From root@aspensys.com Wed Jun 21 08:38:34 1995 Date: Wed, 21 Jun 1995 11:52:29 +0500 MORBIDITY AND MORTALITY WEEKLY REPORTS Part 1 of 5 ****************************************** Centers for Disease Control and Prevention June 16, 1995 Vol. 44, No. RR-6 Recommendations and Reports U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Public Health Service Centers for Disease Control and Prevention (CDC) Atlanta, Georgia 30333 Assessing the Public Health Threat Associated with Waterborne Cryptosporidiosis: Report of a Workshop The MMWR series of publications is published by the Epidemiology Program Office, Centers for Disease Control and Prevention (CDC), Public Health Service, U.S. Department of Health and Human Services, Atlanta, GA 30333. Centers for Disease Control and Prevention................ David Satcher, M.D., Ph.D. Director The material in this report was prepared for publication by: National Center for Infectious Diseases.... James M. Hughes, M.D. Director Division of Parasitic Diseases........... Daniel G. Colley, Ph.D. Director The production of this report as an MMWR serial publication was coordinated in: Epidemiology Program Office...... Stephen B. Thacker, M.D., M.Sc. Director Richard A. Goodman, M.D., M.P.H. Editor, MMWR Series Scientific Information and Communications Program Recommendations and Reports............ Suzanne M. Hewitt, M.P.A. Managing Editor Lanette B. Wolcott Project Editor Nadine W. Martin Rachel J. Wilson Writer-Editors Morie M. Higgins Visual Information Specialist SUGGESTED CITATION Centers for Disease Control and Prevention. Assessing the public health threat associated with waterborne cryptosporidiosis: report of a workshop. MMWR 1995;44(No. RR-6):[inclusive page numbers]. Copies can be purchased from Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402-9325. Telephone: (202) 783-3238. Use of trade names and commercial sources is for identification only and does not imply endorsement by the Public Health Service or the U.S. Department of Health and Human Services. Contents Introduction................................................1 Background..................................................2 Workshop Objectives.........................................3 Work Group I. Surveillance Systems and Epidemiologic Study Designs............................. 4 Work Group II. Public Health Responses.................. 9 Work Group III: Cryptosporidiosis in Immunocompromised Persons.............................. 10 Work Group IV: Water Sampling Methods and Interpretation of Results ............................. 13 Work Group Conclusions.................................... 14 Surveillance Systems and Epidemiologic Study Designs... 15 Public Health Responses ............................... 15 Cryptosporidiosis in Immunocompromised Persons ........ 15 Water Sampling Methods and Interpretation of Results .. 15 Afterword ................................................ 15 Participating Agencies and Organizations: American Public Health Association American Society for Microbiology American Society of Tropical Medicine and Hygiene American Water Works Association American Water Works Association Research Foundation Association of Independent Scientific, Engineering, and Testing Firms Association of Metropolitan Water Agencies Association of State and Territorial Health Officials Association of State and Territorial Public Health Laboratory Directors Association of State Drinking Water Administrators City of Milwaukee Health Department Council of State and Territorial Epidemiologists Environmental Protection Agency Food and Drug Administration Infectious Diseases Society of America National Alliance of State and Territorial AIDS Directors National Association of County Health Officials National Association of Persons with AIDS National Association of State Public Health Veterinarians National Center for Infectious Diseases, Centers for Disease Control and Prevention National Institute of Allergy and Infectious Diseases, National Institutes of Health National Minority AIDS Council Natural Resources Defense Council U.S. Conference of Local Health Officers U.S. Conference of Mayors U.S. Department of Agriculture Representatives from 40 states The following CDC staff members prepared this report: David G. Addiss, M.D., M.P.H. Michael J. Arrowood, Ph.D. Mary E. Bartlett Daniel G. Colley, Ph.D. Dennis D. Juranek, D.V.M., M.Sc. Division of Parasitic Diseases Jonathan E. Kaplan, M.D. Division of HIV/AIDS Prevention National Center for Infectious Diseases in collaboration with: Robert Perciasepe, M.S. James R. Elder Stig E. Regli Paul S. Berger, Ph.D. Environmental Protection Agency Assessing the Public Health Threat Associated with Waterborne Cryptosporidiosis: Report of a Workshop Summary In September 1994, CDC convened a meeting to address the public health threat associated with waterborne cryptosporidiosis. Representatives from 40 states and from regulatory and public health agencies, water utility companies, and advocacy groups discussed approaches to avoiding unnecessary boil-water advisories (i.e., statements to the public advising persons to boil water before drinking it) and preventing and controlling waterborne crypto-sporidiosis. Work groups at the meeting addressed four issues: 1) surveillance systems and epidemiologic study designs; 2) public health responses when oocysts are detected in drinking water; 3) cryptosporidiosis in immunocom-promised persons; and 4) water sampling methods and interpretation of results. The work groups defined the problems associated with these issues and developed strategies that could be used initially to manage these problems. The work group discussions were summarized, and the conclusions were provided as either a) summaries of current knowledge concerning that issue or b) suggested ways to obtain the information needed to develop useful recommendations. The work group conclusions are for consideration by persons and organizations who must assist with these issues and by those who seek to advance understanding of waterborne cryptosporidiosis. INTRODUCTION In 1993, an outbreak of cryptosporidiosis affecting >400,000 persons occurred in Milwaukee. The magnitude of this outbreak, coupled with its association with water obtained from a municipal water plant that was operating within existing state and federal regulations, emphasized the need for a) improved surveillance by public health agencies to detect and prevent such outbreaks and b) coordination among interested groups and agencies to respond appropriately to such outbreaks. It also stimulated efforts to develop regulatory standards for Cryptosporidium in drinking water. To assist CDC and state public health departments in providing guidance on these issues, CDC's National Center for Infectious Diseases (NCID) convened a workshop entitled "Prevention and Control of Waterborne Cryptosporidiosis: An Emerging Public Health Threat" on September 22-23, 1994. The purpose of the workshop was to assemble persons from a variety of disciplines to discuss ways to minimize the public health risks associated with waterborne cryptosporidiosis. Invitations to the workshop were extended to CDC staff and representatives of state and local health departments, city and county water utilities, regulatory agencies, food and soft drink industries, groups representing immunosuppressed persons, and other groups. The objectives of the workshop were developed on the basis of discussions with these persons and organizations. The workshop agenda was designed to update participants regarding cryptosporidiosis and to separate into work groups to develop reports regarding four key issues: 1) surveillance and epidemiologic study designs; 2) public health responses when oocysts are detected in drinking water; 3) cryptosporidiosis in immunocompromised persons; and 4) water sampling methods, interpretation of data, and laboratory research priorities. Group leaders presented the work groups' reports during the final plenary session. Workshop organizers planned to publish these reports a) to summarize the public health issues associated with waterborne cryptosporidiosis; b) to suggest plans for responding appropriately to this threat; c) to suggest ways to develop the research base needed to determine the risks associated with Cryptosporidium oocysts in drinking water; and d) to stimulate discussions at all levels, especially at the local level, regarding prevention and management of waterborne cryptosporidiosis.