Volume 97, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



Caused by the parasitic nematodes and , 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 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 seroprevalence. In this study, we sought to determine the seroprevalence of and factors associated with 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 seroprevalence in the United States. We found an overall seroprevalence of 5.1%. Increasing age, male sex, low educational attainment, low income, and immigration status each was associated with seropositivity. Mexican Americans had reduced odds of exposure. These findings show that exposure to continues in the United States and that several demographic factors influence the risk of exposure.


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  • Received : 07 Jul 2017
  • Accepted : 12 Aug 2017
  • Published online : 25 Sep 2017

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