Tim & Vicki Reiner in a Far Place
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P.O. Box 308011 Cleveland, OH 44130-8011 USA (440)826-3930
Baptist Mid-Missions of Canada 187 McLaughlin Drive ٠ Moncton, NB ٠ E1A4P4 (506)386-6601
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Due to our location in Brazil, whenever we
donate blood in the U.S., it is checked for
Chagas Disease (also known as American
trypanosomiasis). People in our area are
susceptible to this chronic tropical
parasitic malady caused by the flagellate
protozoan Trypanosoma cruzi.
Over 100 years ago, an innovative Brazilian physician,
Carlos Justiniano Ribeiro Chagas, the son of coffee
farmers, successfully led in the research of malaria and
yellow fever. Brazil´s Central Railroad Company invited him
in 1908 to a “boisterous railroad worker town at the end of
the new railroad line across Brazil, where migrant workers
were dying from what was thought to be malaria.”
It did not take him long to find that some of the symptoms
of this disease were different from malaria. By 1909, he
had compared the blood of the ill workers with the
parasites living in the vinchuca or barbeiro bug. He was
able to prove the transmission of the parasite with
marmoset monkeys bitten by the insect. He also found
that the barbeiros do not like light, and prefer to live and
lay their eggs in the unfinished walls of the homes of poor
Brazilians. On April 23, 1909, Dr. Chagas found the parasite
in a three year old girl. He went on to diagnose other cases
and performed over 100 autopsies on patients with similar
symptoms.
This parasite is usually transmitted to humans and other animals by blood-sucking insects of the
subfamily Triatominae, family Reduviidae, most commonly belonging to the genera Triatoma,
Rhodnius, or Panstrongylus. All barbeiros are hatched from the elongated whitish eggs free from
parasites, even if their parents have them. They only get T. cruzi from feeding on an infected animal or
human. Using its proboscis, a barbeiro takes 10 to 20 minutes to ingest a meal of blood from its resting
prey. Immediately after feeding, it defecates releasing the parasites. The sting is not painful and itches
afterwards. The disease enters through the opening in the skin. It may also be spread through blood
transfusion, organ transplant, ingestion of contaminated food, and from mother to fetus.
Because of the two phases of illness, the
disease can go undetected for twenty to
thirty years from the acute stage
(infection with a mild fever, fatigue and
vomiting) to the more serious chronic
stage. All the while, T. cruzi severely and
irreparably damages the internal organs.
“The symptoms of Chagas disease vary
over the course of an infection. In the
early, acute stage, symptoms are mild and
… responsive to antiparasitic treatments,
with 60–90% cure rates. After 4–8 weeks,
individuals with active infections enter the
chronic phase of Chagas disease that is
asymptomatic for 60–80% of chronically
infected individuals through their lifetime.
The antiparasitic treatments also appear to
delay or prevent the development of
disease symptoms during the chronic phase
of the disease, but 20–40% of chronically
infected individuals will still eventually
develop life-threatening heart and digestive
system disorders. The currently available
antiparasitic treatments for Chagas disease
are benznidazole and nifurtimox, which can
cause temporary side effects in many
patients including skin disorders, brain
toxicity, and digestive system irritation.
“Chagas disease is contracted primarily in the Americas, particularly in poor, rural areas of
Mexico, Central America, and South America; very rarely, the disease has originated in the
Southern United States. The insects that spread the disease are known by various local
names, including vinchuca in Argentina, Bolivia, Chile and Paraguay, barbeiro (the barber) in
Brazil, pito in Colombia, chinche in Central America, chipo in Venezuela, chupança, chinchorro,
and "the kissing bug". It is estimated that as many as 8 to 11 million people in Mexico, Central
America, and South America have Chagas disease, most of whom do not know they are
infected. Large-scale population movements from rural to urban areas of Latin America and
to other regions of the world have increased the geographic distribution of Chagas
disease...”
“In December [2006] as a precautionary measure the U.S. Food and Drug Administration
(FDA) approved a test suitable for widespread screening. Blood banks have now begun
systematically checking their supplies for the Chagas parasite. This new test identifies
infected donors and therefore can reduce the risk of disease transmission through blood
transfusion or organ transplantation.
“Concerns about Chagas disease have increased due to increase in the number of U.S.
residents who previously lived in countries where the infection is common.”
In Brazil, the war against barbeiros is mainly carried out by government
agencies like SUCAM, SUCEN and the Secretary of Health. The two main
strategies are (1) insecticide, and (2) adequately finishing wall surfaces so
insects have no place to hide. The job is enormous. Major progress has been
made in Brazil and several other Latin American countries to reduce the
number of cases. In more than 500 Brazilian municipalities, SUCAM sends
agents house to house with a supply of insecticide where they apply it to
eliminate the possibility of infestation.
Endemic Zones for Chagas Disease in Latin America
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Dr. Carlos Chagas (with hat, to rt of door) with railroad crew at the house where he was first shown barbeiros in 1908.
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