Apresenta

1
ORAL HISTORY AND TRANSMISSION OF CHAGAS DISEASE
UNFOLDING AN EPIDEMIOLOGICAL PUZZLE
2
In the eastern part of the State of Piauí,
northeast Brazil,the National Park of Serra da
Capivara with a surface area of 130.000 ha,
protects a zone of virgin caatinga vegetation and
numerous archaeological sites. This region,
today with a low population density, is one of
the few remaining areas of preserved caatinga in
Brazil. Predominant vegetation is arboreal with
some species from the Amazon Forest type,
defining a transition zone. The climate is dry,
semi-arid, with a rainy season (winter) from
october/november to february/march. There are no
rains in the rest of the year. Fauna is mainly
represented by mammals of medium and small size
(felines, wild rodents, armadillos, and
ant-eaters, these last ones almost extinct),
snakes (bell-snakes and corals), scorpions,
numerous insects and birds. (Pessis, 1991)
3
Four counties have part of their area included in
the National Park, with an estimated population
of approximately 35000 of which 24000 live in São
Raimundo Nonato whose urban area is the largest
in southeast Piauí. Outside the urban area, most
of the population lives in small villages without
urban equipments such as sewage and waste
disposal. Water is provided mainly from deep
wells sometimes distant up to 5 km from the
houses. Transportation is on foot or with the use
of small equines (jegues), today considered
typical of the northeast having been introduced
since colonial times. Until a few years ago, only
Coronel José Dias, which is the county nearest to
the main entrance to the Park, benefited from
electricity, water treatment and schools
established by the administration of the Park in
some localities.
4
In the beginning of 1999, we started our work in
the county of João Costa in the northern limits
of the Park. Our purpose was to establish a basic
diagnosis of the area in order to define
parameters for the follow up of health conditions
and identify risk factors from the
epidemiological point of view. The chosen study
county has a total area of 1870 km2 and an
estimated population for 1998 of 2740, with
almost 38 under 15 years of age and only 13
over 50. Since there was no consistent data on
health for this area and no regular medical
assistance, before defining the study design we
decided to make a first contact to have an
overall impression and to hear from people about
their health needs and expectations.
5
At that time, we found a large number of
Triatoma brasiliensis, an insect vector of Chagas
disease (American trypanosomiasis), inside the
houses. At that time the data from the Ministry
of Health did not register the area as of
possible transmission of Chagas disease and the
species found, which is native to the area, was
not expected to be adapted to the human
household. This situation imposed the need to
better understand the risk of transmission of
Chagas disease in João Costa and the present
situation of the population relative to this
infection.
6
The study design was an epidemiological
investigation to establish factors, biological
and social, related to the possible endemicity of
the disease. Fieldwork was done from march 1999
to september 2000 in six moments for a total of
ten weeks. The study included a blood sample
survey in all residents over 6 months of age.
Results did not indicate active transmission at
the moment of the study but prevalence of
infection was high ( 9,9). Considering only the
population over 20, prevalence rose to 17,9, and
above 40 years of age, positives were over 50.
The results indicated previous active
transmission in the area especially involving
people born between 1910 and 1960. General
conditions of transmission seemed to be unchanged
at least since 1911 when the Neiva and Penna
expediction crossed this area and described the
insect vector and cases compatible with diagnosis
of Chagas disease (Neiva Penna, 1916).
7
Why there was no present transmission if all
favorable conditions seemed to be present and
unchanged over so many years ? We decided to
enlarge our search for historical studies of that
area, although understanding that we would
probably face difficulties in dealing with
different focuses and dimensions of both space
and time. As we already knew we would probably
not have much luck in searching for small
events that could be meaningful to us in written
documents, and we decided to interview the elder
residents. Interviews were recorded with a
standard tape recorder and properly identified as
to place, date, time and name of the interviewed.
8
In the interview, after being asked to state
name, place and date of birth, people were asked
to tell about their lives, if they were married,
had children, their work, common diseases, what
they knew of the history of João Costa. Questions
were made to stimulate talking and put people at
ease. As much as possible no one was interrupted
when was talking about whatever they wanted. At
some time during the interview, people were asked
if they remembered since when there were bicudos
inside the houses. We felt free to ask this since
the presence of the insects is a constant
complain of the population to the health agents.
Analysis of the interviews were made trying to
identify recurrent information on the history of
João Costa and on the personal trajectories that
could give us clues as to what had happened
somewhere between 1910 and 1960 that could be
coherent with a rise in the risk of infection
with the parasite of Chagas disease.
9
In the interview, after being asked to state
name, place and date of birth, people were asked
to tell about their lives, if they were married,
had children, their work, common diseases, what
they knew of the history of João Costa. Questions
were made to stimulate talking and put people at
ease. As much as possible no one was interrupted
when was talking about whatever they wanted. At
some time during the interview, people were asked
if they remembered since when there were bicudos
inside the houses. We felt free to ask this since
the presence of the insects is a constant
complain of the population to the health agents.
Analysis of the interviews were made trying to
identify recurrent information on the history of
João Costa and on the personal trajectories that
could give us clues as to what had happened
somewhere between 1910 and 1960 that could be
coherent with a rise in the risk of infection
with the parasite of Chagas disease.
10
In the search for historical and anthropological
works referred to the study area we identified
the works of Mott,1977 and 1978, on the history
of occupation of southeast Piauí from the XVII to
the XX century and most important to us, those of
Queiroz,1994 and Godoi,1999. Queiroz describes
the economic relevance of the rubber produced
from maniçoba (Manihot piauhyensis) in this
region from the beginning of the XX century up to
the 1920s. This had also been mentioned by Neiva
Penna in 1912 who said that there pratically
there are no roads and the only one that deserves
this name was built recently between São Raimundo
and Remanso (in Bahia) by the company that
exploits the large maniçoba plantation there.
(Neiva Penna, 1916, p.171) .
11
Godoi, 1999, through oral history, identifies the
origins of a settlement near São Raimundo (in the
southern area of the Park) linked to the boom of
the maniçoba They came with the influence of
maniçoba, for the word spread that much money was
rolling here the coming of many people from
Pernambuco was with the maniçoba, around 1910 to
1914 before the maniçoba there was only the
family of Vitorino (Godoi, 1999, p. 55)
12
In our interviews there is no mention of any
period of significant entrance of imigrants
witnessed by the informers being constantly
affirmed that a few families are in the origin of
the county and that most people are
relatives   Everyone here has a relationship,
one family inside the other. That is, practically
everybody is a relative. It is difficult to see a
young man greeting an older one and not calling
him uncle. Not because it is typical, or
practical, or a habit, but because they are
really relatives. The people here is practically
just one family ( J.M.N., 42, speaker of the
local radio)
13
But the extraction of the maniçoba latex is
mentioned and the activity, contrary to what has
happened in São Raimundo, seems to have involved
only the exploitation of native plants.This was
an important clue to an activity in the area that
could have raised the risk of transmission since
the extraction of the latex from native plants
often involved entering the areas of rock
shelters and staying there at night. In these
areas, even today, there is active transmission
of the infection that circulates in the insect
vectors and a species of wild rodent (mocó), very
common in the rocks up in the plateau. The
interviews also point to a much longer permanence
of the activity in João Costa, probably being
present continuously from the 1910s to the early
1960s. Queiroz, 1994, points out that the
extraction of maniçoba that had practically
disappeared in the early 1920s in most of Piauí,
had a new rise during World War II
14
The people called xiringa, but the real name
is maniçoba. Up in the rocks. We took water to
spend a week. got some 20, 25kg in two of us!
We went to make the holes,. drive the hole in
the maniçoba, put the vase, the milk dripped
inside. With eight days we took it. Then,
washed, very well washed in water, and then went
to sell. It took some four, five hours up to the
plateau (the rocks) We camped there, we ate
armadillo, the dogs hunted.. Today nobody hunts
anymore, the IBAMA does not permitI made holes
in the maniçoba up to the age of 25 and today I
am on my 77 years and 6 months and 19 days,
today.Right here in João Costa nobody planted
maniçoba. I heard that perhaps, in the
begginning some people planted. But that was not
on my time People took it from the middle of the
bush, we slept there, in a shelter made of clay.
Scorpions too, and the bicudo there were too
many Those that slept in the ground they would
bite for sure. Many people here worked in the
maniçoba, yes The money we got was only from
maniçoba.It was seven, eight months only in the
maniçoba. We sold to Dorim.. He lived in São
João and put his buyer to buy and resell there,
gaining money (S.G.S., 77 years old)