Toxoplasma gondii as a parasite in food: analysis and control

Authors: Hill, Dolores; Dubey, Jitender

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 3/31/2016
Publication Date: 8/26/2016
Citation: Hill, D.E., Dubey, J.P. 2016. Toxoplasma gondii as a parasite in food: analysis and control. Book Chapter. 4(4):0011-2015. https://doi.org/10.1128/microbiolspec.PFS-0011-2015.
DOI: https://doi.org/10.1128/microbiolspec.PFS-0011-2015

Interpretive Summary: Outbreaks of disease resulting from foodstuffs contaminated by parasitic protozoa have become increasingly recognized as a problem in the U.S. and globally. Increased international trade in food products has made movement of these organisms across national boundaries more frequent, and the risks associated with infections has become apparent in nations with well developed food safety apparatus in place. Some of the more common protozoal infections are frequently transmitted by food containing fecally contaminated soil or water, which carry the environmentally resistant oocyst stage of the parasites (Cyclospora cayetanensis, Cryptosporidium spp., Giardia lamblia, Toxoplasma gondii, Sarcocystis spp., Entamoeba histolytica). However, both T. gondii and Sarcocystis can also be transmitted by consumption of a cyst stage of the parasite which is present in the meat of infected animals. Differences in the definitive and intermediate hosts exist between these pathogens which impact their abundance and geographical distribution in the environment. Toxoplasmosis, caused by Toxoplasma gondii, is one of the most common parasitic infections of humans and other warmblooded animals. Nearly one third of humans have been exposed to the parasite. Congenital infection occurs when a woman becomes infected during pregnancy and transmits the parasite to the fetus. Humans also become infected by ingesting food or water contaminated with sporulated oocysts from infected cat feces or tissue cysts in undercooked meat. Food animals become infected by the same routes, resulting in meat products containing tissue cysts, which can then infect consumers. Implementation of animal management factors, such as biosecure confinement housing, are important in reducing the levels of infection in animals destined for human consumption.

Technical Abstract: Toxoplasmosis, caused by Toxoplasma gondii, is one of the most common parasitic infections of humans and other warmblooded animals. Nearly one third of humans have been exposed to the parasite. Congenital infection occurs when a woman becomes infected during pregnancy and transmits the parasite to the fetus. Humans also become infected by ingesting food or water contaminated with sporulated oocysts from infected cat feces or tissue cysts in undercooked meat. Food animals become infected by the same routes, resulting in meat products containing tissue cysts, which can then infect consumers. Implementation of animal management factors, such as biosecure confinement housing, are important in reducing the levels of infection in animals destined for human consumption.