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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Animal Parasitic Diseases Laboratory » Research » Publications at this Location » Publication #323794
Title: Quantifying the risk of human Toxoplasma gondii infection due to consumption of domestically-produced lamb in the United States

Author
item GUO, MIAO - University Of Maryland
item MISHRA, ABHINAV - University Of Maryland
item BUCHANAN, ROBERT - University Of Maryland
item Dubey, Jitender
item Hill, Dolores
item GAMBLE, H. RAY - National Academy Of Sciences - United States
item JONES, JEFFREY - Centers For Disease Control And Prevention (CDC) - United States
item PRADHAN, ABANI - University Of Maryland

Submitted to: International Association for Food Protection Proceedings
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/22/2016
Publication Date: 7/1/2016
Citation: Guo, M., Mishra, A., Buchanan, R.L., Dubey, J.P., Hill, D.E., Gamble, H., Jones, J.L., Pradhan, A.K. 2016. Quantifying the risk of human Toxoplasma gondii infection due to consumption of domestically-produced lamb in the United States. International Association for Food Protection Proceedings. 79:1181-1187.

Interpretive Summary: Toxoplasmosis caused by a single celled parasite, Toxoplasma gondii and continues to be a worldwide public health problem. Human toxoplasmosis accounts for an estimated one-fifth of all diagnosed foodborne infections in the United States, and one fifth of the economic costs attributable to any foodborne pathogen. Pregnant women and their fetuses are exposed to elevated health risks. The goal of this study was to develop a farm-to-table quantitative microbial risk assessment model to predict the public health risk associated with consumption of fresh lamb in the United States. In the context of available data, sensitivity analysis suggested that cooking is the most important parameter impacting human health risk. This study provides a scientific basis for risk management and also could serve as a baseline model to quantify infection risk from T. gondii and other parasites associated with meat products. These results will be useful for veterinarians, parasitologists, immunologists, and epidemiologists interested in understanding transmission risks attributable to consumption of undercooked lamb for toxoplasmosis.

Technical Abstract: Toxoplasma gondii is a widely prevalent protozoan parasite worldwide. Human toxoplasmosis is responsible for considerable morbidity and mortality in the United States. Meat products have been identified as an important source of T. gondii infections in humans. The goal of this study was to develop a farm-to-table quantitative microbial risk assessment (QMRA) model to predict the public health burden in the United States associated with consumption of U.S. domestically-produced lamb. Following the baseline model for fresh pork that we developed previously, the present risk model was divided into five modules. T. gondii prevalence in market lambs was pooled from the 2011 National Animal Health monitoring system (NAHMS) survey, and the concentration of the infectious life stage (bradyzoites) was calculated in the current model. Similar to the baseline model, a log-linear regression and an exponential dose-response model was used to model the reduction of T. gondii during home cooking and to predict the probability of infection, respectively. The mean probability of infection per serving of lamb was estimated to be 1.5 cases per 100,000 servings, corresponding to approximately 6,300 new infections per year in the U.S. population. Based on the sensitivity analysis, cooking was identified as the most effective method to influence human health risk. This study provides a QMRA framework for T. gondii infection through consumption of lamb, and quantified the infection risk and public health burden associated with lamb meat consumption.