank is not in satisfactory condition a Note
for Legal Summons (Form FA 63) is made out.
Although subsequent inspection, following the
delivery of the Note for Legal Summons may be
made by the inaccessible tank inspector, the re-
sults of these inspections are not recorded on
Form FA 105, which is reserved exclusively for
the survey or census inspection.

For the guidance of those responsible for seal-
ing tanks, the Service furnishes drawings (figs.
16 and 17), showing the best methods of closing
different types of tanks. The inspector, when fill-
ing out the Note for Legal Summons, indicates
whether the tank is of “A” or “B” type, as
shown on the drawings, and attaches the cor-
responding drawing to the form handed to the
householder.

When conditions in general are satisfactory,
almost all of the tanks mosquitoproof, and the
aegypti index of the area zero, the inspection
cycle is increased to a quarterly, a semiannual,
or an annual period. Inspection is often sus-
pended indefinitely in places where the Adult
Capture Service is checking the amount of adult
aegypti production.

Cemetery Service

In many cities cemeteries constitute a special
problem in antilarval work. The numerous
graves and tombs, adorned with vases, urns, and
jars of flowers, require careful inspection and
adequate control measures.

The Yellow Fever Service distributes printed
forms advising the public’ to use wet sand in-
stead of water in all cemetery vases and jars. In

 

some cemeteries photographs are displayed at
the entrance showing how the vases should be
filled with sand. Sand piles are placed at con-
venient points in the cemetery.

Large cemeteries are worked by a special in-
spector equipped as are the inspectors of the
Producing Focus Service and assisted by the
necessary number of helpers (servants, oilers,
etc.). He makes a thorough inspection for the
discovery and destruction of mosquito foci and
fills all vases with earth or sand. Annually, im-
mediately after All Souls’ Day, he makes a spe-
cial visit to replace the water in the vases with
wet sand.

In smaller cities, the cemeteries can be dealt
with efficiently by the zone inspector during his
routine visit.

Ditches and Wasteland Service

Cleaning ditches, cutting weeds on vacant
lots, clearing brush on wasteland, removing rub-
bish, etc., is the responsibility of the property
owners and to a certain extent of the municipal-
ity. Owners are warned to maintain their prop-
erties free of mosquito breeding, and the mu-
nicipality is reminded of its obligation to prevent
breeding on public lands and highways.

However, in certain emergencies the Yellow
Fever Service organizes a temporary gang of
men for the cleaning of ditches and wasteland.
The organization, previous authorization for
which is obtained from the sector director, and
the administration of such work are carried out
in accordance with local conditions in each case.

Oiling Service

In some places the Yellow Fever Service main-
tains oilers who use a spray pump of the “‘Pan-
ama” type. These oilers, in accordance with an
itinerary, carry out the routine oiling of certain
large breeding places, and also attend to the oil-
ing indicated on Form FA 66 handed in by the
inspector. When the oiler works on his itinerary
he uses the Inspector’s Work Sheet (Form FA 2)
to record the work done. Where there are ditches,
lakes, wells, pits, etc., requiring constant and
costly oiling, measures are taken as soon as pos-
sible to ensure their definite elimination. Legal
action is taken, when necessary, to oblige the
ANTI-AEDES AEGYPTI SERVICE
INACCESSIBLE TANK CENSUS AND INSPECTION RECORD

CHY ccc cece cece cece eee eneeneaseceneeeevenunucunvecsenceretaeues State. cc cc ccccccccccnc creer renee estes sees scene eet beeteeeteeessseteesesscee Date of census... .. 0... ccc eens sec ncseceeeaceteceessscsacecevceccutecevecesese

 

ADDRESS , INSPECTIONS

Street . Date Result Date Result Date Result Date Result Date Result Date Result

 

Form FA 105
 

 

TYPE "A"
WATER TANKS MADE OF REINFORCED CONCRETE MASONRY OR IRON

Cement lid made to prevent mosquito entry

 

 

 

 

*. Inlet pipe
NX Cement cover —
Permanent and fixed seal << \A
with cement em a
Nee —__ * “Cement seal
. . ement sea
Nu! 4 A
wv, weet

 

 

 

WATER TANK CONSTRUCTED OF REINFORCED CONCRETE OR MASONRY

 

       
  

 

Cover of cloth or fine wire netting yo nlet pipe
, 7. Metal cover, i
Permanent and = ~_Sofety outlet
fixed seal with _+- a J protected by
solder ———~_- Sealed with cloth_-- ine wire
netting.

Sealed with solder
cloth or mosquito |
netting

prec recewccce |

o”

 

  

 

 
 

Outlet pipe~ Autograph Visit Record

GALVANIZED (USUALLY) IRON WATER TANK

NOTE: Wooden covers are not acceptable

 

Fic. 16. Methods of mosquitoproofing concrete and iron water tanks.

 
 

 

TYPE "B"
WATER TANKS MADE FROM BARRELS AND DRUMS

Sofety outlet protected by
mosquito netting ~

 

 

 

   

HORIZONTAL. POSITION

j+——- inlet pipe

 

 

 

 

 

 

  

 

Fic. 17. Water tanks of the barrel and drum types, properly protected against mosquito entry.

 
 

ANTI-AEDES AEGYPTI SERVICE

OIL DEPOT—WEEKLY REPORT
POSE. ccc ccc cece cece tee ee ce eee ne tee eee eeereneneneees Municipality... 00... cece cece cece eee ees

 

 

Oil depot located at... 00... cece cece cence teen teen tetera teen eeees Street, No... 0... cece cece reece e enw

Week from ......... 00. ccc eee nee CO cece ccc ee eect nero

 

 

Date Quantity Issued to (Signature) Category

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Total. co.cc cece eee en eens District Inspector

Form FA 42

 

 

 
56 ANTI-AEDES AEGYPTI MEASURES IN BRAZIL

owners to correct unsatisfactory conditions, in-
stead of continuing with the oiling indefinitely.

Those superintending and checking the work
should foresee the possibility of an unscrupulous
oiler discharging the greater part of the contents
of the pump into the first few containers to be
oiled to lessen the weight of the pump, which
results in insufficient oiling of the remainder.

In order to facilitate oiling, a number of oil
depots are maintained at different points in the
control area where the inspectors and oilers can
obtain fresh supplies as needed. For the purpose
of checking the use of oil a record of receipt and
disbursement is kept at each depot in the cities
worked. This-Oil Depot Report (Form FA 42) is
made up weekly, the total of oil issued being
checked with Form FA 66 in order to verify
whether the quantity consumed is reasonable.

Oil sent to depots in the interior (where the
consumption is relatively small) is dispatched
in used five-gallon gasoline tins and not in
drums. These cans, full of oil of the type used
by the Yellow Fever Service, may be closed by
soldering without danger. Care is taken to en-
sure that the oil depots in the interior are never
without oil, and also that they are never greatly
overstocked, which might lead to waste.

The oil depots send a report on the last day
of the month to the sector or local office showing

the stock of oil on hand at the end of the preced-

ing month, the amount received during the
month, the amount issued, and the amount in
stock at the end of the current month.

The quantity of oil issued by the depot must
be frequently checked against the number and
type of containers oiled, as reported on Form
FA 14 submitted by the corresponding post.

Vacant House Service

The vacant house is differentiated from the
closed house. The vacant house is unfurnished
and unoccupied; the closed house is furnished
and occupied, with its occupants temporarily
absent.! The closed house is generally inspected

1Jn certain localities the summer vacation season finds
many houses closed, with their occupants in the mountains
or at the beach. Where the anti-aegypti work is well estab-
lished this problem can be handled by the zone inspector,
but in areas where the work is new he may require special
assistance.

 

by the regular zone inspector, whereas the va-
cant house is at times handled by a special in-
spector. The vacant house which has not been
made mosquitoproof is a dangerous source of
aegypti production where the antimosquito cam-
paign has not yet reduced the aegypti index toa
very low figure.

The poorer types of vacant houses can gen-
erally be visited by the zone inspector, since the
keys are usually with the neighbors. Where a
piped water supply does not exist or is not con-
nected the house often requires only a yard in-
spection. Vacant houses with a piped water
supply and connected with a sewerage system
are especially dangerous and must be very care-
fully inspected.

The work of the Vacant House Service is based
on a quarterly census of vacant houses made by
the inspector in each zone and recorded on Form
FA 59. In taking the census of vacant houses
the inspector includes only those he cannot work
easily on his regular routine visit. A copy of
Form FA 59 is made for the vacant house inspec-
tor, and the zone inspector keeps his copy up to
date by noting vacant houses which may be re-
occupied and occupied houses which become
vacant. The inspector reports such changes daily
through the district inspector so that the office
list and the vacant house inspector’s list can be
duly altered.

In small cities the Vacant House Service is
simple, but in large cities it becomes cumber-
some and inefficient if it is not handled by care-
fully trained personnel. In large cities a special
district inspector for the Vacant House Service
supervises, orients, and inspects the squads of
inspectors and procurers of keys. The district
inspector and the key-men generally ride bi-
cycles.

Getting the keys is the most difficult part of
the work. The inspector, at the time he lists a
house as “‘vacant,” makes every effort to note on
Form FA 59 the name and address of the person
holding the key. The key-man receives a list of
the houses for which keys are lacking and then
organizes his itinerary (Form FA 108), listing
the addresses of the holders of keys in the order
in which they can be most easily visited. He
leaves copies of this itinerary for the director
KEY
C—Under construction
I—By the inspector

R—Reoccupied
T—Torn down ANTLAEDES AEGYPTI SERVICE
VACANT HOUSE CENSUS

 

 

enneveorercere

OF ec essseeneeceneer ee eeeres to

 

 

UNINHABITED HOUSES Date

Vv;
Street Name of Owner or Agent acated

The vacant house census is made by the zone inspector and recorded on this form.

Form FA 59
VACANT HOUSE SERVICE 59

 

 

ANTI-AEDES AEGYPTI SERVICE

 

NOTICE

To the occupants of house No...........-

a ee

In order to facilitate the work of the Yellow Fever Service, the occupants of this
house are requested to leave the keys with some neighbor whenever they are to be absent,
so that the inspector’s visit may be made at the regular time and they may avoid the

penalty established by law.

A house which is vacant and cannot be inspected because the keys are not available,
or because of delay or refusal to deliver the keys, or because of any other difficulties cre-
ated by the holder of the keys, shall be sealed until after its inspection by the Yellow
Fever Service. In such cases measures shall be taken to enter and inspect the building
in the presence of a police officer, following which it shall be closed and again sealed.

(Article 5 of Decree No. 21,434.)

Form FA 43

 

Request for keys, posted by the inspector in a prominent place on a house regularly found closed.

and for the general inspector, to facilitate the
checking of his activities.

The key-man gives a receipt for each key
(Form FA 39) and puts an identification tag on
‘ the key (Form FA 38). The keys collected one
day are distributed on the morning of the fol-
lowing day to the special vacant house squads,
who inspect the corresponding houses and re-
turn the keys to the office on the same day so
they can be given back to their owners on the
next day. Only in special circumstances do keys
remain in the possession of the Service more
than 48 hours. In cases of urgency, inspections
are made and keys returned within a few hours.

When a key is returned, the recipient signs for

 

it on the reverse side of Form FA 38. This shows
that the key has been returned promptly and
serves as a protection against later claims that a
missing key has never been returned. Receipts
for returned keys are kept on file for three
months or more.

Owners may refuse to give the keys and pre-
fer to go to the house to open it at the hour
marked for the inspection. However, rarely is
the house open at the time agreed upon; and the
Service always insists on getting the key, except
when there are objects of great value in the
house. .

The purpose of the inspection of the vacant
house is not only to find and destroy existing

 
60 ANTI-AEDES AEGYPTI MEASURES IN BRAZIL

 

ANTI-AEDES AEGYPTI SERVICE
KEY RECEIPT

Received. ........cc cee ceecceeeeeeees keys of house at
No..... eee Street... 0. cece cece cece eee ere ee er ecees
At. ccceeeeee ALMi. cece cece eee erence tenes 19......
P.M. month day
Inspector... 2... cece eee cece e cece reece eee eereeae
Form FA 39

 

 

 

Receipt given to the person supplying the key of a vacant
house.

 

ANTI-AEDES AEGYPTI SERVICE

KEY TAG
ZONE... cece cece cece eee eeee Block... 0.0... ccc eee eee
Street... ccc cece cece eee nec e eet e eee eee No.......005

Form FA 38

 

Key obtained: Date... 0.0.0.0 c cece eee eee eee eee neee
Returned: Date.... 0.0.0... cece eect ec entree eer e eens

Signature of recipient
of returned key:

 

Form FA 38 (reverse)

 

 

Front and back of the identification tag for the key of a
vacant house.

 

foci but also to prepare the house so that it will
be free of mosquito breeding during a period of
at least 30 days.

The vacant house inspector works with a
helper. Each squad carries the following equip-
ment in addition to that carried by the zone
inspector.

Ladder

Shovel

Trowel

Three-liter tin of oil

Pail of paste or glue

Strips of old newspapers
Machete and iron hooks for lifting manholes
Rope

Cement

Cheap cotton cloth

Forms FA 45, FA 62, and FA 81

Work begins with the yard. Before entering
the house, the water is cut off. All worthless
water containers are collected, counted, and
buried; movable containers of value are placed
in such a position that water cannot collect in
them. Immovable containers are filled with
earth or sand. The bathroom is visited next.

The toilet is flushed, and the toilet basin is

oiled before being sealed. The chain of the flush
tank is rolled up and placed on the top of the
tank. The water tank is drained off, oiled, and
sealed. A request not to break the seals on the
toilet basin and tank until the house is occu-
pied (Form FA 81) is pasted on the door of the
bathroom and on the seat of the toilet basin.
One to four ounces of oil are poured down each
drain pipe.

Any pools of rain water found in the house are
covered with sand or earth, and the responsible
window or doorsill is plugged with paper; leaks in
the roof are repaired if possible. When there are
house defects of potential importance to mos-
quito breeding which cannot be easily corrected
by the inspector, he makes a note for the legal
summons of the owner. If stocking the tanks
or cisterns with fish is indicated, a requisition
for fish is prepared and given, with the house
key, to the fish distributor. If the house is near
a fish depot the inspector’s helper fetches the
fish immediately. The use of fish in vacant
houses must be limited to containers which can
ANTI-AEDES AEGYPTI SERVICE
KEY-MAN’S WORK SHEET

Address, Street, Number Reasons for Delay
i Departure

 

Signature of District Inspector............... Sesh eee tees eee ea sa sacsueseeeesassssesecsssrsese

Signature of Doctor... 0.0... . cc eee cece cence ene eee n ee eee ee eee teen Eee EE Denes

 

Signature of Inspector

Form FA 108
 

 

ANTI-AEDES AEGYPTI SERVICE
REPORT OF VACANT HOUSE INSPECTION

 

 

 

 

 

 

 

Zone.........20-- Block......... Street... 0... cece eee c eee eee eee No........... Floor. ...........
Keys left at... ccc ccc cece cece cee tenet a eben teen e reese nena ees atenes ‘Lake ences eeeenenee
Name of proprietor. ....... 6c cece nen n nets ene eee nee eet bent e teen e ee eben nen eees
Address of proprietor. 0.0... cece cece cee nce teen een ete nee ee ee ene enn nee een ence ener
Date of inspections. 0.0.0.0... ccc cece cece ene ene nee n een eee eee eee e estate nee ene eneeeeenees
REINSPECTION
Date of last inspection. ....... 0. ccc cece cee ene eee ene REE OEE DEE Cee eee ee ee een E eee ee EES
State of sealing done during last Visit ......... 0.00. c eee e cent ene e ence e tenance erent eter ensee eens
Water cut Off. 2.0... ccc eee eect erences Water tanks emptied... 0.0.0... cece ete eens
State of roof gutters............- 0c cece eee cece ee Water tanks sealed... 0... 6... cee cece eee eee ee
Containers buried... 0.0... cece ccc eee e eens Sanitary apparatus sealed. ..............00. cece ee
Containers put under shelter...............0.20005 Windows sealed........ wee cee n eee eeenenee
Fixed containers filled with sand ................0. Fish requested. ...... 2.0... ce cece cece er eeeeeees
Legal summons to. .... 2.0... ccc eee cee cere renee eee eee tet eee teen nent bee eens
; sprcies | AEGYPTI | Cont CONTAINERS

Containers Found Cont. Elimi- Cont. j Provided| Fish
with Water Inspected nated Oiled With with |Distribu-

F FP | FA | FAP Fish Fish ted

 

Inaccessible tanks

 

Vats and tanks

 

Clay vessels

 

Barrel, drums, tubs

 

Spec. art. cont.

 

Roof gutters

 

Trees and plants

 

Wells and pits

 

Other containers

 

 

 

 

Totals

 

 

 

 

 

 

 

 

 

 

In the space “Cont. Eliminated” show the number of sealed water tanks

 

Time of leaving last house............ 0. cece eee ecco eeeeeeeeeaeee
Time of arrival this house. ........... 0c cece cece eee e en eeeeeeeees

Time of leaving this house........... 00. ccceeecceeeersetesaceees

 

Zone Inspector
Form FA 62

 

The data from the column “Containers” on this form are included on Form FA 14. The number of
vacant houses inspected in all zones during the week, and their respective indexes, are included at the end
of the list of indexes of the zone on Form FA 14. Form FA 62 greatly facilitates the checking of the work
of the squad.

 
 

 

ANTI-AEDES AEGYPTI SERVICE
INSPECTION NOTE FOR VACANT HOUSE

 

 

Keys left at... 0... cece cece ne eee eee ene n nen en ene teen een eben sete be nen tnteteeenens
Name of proprietor....... 0... ccc c cece cece cee nee n nen edna nee n ed eee een eet ee eta neneenebetaee

Address of proprietor... 0... 0. ccc cence cc ene cee nen n eee n eee e ete setaeeeaeessetersseneteanere

 

 

. Hour Inspector’s Initials of
Inspections Date Ended Signature Controller

 

First

 

Second

 

Third

 

Fourth

 

Fifth

 

 

 

 

 

Sixth

 

Form FA 45

 

 

Form posted on a vacant house for the recording of inspections.

 

ANTI-AEDES AEGYPTI SERVICE

 

THIS SEALING HAS BEEN DONE BY THE ANTI-AEDES AEGYPTI SERVICE
TO PREVENT MOSQUITO BREEDING WHILE THE HOUSE IS VACANT

PLEASE DO NOT BREAK THE SEALS

 

UNTIL THE HOUSE IS OCCUPIED.

BREAKING THIS SEAL IS PUNISHABLE BY FINE (ARTICLES 3 and 10
OF DECREE NO. 21,434 of MAY 23, 1932)

Form FA 81

 

 

 

Seal for toilet basin, flush tank, and bathroom door of a vacant house.
64

be given immediate protection in no other way,
such as wells, cisterns in use, and large un-
covered tanks.

Roof gutters and roofs are inspected. Tins and
other rubbish on the roof are removed and
buried. Gutters are cleaned of all obstruction
and, if possible, corrected for defective slope.

Before leaving, the inspector fills in the Re-
port of Vacant House Inspection (Form FA 62)
in place of Form FA 2 and leaves an Inspection
Note for Vacant House (Form FA 45) pasted in
the house so that it is visible from the street,
preferably behind a clear window pane or at
some other place sheltered from rain and from
tampering. On reinspection a note is added to
the Form FA 45 already in the house. This form
aids the medical officer and the district inspector
in locating the squad at work, since a glance will
show whether the day’s inspection has been
noted. The form also shows the date on which
the house was last inspected.

In special cases where the Producing Focus
Service cannot complete a neighborhood search
because of one or more vacant houses, a note for
“urgent” inspection is sent to the Vacant House
Service. This Service finds the necessary keys
and makes the inspections, reporting them not
on Form FA 62 but to the Producing Focus
Service, which includes them on Form FA 58,
with a note stating that the work has been done
by the Vacant House Service.

The work of the Vacant House Service is so
widely scattered and so irregular that there is a
constant temptation for employees to shirk. The
work reported and the time spent on a given
job are subject to constant checking, as is also the
time spent in going from one house to another.
By comparing the time of visit noted on one bul-
letin and the distance between houses it is pos-
sible to detect time wasted. An intelligently
prepared itinerary is essential for efficient work.
By using a spot map of the city, houses to be
inspected can be listed on the itinerary in ac-
cordance with their location, and travel time
between houses can be kept at a minimum. The
itinerary for the collector of keys should be
plotted in the same way.

The interval between inspections of vacant
houses depends on the amount of aegypti breed-

 

ANTI-AEDES AEGYPTI MEASURES IN BRAZIL

ing in the area. Ordinarily a monthly cycle is
sufficient, but where the aegypti index, espe-
cially pupal, is high the cycle may be shortened
to a fortnight, particularly in those districts
where a large number of foci have been found.

Care is taken to see that houses whose keys
are easily obtained are not visited more often
than is necessary while houses for which keys
are difficult to get are neglected.

When conditions in a city improve, the cycle
of visits to vacant houses is increased to two or
three months or even suspended, with the previ-
ous authorization of the regional director. Sus-
pension of visits to vacant houses is conditioned
on a very low aegypti index and on the organiza-
tion of an efficient Adult Capture Service. Since
the aegypti hatching out in a vacant house go to
neighboring houses to feed, the existence of
breeding in vacant houses is revealed by the
Capture Service.