Congenital Toxoplasmosis and Reinfection during Pregnancy: Case Report, Strain Characterization, Experimental Model of Reinfection, and Review

Abstract

We present a case of disseminated congenital toxoplasmosis in a newborn born to a mother who had been immunized against toxoplasmosis before conception. The mother was reinfected, likely by ingestion of imported raw horse meat during pregnancy. This clinical presentation is exceptional in France and raised the possibility of infection by a highly virulent Toxoplasma strain. The strain responsible was isolated from the peripheral blood of the newborn, and when genotyped with microsatellite markers, it exhibited an atypical genotype, one which is very uncommon in Europe but had been described in South America. We tested the hypothesis of a reinfection with a different genotype by using an experimental mouse model, which confirmed that acquired immunity against European Toxoplasma strains may not protect against reinfection by atypical strains acquired during travel outside Europe or by eating imported meat.

Sero-epidemiology and risk factors for Toxoplasma gondii among pregnant women in Arab and African countries

“…This belief is changing because of greater genetic diversity as a result of sexual recombination of the parasite (Su et al 2010;Khan et al 2011). A recent study indicated that congenital T. gondii can occur in immune mothers (seropositive) when an atypical genotype overcomes the acquired resistance from the original infecting genotype (Elbez-Rubinstein et al 2009). Moreover, a study recently demonstrated a severe form of congenital T. gondii in children of non-immune mothers in the third trimester (Delhaes et al 2010), which is rarely caused by the typical genotypes.…”

Toxoplasma gondii: epidemiology, feline clinical aspects, and prevention

“…Historically, women demonstrating exposure to T. gondii prior to pregnancy through serology were considered safe from future infection and risk to the fetus. However, apparent recrudescent infections during pregnancy can occur in immunocompetent mother although few cases have been reported [10]. A case of maternal T. gondii infection and subsequent fetal infection was reported in a 31-year old French woman with serological evidence of previous T. gondii exposure.…”

Genetic characterisation of Toxoplasma gondii in wildlife from North America revealed widespread and high prevalence of the fourth clonal type

“…Recently, attention has been focused on the genetic variability among T. gondii isolates from apparently healthy and sick hosts (Howe et al, 1997;Grigg and Sundar, 2009). Severe cases of toxoplasmosis have been reported in immunocompetent patients in association with atypical T. gondii genotypes (Ajzenberg et al, 2004;Demar et al, 2007;Elbez-Rubinstein et al, 2009;Grigg and Sundar, 2009;Vaudaux et al, 2010;Wendte et al, 2010).…”