Urban and Community Fisheries Programs: Development, Management, and Evaluation

Assessing the Risks of Exposure to Cryptosporidium from Recreational Water Activities in Baltimore, Maryland

Cynthia C. McOliver, Thaddeus K. Graczyk, and Ellen K. Silbergeld

doi: https://doi.org/10.47886/9781934874042.ch13

Abstract.—Angling and other recreational water activities are integral activities for millions of Americans. Each year over 80 million Americans aged 16 years or older enjoy some recreational activity related to fish and wildlife. Urban waters used for such recreational activities and as sources of food supplementation and subsistence are often contaminated by pathogenic organisms such as Cryptosporidium species, yet few studies have specifically explored microbial risks to recreationists (swimmers, boaters, anglers, and crabbers) from recreational water contact, despite occurrences of waterborne illnesses and outbreaks. Our first study of risks from recreational water contact in Baltimore, Maryland demonstrated that (1) fishing can be a vector of exposure to Cryptosporidium for Baltimore anglers, and (2) there are high levels of recreational water contact, and consumption of fish and crab within this population. Based on these results, a second study was carried out to assess the prevalence of recreational water activities in Baltimore waters in a sub-population of HIV/AIDS patients, for whom cryptosporidiosis is a major opportunistic illness. Patients were surveyed at the Johns Hopkins Moore AIDS Clinic in Baltimore, Maryland. Oral interviews were conducted based on a convenience sample of 102 HIV/AIDS patients, from August–September 2006. Almost 50% of patients reported taking part in recreational water activities, of which 65% reported participating in at least one recreational activity, including fish or crab consumption. These were surprising findings, and in addition to our first study, indicate that recreationists, specifically persons with HIV/AIDS, are engaging in recreational water activities that may lead to contact with pathogen-contaminated waters in urban settings. These findings raise concerns regarding the role of urban fisheries, outdoor recreational water programs, and regulatory agencies in addressing microbial risks posed to anglers and other recreationists in urban settings.