Achievements and Challenges upon the Implementation of a Program for National Control of Congenital Chagas in Bolivia: Results 2004–2009

Abstract

Bolivia is one of the most endemic countries for Chagas disease. Data of 2005 shows that incidence is around 1.09‰ inhabitants and seroprevalence in children under 15 ranged from 10% in urban areas to 40% in rural areas. In this article, we report results obtained during the implementation of the congenital Chagas program, one of the biggest casuistry in congenital Chagas disease, led by National Program of Chagas and Belgian cooperation from 2004 to 2009. The program strategy was based on serological results during pregnancy and on the follow up of children born from positive mothers until one year old; if positive, treatment was done with Benznidazole, 10 mg/Kg/day/30 days with one post treatment control 6 months later. Throughout the length of the program, a total of 318,479 pregnant women were screened and 23.31% were detected positive. 42,538 children born from positive mothers were analyzed at birth by micromethod, of which 1.43% read positive. 10,120 children returned for their second micromethod control of which 2.29% read positive, 7,650 children returned for the serological control, of which 3.32% turned out positive. From the 1,093 positive children, 70% completed the 30 day-treatment and 122 returned for post treatment control with 96% showing a negative result. It has been seen that maternal-fetal transmission rates vary between 2% and 4%, with an average of 2.6% (about half of previously reported studies that reached 5%). In this work, we show that it is possible to implement, with limited resources, a National Congenital Chagas Program and to integrate it into the Bolivian health system. Keys of success are population awareness, health personnel motivation, and political commitment at all levels.

Toward Improving Early Diagnosis of Congenital Chagas Disease in an Endemic Setting

“…Accurate early detection and treatment of congenital T. cruzi infection are crucial to this effort. Treatment in infancy results in high cure rates and few side effects, but based on the low sensitivity of the micromethod and poor follow-up rates, more than half of infected infants go unrecognized in current programs [8,10,11]. Even in our study, with dedicated study nurses conducting active searches, 6 infected infants whose conventional testing was negative were lost to follow-up and never treated.…”

“…Conventional serological diagnosis has the major disadvantage of delay: early treatment is preferable and programmatic loss to follow-up at 9 months reaches 80% [10,11]. Negative results at 6 months allow shortened follow-up for some infants, but most are likely to need a specimen at 9 months to effectively rule out infection [8].…”

“…For infants not diagnosed early, one or more specimens must be tested by IgG serology after 6-9 months, once maternal antibodies have cleared [3]. The micromethod, even when optimally executed, fails to detect more than half of infections [8,9], and in control programs, fewer than 20% of infants complete the 9 months of follow-up needed for unequivocal diagnosis [10,11].…”

What is needed for taking emergency obstetric and neonatal programmes to scale?

“…Leadership amongst local policy makers provides the impetus for involving government partners [3]. Leaders initiate planning for the needs of the local health system and facilitate the dialogue between healthcare and public policy providers [49,50].…”

Mother-to-Child Transmission of Trypanosoma cruzi

“…Seropositive mothers are screened during prenatal care or delivery and their offspring are diagnosed and treated. The critical elements for a successful congenital T cruzi prevention program include political commitment, health personnel motivation, and population awareness [23].…”