What Impact Does Chagas Disease Have on Workforce Productivity in Latin America?

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What impact does Chagas disease have on
workforce productivity in Latin America?
Briefing Paper
MBAX 5151
What impact does Chagas disease have on workforce productivity in Latin America?
In order to understand the full impact of Chagas Disease in Latin America, it is first
prudent to understand a little of the epidemiology and protozoan characteristics of this
infectious agent. Chagas disease is a zoonosis causing heart disease, transmitted by the
parasite Trypanosoma cruzi in an insect vector. Chagas disease is the world’s leading
cause of heart disease and is endemic in Latin America. The disease is spread by either
blood transfusion or with the bite and defecation of the reduviid or “kissing bug” (see
Figure 1), so named for its tendency to attack around the lips of humans. It has been
estimated that 16-18 million people are infected with Chagas disease and about 100
million people are at risk of contracting the disease. This includes approximately 25% of
the population of Latin America. Chagas disease is estimated to cause 50,000 deaths per
year. Chagas disease is often associated with the health risk of poor housing. High
transmission rates of Chagas disease are strongly correlated with poor and overcrowded
housing, particularly where construction utilizes local natural materials such as wood, mud,
and thatch. The reduviid bug lives in the cracks of walls, dirt or wooden floors, and
furniture.
Figure1:
Symptoms
There are two stages of infection with Chagas disease. Acute symptoms only occur
in about 1% of cases. These appear one to two weeks after infection and include fever,
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facial swelling around the bite site, and enlarged and painful lymph glands, accompanied
with fatigue. In general, the symptoms last four to eight weeks and then disappear. In
about one-third of the acute cases, chronic symptoms develop ten-twenty years after
infection. These are cardiac problems, including an enlarged heart, altered heart rate or
rhythm, heart failure, or cardiac arrest. Enlargement of the esophagus or colon may also
occur, with concomitant nutritional problems. Severe chronic disease leads to death.
Rural Migration
Intense economic and social changes over the past four decades are stimulating
rural – urban migration in most of the endemic areas, with more than 60% of the
population presently settled in urban areas. Estimates are that chagasic patients are
migrating northward to the USA and even eastward to Europe. In addition, it is estimated
that 100,000 infected individuals are living in the USA, most of who immigrated from
Mexico and Central America. The infectious risk these individuals pose to non-endemic
areas is mainly through blood transfusion. The infectious individual, not knowing they have
been infected, donates a unit of blood and then that unit of blood is transfused to another
individual, transfusing not only the blood but also the Chagas protozoan infection.
Productivity Impact of Chagas Disease
It is estimated 752,000 working days per year are lost due to premature deaths caused by
Chagas disease in just the seven southernmost American countries. This corresponds to a
cost of $ 1.2 Billion dollars per year in lost productivity. In addition to the lost productivity,
the medical costs to treat infected individuals who develop severe cardiac or digestive
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chronic involvement is several times this amount. A study specific to Brazilian
absenteeism of chagasic workers represented an estimated minimum loss of $5.6 Million
per year. In most effected countries both genders work but since the disease results in a
disability, the infected become a financial burden to their family, which reduces, their
quality of life. Figure 2 below provides a good illustration of Chagas disease endemic
areas.
Figure 2:
Solutions
The most important solution to Chagas disease is prevention and control. The
World Health Organization (WHO) has targeted two specific strategies to eliminate this
disease.
1) Treatment of homes with insecticides to kill vectors and interrupt vectorial transmission
in the Southern Americas.
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2) Blood screening to prevent transmission through transfusion.
Implementation of these prevention and control strategies have been highly successful as
the incidence of infection from 1980 – 2000 has decreased significantly in several
countries (Figure 3).
Figure 3:
Other strategies would also be beneficial in eradicating this disease but are not WHO
strategies:
(1) Drug treatment for acute, early, indeterminate and congenital cases
(2) Home improvement. Substituting plastered walls and a metal roof for adobewalled, thatch-roofed dwellings to render them unsuitable for colonization by
vectors.
(3) Provide education on Chagas disease.
(4) Routine Screening of all blood bank blood should be implemented in all endemic
countries.
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(5) Development of a cheap, simple, reliable blood test with high sensitivity and
specificity.
(6) Further development of drugs to cure chronic infection.
Conclusion
Chagas disease is responsible for lost productivity at an estimated cost of $ 1.2 Billion U.S.
dollars annually in Latin America. This does not represent all costs associated with the
disease, the medical treatment and decreased lost of living standards created by this
disease only compounds the total cost. Chagas disease can be eradicated, strategies
already implemented by the WHO have been very effective but further action is needed.
Greater investment in building appropriate housing and providing drug research and
treatment can not only improve the quality of life for people living in endemic areas but will
also have a direct correlation in reducing the productivity loss in Latin America caused by
this disease. In addition, developed countries should assess the risk of their blood
supplies and if warranted implement routine screening for Chagas in order to prevent
further transfusion transmission.
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References
Meltzer, M. (1998). American Journal of Tropical Medicine and Hygiene. Using disabilityadjusted life years to assess the economic impact of dengue in Puerto Rico:19841994. Retrieved February, 26, 2006 from the World Wide Web:
http://www.ajtmh.org/cgi/content/abstract/59/2/265
Seattle Biomedical Research Insititute. Chagas Disease. Retrieved February 26, 2006
from the World Wide Web: http://www.sbri.org/diseases/chagas.asp
Figueroa, J. (1999, December 31). CDC. Report of the Workgroup on Parasitic Diseases
Retrieved from the World Wide Web: http://www.cdc.gov/mmwr/preview/mmwrhtml
/su48a21.htm
World Health Organization, Chagas Disease. Retrieved February 26, 2006 from the World
Wide Web: http://www.paho.org/english/hcp/hct/dch/chagas.htm
Dias, J. (1992), ISBT. Epidemiology of Chagas Disease. Retrieved February 26, 2006
from the World Wide Web: http://www.dbbm.fiocruz.br/tropical/chagas/chapter4.html
Research and Training in Tropical Disease, Chagas Disease. Retrieved February 26, 2006
from the World Wide Web: http://www.who.int/tdr/diseases/chagas/default.htm
An Anthology on Women, Health and Environment: Housing and Shelter. Retrieved
February 26, 2006 from the World Wide Web: http://www.who.int/docstore/
peh/archives/ women/Womhouse.htm
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