S Toxocara Seroprevalence and Associated Risk Factors in the United States


tropical medical, toxocariasis, seroprevalence of toxocariasis


Caused by the parasitic nematodes Toxocara canis and cati, toxocariasis in humans can result in covert toxocariasis, ocular toxocariasis, visceral larval migrans, and neurotoxocariasis. A common infection, toxocariasis exposure varies widely within and between countries, with a previous estimate of Toxocara seroprevalence using data from 1988 to 1994 in the United States of approximately 13%. Age, poverty, sex, educational attainment, ethnicity, and region have been associated with Toxocara seroprevalence. In this study, we sought to determine the seroprevalence of and factors associated with Toxocara seropositivity in the United States using data from the National Health and Nutrition Examination Survey from 2011 to 2014 to provide a more recent estimate of Toxocaraseroprevalence in the United States. We found an overall Toxocara seroprevalence of 5.1%. Increasing age, male sex, low educational attainment, low income, and immigration status each was associated with Toxocaraseropositivity. Mexican Americans had reduced odds of exposure. These findings show that exposure to Toxocaracontinues in the United States and that several demographic factors influence the risk of exposure.

Original Publication Citation

Berrett, Andrew N., Lance D. Erickson, Shawn D. Gale, Allison Stone, Bruce L. Brown, and Dawson W. Hedges. (2017). “Toxocara seroprevalence and associated risk factors in the United States.” American Journal of Tropical Medicine and Hygiene. 97(6):1846-1850. DOI:10.4269/ajtmh.17-0542.

Document Type

Peer-Reviewed Article

Publication Date


Permanent URL



The American Journal of Tropical and Hygiene




Family, Home, and Social Sciences



University Standing at Time of Publication

Associate Professor