Trypanosoma cruzi infection in the opossum Didelphis marsupialis: absence of neonatal transmission and protection by maternal antibodies in experimental infections

Abstract

The high rate of natural Trypanosoma cruzi infection found in opossums does not always correlate with appreciable densities of local triatomid populations. One alternative method which might bypass the invertebrate vector is direct transmission from mother to offspring. This possibility was investigated in five T. cruzi infected females and their litters (24 young). The influence of maternal antibodies transferred via lactation, on the course of experimental infection, was also examined. Our results show that neonatal transmission is probably not responsible for the high rate of natural T. cruzi infection among opossums. In addition antibodies of maternal origin confer a partial protection to the young. This was demonstrated by the finding of a double prepatency period and 4, 5 fold lower levels of circulating parasites, in experimentally infected pouch young from infected as compared to control uninfected mothers. On the other hand, the duration of patent parasitemia was twice as long as that observed in the control group.

Long-term reduction of Trypanosoma cruzi infection in sylvatic mammals following deforestation and sustained vector surveillance in northwestern Argentina

“…Vertical transmission (including infections acquired congenitally and during lactation) and horizontal transmission (through urine or anal gland secretions) appear to be very unlikely routes of infection in Didelphis sp. (Jansen et al, 1994;Grisard et al, 2000;Telford and Tonn, 1982;Travi et al, 1994). The observed ageprevalence curves in opossums, increasing with time of exposure (age) after weaning, are consistent with vector-mediated transmission.…”

Trypanosoma cruzi infection in Leontopithecus rosalia at the Reserva Biológica de Poço das Antas, Rio de Janeiro, Brazil

“…Each number signifies one isolate for each golden lion tamarin especimen. Lanes 1 to 9 correspond to isolates of animals 583, 291, 310, 385, 493, 584, 593, 633 and 592. of T. cruzi is rare among humans and other mammalian orders including Marsupialia (Jansen et al 1994). Infection of free-ranging tamarins with T. cruzi probably occurs by contamination with the feces of infected triatomine bugs, since these primates do not include hemipterans in their diet Fig.…”

Humoral Immune Response Kinetics in Philander opossum and Didelphis marsupialis Infected and Immunized by Trypanosoma cruzi Employing an Immunofluorescence Antibody Test

“…Our data indicate that maternal antibodies transferred during lactation could probably confer protection to young P. opossum in the pouch, since newly weaned animals control this parasitism in experimental infections as do naturally infected young animals. It has been reported that marsupials acquire antibodies only a few hours after suckling for the first time (Hindes & Mizell 1976), and that D. marsupialis maternal antibodies confer partial protection to the young (Jansen et al 1994).…”