Cryptosporidiosis: An Outbreak Associated with Drinking Water Despite State-of-the-Art Water Treatment
Publication: Annals of Internal Medicine
Volume 124, Number 5
Submit a Comment
Contributors must reveal any conflict of interest. Comments are moderated. Please see our information for authorsregarding comments on an Annals publication.
Abstract
Objective:
To determine the magnitude and source of an outbreak of cryptosporidiosis among persons with human immunodeficiency virus (HIV) infection and to determine whether the outbreak extended into the immunocompetent population.
Design:
Matched case–control study and environmental investigation.
Setting:
Clark County, Nevada.
Participants:
Adults with HIV infection (36 case-patients with laboratory-confirmed Cryptosporidium parvum infection and 107 controls), matched by physician or clinic and by CD4+ cell count category.
Measurements:
Potential risk factors for infection, death rates, and data on water quality.
Results:
Review of surveillance and microbiology records identified 3 cases of cryptosporidiosis in 1992 (the first year that cryptosporidiosis was reportable in Nevada), 23 cases in 1993, and 78 cases in the first quarter of 1994. Of the 78 laboratory-confirmed cases in the first quarter of 1994, 61 (78.2%) were in HIV-infected adults. Of these 61 adults, 32 (52.5%) had died by 30 June 1994; at least 20 of the 32 (62.5%) had cryptosporidiosis listed on their death certificates. In the case–control study, persons who drank any unboiled tap water were four times more likely than persons who drank only bottled water to have had cryptosporidiosis (odds ratio, 4.22 [95% CI, 1.22 to 14.65]; P = 0.02). For persons with CD4+ cell counts less than 100 cells/mm3, the association between tap water and cryptosporidiosis was even stronger (odds ratio, 13.52 [CI, 1.78 to 102.92]; P = 0.01). Additional data indicate that this outbreak also affected persons who were not infected with HIV. No elevated turbidity values or coliform counts and no Cryptosporidium oocysts were found in testing of source (Lake Mead) or finished (treated) water during the study period, but so-called presumptive oocysts were intermittently found after the investigation in samples of source water, filter backwash, and finished water.
Conclusions:
A cryptosporidiosis outbreak was associated with municipal drinking water, despite state-of-the-art water treatment and water quality better than that required by current federal standards. This outbreak highlights the importance of surveillance for cryptosporidiosis and the need for guidelines for the prevention of waterborne-Cryptosporidium infection among HIV-infected persons.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Juranek DD. Cryptosporidiosis: sources of infection and guidelines for prevention. Clin Infect Dis. 1995; 21(Suppl 1):S57-61.
2.
O'Donoghue PJ. Cryptosporidium and cryptosporidiosis in man and animals. Int J Parasitol. 1995; 25:139-95.
3.
Badenoch J. Cryptosporidium in Water Supplies: Report of the Group of Experts. London: Her Majesty's Stationery Office; 1990.
4.
Mac Kenzie WR, Hoxie NJ, Proctor ME, Gradus MS, Blair KA, Peterson DE, et al. A massive outbreak in Milwaukee of cryptosporidium infection transmitted through the public water supply. N Engl J Med. 1995; 331:161-7.
5.
Hayes EB, Matte TD, O'Brien TR, McKinley TW, Logsdon GS, Rose JB, et al. Large community outbreak of cryptosporidiosis due to contamination of a filtered public water supply. N Engl J Med. 1989; 320:1372-6.
6.
Moore AC, Herwaldt BL, Craun GF, Calderon RL, Highsmith AK, Juranek DD. Surveillance for waterborne disease outbreaks—United States, 1991-1992. MMWR CDC Surveill Summ. 1993; 42:1-22.
7.
Kleinbaum DG, Kupper LL, Morgenstern H. Epidemiologic Research: Principles and Quantitative Methods. Belmont, CA: Lifetime Learning Publications; 1982; 159-80.
8.
U. S. Environmental Protection Agency. 40 CFR; parts 141 and 142; Drinking water; national primary drinking water regulations; filtration, disinfection; turbidity, Giardia lamblia, viruses, Legionella, and heterotrophic bacteria; final rule. Federal Register. 1989; 54:27486-541.
9.
Clancy JL, Golinitz WD, Tabib Z. Commercial labs: how accurate are they? Journal of the American Water Works Association. 1994:86; 89-97.
10.
Musial CE, Arrowood MJ, Sterling CR, Gerba CP. Detection of Cryptosporidium in water using polypropylene cartridge filters. Appl Environ Microbiol. 1987; 53:687-92.
11.
American Society for Testing and Materials. D-19 proposal P229. Proposed test method for Giardia cysts and Cryptosporidium oocysts in low-turbidity water by a fluorescent antibody procedure. In: 1993 Book of ASTM Standards: Water and Environmental Technology. Philadelphia: American Society for Testing and Materials; 1993:899-909.
12.
Boyce TG, Pemberton AG, Addiss DG. Cryptosporidium testing practices among clinical laboratories in the United States. Pediatr Infect Dis J. 1996; 15:87-8.
13.
Current WL, Garcia LS. Cryptosporidiosis. Clin Microbiol Rev. 1991; 4:325-58.
14.
Assessing the public health threat associated with waterborne cryptosporidiosis: report of a workshop. MMWR Morb Mortal Wkly Rep. 1995; 44(RR-6):1-19.
15.
LeChavallier MW, Norton WD, Lee RG. Occurrence of Giardia and Cryptosporidium spp. in surface water supplies. Appl Environ Microbiol. 1991; 57:2610-6.
16.
LeChavallier MW, Norton WD, Lee RG. Giardia and Cryptosporidium spp. in filtered drinking water supplies. Appl Environ Microbiol. 1991; 57:2617-21.
17.
LeChavallier MW. Preventing waterborne disease: is your system at risk? American Water Works Association Satellite Teleconference Participant Guide Addendum. Denver: American Water Works Assoc; 1994:2-3.
18.
Dupont HL, Chappell CL, Sterling CR, Okhuysen PC, Rose JB, Jakubowski W. The infectivity of Cryptosporidium parvum in healthy volunteers. N Engl J Med. 1995; 332:855-9.
19.
Haas CN, Rose JB. Reconciliation of microbial risk models and outbreak epidemiology: the case of the Milwaukee outbreak. In: Proceedings of the 1994 Annual Conference: Water Quality. Denver: American Water Works Assoc; 1994:517-23.
20.
Sorvillo FJ, Lieb LE, Kerndt PR, Ash LR. Epidemiology of cryptosporidiosis among persons with acquired immunodeficiency syndrome in Los Angeles County. Am J Trop Med Hyg. 1994; 51:326-31.
21.
Sorvillo F, Lieb LE, Nahlen B, Miller J, Mascola L, Ash LR. Municipal drinking water and cryptosporidiosis among persons with AIDS in Los Angeles County. Epidemiol Infect. 1994; 113:313-20.
22.
Ciesielski C, Kaplan J, Mays M, Ward J, Juranek D. Cryptosporidiosis in AIDS patients in the United States—relationship to municipal water supplies? [Abstract]. Program and Abstracts of the 2nd National Conference on Human Retroviruses and Related Infections. Washington, DC, 30 January 1995-6 February 1995.
23.
Assessment of inadequately filtered public drinking water—Washington, DC, December 1993. MMWR Morb Mortal Wkly Rep. 1994; 43:661-9.
Information & Authors
Information
Published In
Annals of Internal Medicine
Volume 124 • Number 5 • 1 March 1996
Pages: 459 - 468
History
Published in issue: 1 March 1996
Published online: 15 August 2000
Keywords
Copyright
© 1996 American College of Physicians.
Authors
Metrics & Citations
Metrics
Citations
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. For an editable text file, please select Medlars format which will download as a .txt file. Simply select your manager software from the list below and click Download.
For more information or tips please see 'Downloading to a citation manager' in the Help menu.
Download article citation data for:
Cryptosporidiosis: An Outbreak Associated with Drinking Water Despite State-of-the-Art Water Treatment. Ann Intern Med.1996;124:459-468. doi:10.7326/0003-4819-124-5-199603010-00001
Cryptosporidiosis: An Outbreak Associated with Drinking Water Despite State-of-the-Art Water Treatment. Ann Intern Med.1996;124:459-468. doi:10.7326/0003-4819-124-5-199603010-00001
View More
Login Options:
Purchase
You will be redirected to acponline.org to sign-in to Annals to complete your purchase.
Access to EPUBs and PDFs for FREE Annals content requires users to be registered and logged in. A subscription is not required. You can create a free account below or from the following link. You will be redirected to acponline.org to create an account that will provide access to Annals. If you are accessing the Free Annals content via your institution's access, registration is not required.
Create your Free Account
You will be redirected to acponline.org to create an account that will provide access to Annals.
Comments
0 Comments