Date: Sat, 1 Jun 1996 15:26:48 -0400 From: "Flynn Mclean" Subject: MMWR 05/31/96 MORBIDITY AND MORTALITY WEEKLY REPORT ****************************************** Centers for Disease Control and Prevention May 31, 1996 Vol. 45, No. 21 Outbreak of Cryptosporidiosis at a Day Camp -- Florida, July-August 1995 On July 27, 1995, the Alachua County Public Health Unit (ACPHU) in central Florida was notified of an outbreak of gastroenteritis among children and counselors at a day camp on the grounds of a public elementary school. This report summarizes the outbreak investigation, which implicated Cryptosporidium parvum as the causative agent and underscores the role of contaminated water as a vehicle for transmission of this organism. The camp operated from June 12 through August 4 and enrolled 98 children (age range: 4-12 years) and six counselors during the 3 weeks before the outbreak. A confirmed case of cryptosporidiosis was defined as gastrointestinal symptoms (i.e., abdominal pain, nausea, vomiting, and three or more watery stools each day) in a camp attendee during July 20-August 23 with C. parvum isolated in stool. A probable case was defined as gastrointestinal symptoms during July 20-August 23 in a camp attendee who did not submit a stool sample for testing. A questionnaire was administered to each of the 104 persons attending the camp; for some children, information was obtained from parents and camp records. Of the 104 persons attending the camp, 77 (74%) had symptoms (abdominal pain [74%], nausea [73%], diarrhea [71%], vomiting [57%], and fever [43%]) with onset during July 20-August 15, including 72 of 98 children and five of six counselors (Figure 1). Follow-up phone calls to 67 of 79 households of those who attended the camp indicated that 24 household members had onset of gastrointestinal symptoms during July 20-August 23. Stool specimens for bacterial enteric pathogen testing were obtained from 44 camp attendees within 10 days of onset of symptoms; all were negative. Sixteen stool specimens were obtained for testing for ova and parasites; all 16 yielded C. parvum. Risk for illness was not associated with participating in a particular camp activity or eating a lunch or snack provided by the camp. Water sources for the camp included an outdoor drinking fountain, a sink inside the trailer that served as camp headquarters, and portable coolers. The coolers were filled at either a kitchen sink inside the school or an outdoor faucet with an attached hose and spray nozzle used for washing garbage cans. Although water consumption from any source could not be quantified, virtually all persons at the camp reported drinking water from one of the camp sources during the 3 weeks before the outbreak. Water samples were tested (1) from the city's water treatment plant, all school sources used by campers, and three sinks inside the school. The water treatment plant samples were repeatedly negative. Outdoor faucet samples were positive for total coliforms and C. parvum; other tests from school sites were negative or below detectable limits for total coliform, Escherichia coli, and ova and parasites. The area around the outdoor faucet was not fenced, and feces of unknown origin were observed on several occasions near the faucet and attached hose. Based on these findings, ACPHU recommended discontinuing use of coolers for water and the outdoor faucet, and enclosing the faucet area by fence. In addition, parents and staff were taught proper handwashing technique and given information about C. parvum. Staff returning to school used alternate water sources until the system was superchlorinated, flushed, and cleared. Reported by: J Regan, R McVay, M McEvoy, J Gilbert, Water and Wastewater Systems, Gainesville Regional Utilities. R Hughes, T Tougaw, E Parker, PhD, W Crawford, J Johnson, School Board of Alachua County, Gainesville, Florida. J Rose, PhD, Univ of South Florida, St. Petersburg, Florida. S Boutros, PhD, Environmental Associates Ltd, Bradford, Pennsylvania. S Roush, MPH, T Belcuore, MS, C Rains, MD, J Munden, MPH, Alachua County Public Health Unit; L Stark, PhD, E Hartwig, ScD, M Pawlowicz, Florida Dept of Health and Rehabilitative Svcs State Laboratory; R Hammond, PhD, D Windham, R Hopkins, MD, State Epidemiologist, Florida Dept of Health and Rehabilitative Svcs. Div of Field Epidemiology, Epidemiology Program Office, CDC. Editorial Note: The protozoan parasite C. parvum was first identified as a human pathogen in 1976; since then, the organism has been increasingly recognized as an agent of gastrointestinal illness. In immunocompetent persons, cryptosporidiosis can cause moderately severe watery diarrhea that usually lasts 1-20 days (average: 10 days) (2). In immunocompromised persons (e.g., those with acquired immunodeficiency syndrome [AIDS] or those taking certain chemotherapeutic regimens), the infection can cause severe, unrelenting diarrhea. The antibiotic paromomycin can improve symptoms and decrease parasite excretion in the feces of some persons with AIDS and is the treatment of choice for immunosupppressed patients (3,4). Cryptosporidiosis is transmitted by the fecal-oral route, most commonly by direct person-to-person transmission or by drinking water that has been contaminated with human or animal feces. In 1993, cryptosporidiosis caused the largest waterborne disease outbreak ever recorded, when an estimated 400,000 persons in Milwaukee became ill after drinking contaminated municipal water (5). The outbreak described in this report most likely was related to drinking contaminated water. Contamination probably occurred at the nozzle of the hose used to fill the water coolers rather than at or near the water treatment plant. Sources of drinking water should be protected from possible fecal contamination, and hoses, which are particularly susceptible to back-syphonage, should not be used to provide drinking water. Public water sources that cannot be protected should be posted as nonpotable. C. parvum was promptly identified as the source of this outbreak, in part because the Florida State Public Health Laboratory examines all fecal specimens submitted for ova and parasite analysis for C. parvum. The diagnosis of cryptosporidiosis can be delayed or missed when physicians assume incorrectly that diagnostic laboratories routinely perform specific tests for C. parvum when a fecal examination for parasites is requested. A recent national survey of clinical laboratories found that only 5% did so (6). If cryptosporidiosis is suspected in the differential diagnosis, physicians should specifically request testing for C. parvum. In addition, when reporting the results of fecal examinations, clinical laboratories should specify what tests were performed rather than only indicating that no enteric pathogens were identified. References 1. Messer JW, Fout GS, Schafer FW, Dahling DR, Stetler RE. Information Collection Rule (ICR): Microbiology Laboratory Manual [Draft]. Cincinnati, Ohio: US Environmental Protection Agency, February 1995. 2. American Academy of Pediatrics. Cryptosporidiosis. In: Peter G, ed. 1994 Red book: report of the Committe on Infectious Diseases. 23rd ed. Elk Grove Village, Illinois: American Academy of Pediatrics;1994:171-2. 3. White AC Jr, Chappell CL, Hayat CS, Kimball KT, Flanigan TP, Goodgame RW. Paromomycin for cryptosporidiosis in AIDS: a prospective, double-blind trial. J Infect Dis 1994;170:419-24. 4. Anonymous. Drugs for parasitic infections. Med Lett Drugs Ther 1995;37:99-108. 5. Mac Kenzie WR, Hoxie NJ, Proctor ME, et al. A massive outbreak in Milwaukee of Cryptosporidium infection transmitted through the public water supply. N Engl J Med 1994;331:161-7. 6. Boyce TG, Pemberton AG, Addiss DG. Cryptosporidium testing practices among clinical laboratories in the United States. Ped Infect Dis J 1996;15:87-8. Notice to Readers Satellite Videoconference on Essentials of Managed Care and the Implications for Public Health Officials CDC, the Health Resources and Services Administration, the Association of State and Territorial Health Officials, the National Association of County and City Health Officials, the Public Health Foundation, and the Public Health Training Network (PHTN) will cosponsor a satellite videoconference, "Essentials of Managed Care and the Implications for Public Health Officials," on June 28, 1996, from 11:30 a.m. to 4 p.m. eastern daylight time. This videoconference will present principles and business practices of managed care, followed by a discussion of public health challenges and opportunities in a managed-care environment. The course consists of didactic segments, group activities, and opportunities for questions and answers. Information about enrollment is available by calling (800) 468-4456. There is an enrollment fee. Materials will be delivered to participants before the broadcast. Information about viewing sites is available from PHTN, telephone (800) 728-8232; from the PHTN/CDC Fax Information System, (404) 332-4565 (request document 564012); and from state PHTN distance-learning coordinators. Notice to Readers National Occupational Research Agenda Each day in the United States, an average of 137 persons die from work-related diseases (1); an additional 16 die from on-the-job injuries (2). In 1994, employers reported 6.3 million work-related injuries and 515,000 cases of occupational illnesses (3). In the same year, occupational injuries alone cost $121 billion in lost wages, lost productivity, administrative expenses, health care, and related costs (4)--a figure that does not include the costs of occupational diseases, for which reliable estimates are not available. As jobs shift from manufacturing to services, increasingly common characteristics include longer hours, compressed workweeks, shift work, part-time and temporary work, and diminished job security; in addition, new chemicals, materials, processes, and equipment are being introduced more quickly. In response to these issues and to provide a framework to guide occupational safety and health research during the next decade, CDC's National Institute for Occupational Safety and Health (NIOSH) and its partners in the public and private sectors have published the National Occupational Research Agenda (NORA) (5).* Approximately 500 outside organizations and persons provided input to NIOSH for the development of NORA. This effort to focus and coordinate research--both for NIOSH and the entire occupational safety and health community--attempts to address systematically topics identified as high priority and most likely to yield health and safety improvements for workers and industry. NORA identifies 21 research priorities grouped into three categories: Disease and Injury, Work Environment and Workforce, and Research Tools and Approaches (see box). To initiate implementation of NORA, NIOSH will convene its NORA partners to refine further the preliminary approaches agreed to in identifying the NORA research priorities. Throughout the process of implementing NORA, NIOSH will attempt to expand its partnerships and improve coordination throughout the occupational safety and health community. References 1. Landrigan PJ, Baker DB. The recognition and control of occupational disease. JAMA 1991;266:676-80. 2. Jenkins EL, Kisner SM, Fosbroke DE, et al. Fatal injuries to workers in the United States, 1980-89: a decade of surveillances; national profile. Cincinnati: US Department of Health and Human Services, Public Health Service, CDC, 1993; DHHS publication no. (NIOSH)93-108. 3. Bureau of Labor Statistics. Workplace injuries and illnesses in 1994. BLS News, December 15, 1995; publication 95-508. 4. National Safety Council. Accident facts. Itasca, Illinois: National Safety Council, 1995. 5. NIOSH. National Occupational Research Agenda. Cincinnati: US Department of Health and Human Services, Public Health Service, CDC, 1996; DHHS publication no. (NIOSH)96-115. * Single copies of NORA are available without charge from the Publications Office, NIOSH, CDC, Mailstop C-13, 4676 Columbia Parkway, Cincinnati, OH 45226-1998; telephone (800) 365-4674 or (for persons outside the United States) (513) 533-8328; fax (513) 533-8573. NORA also is available on the NIOSH Home Page on the World-Wide Web: http://www.cdc.gov/ niosh/homepage.html. Priority Research Areas for National Occupational Research Agenda Category Research Priority Disease and Injury Allergic and irritant dermatitis Asthma and chronic obstructive pulmonary disease Fertility and pregnancy abnormalities Hearing loss Infectious diseases Low-back disorders Musculoskeletal disorders of the upper extremities Traumatic injuries Work Environment and Workforce Emerging technologies Indoor environment Mixed exposures Organization of work Special populations at risk Research Tools and Approaches Cancer research methods Control technology and personal protective equipment Exposure assessment methods Health services research Intervention effectiveness research Risk assessment methods Social and economic consequences of workplace illness and injury Surveillance research methods