Screening of Pregnant Women for Anti-Toxoplasma Antibodies and their Newborn for Vertical Transmission
Dr. Subba Rama Prasad,
Professor, Department of Microbiology, Sri Devaraj URS Medical College, Tamaka,
Introduction: Toxoplasmosis is a world-wide protozoan-zoonosis caused by Toxoplasma gondii (T. gondii). Primary infections during pregnancy may result in miscarriages, still births, and congenital malformations in the new born. Studies on vertical transmission of toxoplasmosis from India are lacking.
Aim: To estimate the seroprevalence of antibodies to T. gondii among pregnant women from the rural population of Kolar and to document vertical transmissions, if any.
Materials and Methods: Anti-Toxoplasma IgG levels were estimated among 251 women admitted for labour at a tertiary care hospital in Kolar, Karnataka, between December 2014 and October 2016, by enzyme linked immunosorbent assay (ELISA). Demographic, socio-economic, and obstetrical data along with exposure to risk factors among the participants were recorded. Two hundred and fifty one cord blood samples of the newborns of the above mothers were tested for anti-Toxoplasma IgM antibodies by Âµ capture ELISA. The validity of an IgM positive reaction was evaluated. The differences in proportions were analysed by the Chi-square test and the differences in means were analysed by the unpaired t-test. A p-value of <0.05 was considered significant.
Results: IgG antibodies to T. gondii could be detected in 53 (21.1%) of the mothers tested; the titres ranged between 35 IU/ml â€“ 350 IU/ml. Mothers from lower socio-economic strata had significantly higher prevalence as compared to mothers from middle classes. The seropositivity was not significantly associated with gravid status, literacy, occupation, exposure to cats, consumption of raw meat, salad, or drinking untreated water, gestational age, previous history of abortion or the mode of delivery. Cord blood samples from 5 (2 %) of the newborns gave positive IgM reactions, but they were interpreted as false positives as there was no evidence of infection in their respective mothers or the baby lacked antibodies on follow up.
Conclusions: About one fifth of the pregnant women in Kolar region, possess anti-Toxoplasma IgG antibodies and are immune to toxoplasmosis. The rest, constituting a large proportion, are susceptible and run the risk of infection during pregnancy. Routine screening of women for Toxoplasma infections during pregnancy and screening of newborns for congenital toxoplasmosis are recommended.