A survey of congenital Chagas’ disease, carried out at three Health Institutions in São Paulo City, Brazil

Abstract

The congenital transmission of Chagas’ disease was evaluated in 57 pregnant women with Chagas’ disease and their 58 offspring. The patients were selected from three Health Institutions in São Paulo City. The maternal clinical forms of Chagas’ disease were: indeterminate (47.4%), cardiac (43.8%) and digestive (8.8%); 55 were born in endemic areas and two in São Paulo City. The transmission of Chagas’ disease at fetal level was confirmed in three (5.17%) of the 58 cases studied and one probably case of congenital Chagas’ disease. Two infected infants were born to chagasic women with HIV infection and were diagnosed by parasitolological assays (microhematocrit, quantitative buffy coat-QBC or artificial xenodiagnosis). In both cases the placenta revealed T. cruzi and HIV p24 antigens detected by immunohistochemistry. In one case, a 14-week old abortus, the diagnosis of congenital T. cruzi infection was confirmed by immunohistochemistry. The other probable infection, a 30-week old stillborn, the parasites were found in the placenta and umbilical cord. The Western blot method using trypomastigote excreted/secreted antigens of T. cruzi (TESA) was positive for IgG antibodies in 54/55 newborns and for IgM in 1/55 newborns. One of the two newborns with circulating parasites had no detectable IgG or IgM antibodies. The assessment of IgG antibodies in the sera of pregnant women and their newborns was performed by ELISA using two different T. cruzi antigens: an alkaline extract of epimastigotes (EAE) and trypomastigote excreted/secreted antigens (TESA). The analysis showed a linear correlation between maternal and newborn IgG antibody titers at birth.

Risk Factors Associated with Triatomines and Its Infection with Trypanosoma cruzi in Rural Communities from the Southern Region of the State of Mexico, Mexico

“…cruzi can be found in the triatomine's feces and is transmitted when vector feces containing metacyclic trypomastigotes is inoculated into the insect's bite site through scratching, skin abrasions, or even through some mucous membranes. 2 It can also be transmitted by blood transfusion 3,4 and congenital infection 5,6 or the ingestion of infected food. 7 In Mexico, 28 species of hematophagous triatomines have been reported, from which 23 are endemic in some specific regions and the remaining 4 are distributed throughout most of the Chagas-endemic regions of the country.…”

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.…”

Chagas disease prevalence in pregnant women: migration and risk of congenital transmission

“…In addition, it should be noted that at this stage, treatment could lead to complete cure. Diagnosis during pregnancy and risk characterization of a given population should be seen as a window of opportunity for inquest cases of congenital Chagas 4, 7,8]. The healing of congenital Chagas disease in this critical age depends on detection during pregnancy, early diagnosis in the neonate, and quick treatment [5,9].…”

“…In view of this, we decided to survey pregnant women by origin to assess the evolution of the prevalence to find out which populations are at risk of congenital transmission. Although there are some isolated studies related to migration and prevalence [7,[9][10][11][12][13][14], they have not assessed the impact of a specific population over the total prevalence among pregnancies during sufficiently long periods to allow for an evolutionary analysis.…”