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, Page 2 of 7 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 Page 3 of 7 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. Page 4 of 7 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. Page 5 of 7 (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. Page 6 of 7 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 Page 7 of 7