Congenital Chagas' disease in Bolivia: epidemiological aspects and pathological findings

Abstract

In 329 newborns examined by the method of Strout and/or histopathological sections of the placenta, Trypanosoma cruzi was observed in 25 cases. The serological prevalence of Chagas' disease in mothers was 51%. A greater risk of congenital transmission was observed in newborns ranging between 1,001 and 2,500 g (21%), compared to 2% in newborns weighing more than 2,500 g. Congenital transmission occurred predominantly in newborns with a gestational age of 26 to 37 weeks. Histopathological examination of placentae disclosed T. cruzi in 6.3%. In areas with a high prevalence of Chagas' disease, congenital transmission is a real hazard.

A 9,000-year record of Chagas' disease

“…Congenital transmission occurs in 0.5-6.3% of infants born to Chagas'-infected mothers (11,35). There is no reason to expect these rates to have been less in antiquity.…”

Integrate Study of a Bolivian Population Infected by Trypanosoma cruzi, the Agent of Chagas Disease

“…The vectorial transmission of Trypanosoma cruzi, the agent of the disease, is mainly assured by Triatoma infestans which presents a T. cruzi infection rate of around 30% (WHO 1991). The vector control program is not yet expanded over all the country and, due to the large chagasic population, congenital transmission and transmission by blood transfusion are very abundant too (Azogue et al 1985, Azogue & Darras 1995. High seroprevalences reported in blood donors indicate the magnitude of the human infection even in the towns outside the endemic regions (Carrasco et al 1990, Landivar et al 1992.…”

Congenital Chagas Disease: Estimating the Potential Risk in the United States

“…45,46 Because most immigrants in the United States are from Mexico and Central America, it may be possible that the T. cruzi I lineage infecting them is less able to produce congenital T. cruzi infection than the T. cruzi II lineage, which is more common in countries from the Southern cone, where most cases of congenital T. cruzi infection have been described. 1,3,4,[7][8][9][10][11][12][13][14][15][16][17][18][19][20] In addition, because neither the Hispanic pregnant women nor their newborns are screened for Chagas disease, it may also be possible that inexperienced health personnel miss the asymptomatic or oligosymptomatic cases and the symptomatic cases. The experience in Latin America shows that, when cases are being looked for, they are readily found.…”

“…1 Congenital Chagas disease has been reported from Argentina, Bolivia, Brazil, Chile, Colombia, Guatemala, Honduras, Paraguay, Uruguay, and Venezuela, 2 as well as from Mexico 5 and Peru. 6 The rate of congenital T. cruzi transmission varied from 0.75% to 7.1% in Argentina 1,[7][8][9][10][11] ; from 4% to 9.5% in Bolivia 1,8,[12][13][14] ; from 1% to 10.5% in Brazil 1,2,15-17 ; from 0.49% to 19% in Chile 1,8,18 ; from 1.44% to 10% in Paraguay 8,19,20 ; and from 0.13% to 1.57% in Uruguay. 1 Several factors such as parasitemia in the mother, parasite strain, techniques used for diagnosis (microhematocrit, polymerase chain reaction [PCR], histopathology, and/or serology) as well as methodologic aspects (target population [underweight newborns] or the time after delivery in which the sample for testing is obtained), may contribute to these variations on rates of congenital T. cruzi transmission.…”