Cryptosporidium exposure associated with crabbing within urban Baltimore watersheds
Cynthia McOliver, MPH Powerpoint Slides
Angling and other recreational water activities are integral activities for millions of Americans. Urban waters used for such recreational activities that also serve as sources of food supplementation and subsistence are often contaminated by waterborne pathogens such as Cryptosporidium species. However, few studies have specifically explored microbial risks to recreationists (i.e., swimmers, boaters, anglers and crabbers) from recreational water contact despite multiple waterborne illnesses and outbreaks.
Our studies were carried out to assess the prevalence and intensity of recreational water activities in the Baltimore metropolitan area among HIV/AIDS patients, for whom cryptosporidiosis is a serious opportunistic illness. HIV/AIDS patients were surveyed at the Johns Hopkins Moore AIDS Clinic in Baltimore, Maryland, to assess the frequency and intensity of their recreational water contacts. The interviews were conducted based on a convenience sample of 102 HIV/AIDS patients from August to September of 2006. Almost 50 percent of patients reported taking part in recreational water activities, 65 percent of which reported participating in at least one recreational activity that included wild-catch-consumption, i.e., fish or crab. A follow-up survey of 153 patients was conducted in 2007. Patients who engaged in recreational water contacts were more likely to report consumption of wild-catch fish or crabs (61 out of 73, 84 percent) compared to those who did not report recreational water activities (41 out of 80, 51 percnet). Overall consumption of caught fish and crabs was high, as 102 out of 153 patients (67 percent) reported eating these foods.
These findings demonstrate that the surveyed HIV/AIDS population commonly engages in recreational water activities leading to contact with Cryptosporidium-contaminated waters in urban settings of Baltimore. In addition, these results raise concerns regarding the quality of our recreational waters, the microbial safety of seafood obtained in these waters, and the ability of regulatory agencies to address and regulate microbial risks posed to anglers and other recreationists by surface waters in urban settings.
Cynthia McOliver is a 3rd year PhD student in the division of environmental engineering in the Department of Environmental Health Sciences. She has a background in biological sciences and public health. Her current research interests are focused on food and water quality, molecular detection of human enteric parasites, such as Cryptosporidium in environmental samples, and assessment of risks of waterborne diseases from contact with contaminated waterways, specifically via recreational contact.
