Investigating Potential Human Risk and Potential Preventive Measures of Exposure to Baylisascaris procyonis in Texas

EPA Grant Number: U916239
Title: Investigating Potential Human Risk and Potential Preventive Measures of Exposure to Baylisascaris procyonis in Texas
Investigators: Kresta, Amy E.
Institution: Texas A & M University - Kingsville
EPA Project Officer: Packard, Benjamin H
Project Period: January 1, 2003 through January 1, 2006
Project Amount: $88,140
RFA: Minority Academic Institutions (MAI) Fellowships for Graduate Environmental Study (2003) RFA Text |  Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Academic Fellowships , Fellowship - Environmental Science


Baylisascaris procyonis is a parasitic roundworm found in the small intestine of raccoons. This nematode is a zoonotic parasite (can be transmitted from wildlife to humans). Humans can become infected with B. procyonis by ingesting eggs. Female worms can produce more than 1,000,000 eggs/day, which are shed in the feces of infected raccoons. Eggs of B. procyonis are resilient and can survive for years in the environment; thus, increasing the likelihood of transmission to humans. Ingestion may result from contact with contaminated vegetation, soil, water, or raccoon feces. Larvae of B. procyonis in humans can cause liver disease, blindness, seizures, paralysis, and death. The objectives of this research project are to: (1) determine the prevalence of adult B. procyonis in raccoons from Texas; (2) develop a simulation model to examine parasite and raccoon population dynamics to predict the regions within Texas that are most at risk of zoonotic transmission of B. procyonis; (3) investigate techniques that wildlife services personnel and trappers can use to treat their traps to destroy any infective eggs to avoid human exposure; and (4) increase awareness and knowledge of B. procyonis in Texas among not only wildlife researchers and wildlife services personnel, but also among physicians and the general public.

Wildlife researchers and trappers need information about risks dealing with infected raccoons and about how to prevent traps from being contaminated by eggs for prolonged periods of time. The general public needs to be aware of the risks of coming into contact with raccoons and raccoon feces so that these situations may be avoided to reduce potential human exposure to B. procyonis. Physicians need to be aware that B. procyonis is present in Texas, and should be recognized as an important cause of larval migrans in humans. Disseminating information gained from this research project will be of highest priority once the research is complete.


Raccoons will be obtained from selected sites throughout Texas. Relationships among infected raccoons, soil type, vegetative community, precipitation, temperature, and proximity to roads and human population densities will be analyzed. A simulation model also will be developed to analyze which areas of Texas are most at risk for human exposures to B. procyonis by incorporating information about raccoon population dynamics, parasite population dynamics, environmental conditions that prolong egg viability, and proximity of B. procyonis to human population densities. Treatment techniques designed to destroy B. procyonis eggs will be compared. In the laboratory, larvated eggs harvested from adult B. procyonis will be exposed to various cleaning and disinfecting solutions to investigate which treatments are most effective at destroying the eggs. Solutions must be environmentally safe, easily accessible, and safe to use on galvanized steel traps. We expect the results of this research project to indicate which areas of Texas currently have raccoons infected with B. procyonis, which areas of Texas have a higher potential to harbor B. procyonis eggs for long periods of time, and which areas of Texas are at higher risk of human exposure to B. procyonis based on habitat characteristics and proximity of B. procyonis to urban/suburban areas. Results also will identify techniques that wildlife services personnel, wildlife rehabilitators, animal trappers, and wildlife researchers can use to prevent exposure to B. procyonis eggs.

Supplemental Keywords:

fellowship, Baylisascaris procyonis, exposure, parasite, raccoon population, human exposure, habitat characteristics, raccoon feces, roundworm, Texas, TX., Health, Scientific Discipline, PHYSICAL ASPECTS, Geographic Area, Health Risk Assessment, State, Risk Assessments, Physical Processes, disease potential, exposure, contaminated vegetation, Texas (TX), human exposure, Baylisascaris procyonis, parasitic roundworm, human health risk

Progress and Final Reports:

  • 2003
  • 2004
  • Final