Model for Chagas’ Control in Bolivia

At a national planning meeting for Chagas’ control in La Paz in November 1990, Sensano’s project gained acceptance as an effective model for chagasic control to be used by other nongovernmental organizations (NGOs) in Bolivia.[47]Its attractiveness lay in its efficiency, effectiveness, low cost, and use of culturally accepted techniques.[48]

Primary health care is the primary objective of PBCM. Its goals, as ideally defined, are essential health care made universally accessible to individuals and families in the community, through their full participation and at a cost that the community and country can afford.[49]

Sensano had incorporated Chagas’ control into PBCM’s primary health care mission in 1989 for the Department of Chuquisaca. It wasn’t until 1991 that Chagas’ disease was even considered to be a part of primary health care in other parts of Bolivia. The Department of Chuquisaca is heavily infested with triatomine bugs and has a high percentage of infected chagasic patients: 78.4 percent of the houses are infested with vinchucas, 39.1 percent of the intradomiciliary vinchucas carried T. cruzi, as did 25.3 percent of the peridomiciliary insects (SOH/CCH 1994:19). Some 78 percent of the population tested in endemic rural areas were seropositive to Chagas’ disease, and 26.6 percent were children from one to four years of age (SOH/CCH 1994:22). In Chuquisaca 9.4 percent of the inhabitants have latrines, 51 percent have potable water, and 2 percent have electricity.

Earlier referred to as the Department of Sucre, Chuquisaca has a population of 451,722 (rural, 305,201; urban, 146,521) people, according to the 1992 census. It covers 51,524 square kilometers, with a density of 9.6 persons per square kilometer. The annual population growth rate in Chuquisaca is low, 1.47 percent, compared to other departments: La Paz (1.6 percent), Santa Cruz (4.10 percent), Tarija (2.81 percent), and Cochabamba (2.66 percent). This department consists of high plateaus and valleys gradually descending down the eastern slopes of the Cordillera Central of the Andes. These valleys range in altitude from 2,425 feet to 9,200 feet above sea level. The fertile lands produce cereals, fruits, and vegetables and traditionally supplied the miners of Potosi with food.

Epidemiologists conducted studies in four communities where PBCM started Chagas’ control projects to assess the rate of infestation and infection with Chagas’ disease (see Appendix 14: Baseline Studies in Chuquisaca). Ninety percent of houses in the four communities were infested with vinchucas; 61 percent of these were transmitting the chagasic parasite (see Appendix 14, Table 5). Houses were classified as good, regular, and bad according to such factors as having straw and mud roofs; adobe walls partially plastered or without plaster; presence of cracks in walls, foundation, and roof; no ceiling; dirt floors; and poor hygiene (see Appendix 14, Table 6). The majority of the houses were found to be in poor condition and infested with vinchucas; a very high percentage of the population had Chagas’ disease. Unhealthy houses correlate closely with infestation rates, both being about 90 percent. This being the case, in endemic areas housing conditions alone could serve as indicators of infestation rates.

Chagas’ control projects are not easily incorporated into primary health care systems because of conflicting interests and inefficiency. A frequent conflict is that funding sources or advising institutions may be different: one organization may be responsible for primary health care, another funded for Chagas’ disease control. Programs have to work together. Other possible infrastructures for Chagas’ control include housing improvement projects (Plan International and Pro‑Habitat) and credit cooperatives (Pro‑Mujer and ProHabitat), discussed in the next chapter.[50]

PBCM’s Chagas’ control programs were based upon the following conclusions derived from baseline studies (see Appendix 14): Many peasants live in unhealthy houses that should be bug‑proofed; peasants often do not know the danger triatomines present in their houses and therefore are in need of health education; peasants need technical assistance in home‑improvement projects and in spraying insecticides. The goal was basically preventativeto break the transmission chain by means of education, house improvement and improved hygiene, and by spraying for insects. Of some consideration, PBCM lacked a therapeutic outreach program for those with Chagas’ disease, even though its primary health care program assisted severe cases of heart disease and colonopathy.

Prevention breaks the transmission cycle of T. cruzi from triatomines to humans. In its most basic form, prevention against Chagas’ disease involves the following objectives: periodically spraying with insecticides to destroy triatomines, improvement of housing and corrals to eliminate nesting areas of triatomines, and better housing hygiene. However, each of these objectives involves achieving many changes within the household which are difficult to accomplish. Because the house is the base for peasants’ economy, where they eat, sleep, give birth, raise children, process food, store crops, and keep animals, Chagas’ control projects have difficulty changing some of these cultural and economic practices. Project personnel often overly concentrate on health issues rather than on issues of productivity and economics.