Congenital Toxoplasmosis: A Review

Abstract

Toxoplasmosis is caused by infection with the protozoan parasite Toxoplasma gondii. In the United States, approximately 85% of women of childbearing age are susceptible to acute infection with T. gondii. Acute infections in pregnant women may cause serious health problems when the organism is transmitted to the fetus (congenital toxoplasmosis), including mental retardation, seizures, blindness, and death. An estimated 400 to 4000 cases of congenital toxoplasmosis occur in the U.S. each year. Manifestations of congenital toxoplasmosis may not become apparent until the second or third decade of life. Serologic tests are used to diagnose acute infection in pregnant women, but false-positive tests occur frequently, therefore, serologic diagnosis must be confirmed at a reference laboratory before treatment with potentially toxic drugs should be considered. Much of congenital toxoplasmosis can be prevented by educating women of childbearing age and pregnant women to avoid eating raw or undercooked meat, to avoid cross-contamination of other foods with raw or undercooked meat, and to use proper cat-litter and soil-related hygiene.

Prevalence of acute toxoplasmosis infection among 41,112 pregnant women and the mother-to-child transmission rate in a public hospital in South Brazil

“…In Brazil, the Southern region, where this study was conducted, has a low prevalence of toxoplasmosis among pregnant women (Nobrega & Karnikowski 2005, Figueiro-Filho et al 2007. However, there is substantial variability in the reported data, depending on chosen population, diagnostic methods used in screening, or even the different risk factors involved in disease transmission (Buffolano et al 1996, Kapperud et al 1996, Cook et al 2000, Jones et al 2001.…”

“…Mother-to-child transmission (MTCT) rates have been found to be around 20-50% (Jones et al 2001). Several studies have suggested lower rates of foetal transmission when maternal infection took place early during gestation (Hohlfeld et al 1989, Jenum et al 1998, Dunn et al 1999, Remington et al 2005.…”

Temporal Association Between Land-Based Runoff Events and California Sea Otter (Enhydra Lutris Nereis) Protozoal Mortalities

“…In addition to causing mortality in sea otters, T. gondii is a zoonotic pathogen that infects up to one third of the human population (Hill and Dubey, 2002). Although infection is most often asymptomatic, death due to disseminated disease can occur in immunocompromised humans, and acute infection during pregnancy can result in abortion or congenital disease in the fetus (Jones et al, 2003). Sarcocystis neurona is not known to infect humans but is one of the main causes of equine protozoal myeloencephalitis (EPM), resulting in substantial morbidity and mortality of affected animals (Fenger, 1997).…”

Risk factors for Toxoplasma gondii infection among pregnant women from the State of Tocantins, Northern Brazil

“…The transmission of T. gondii to the fetus might result in mental retardation, seizures, blindness, hydrocephalus, cerebral calcifi cation, chorioretinitis, and ultimately death (4) . However, in some cases the health problems remain unapparent until the second or third decade of life (5) .…”