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Removal of Giardia and Cryptosporidium in drinking water treatment: a pilot study. Water Research. 2003;37:1111–7. 38. Morita S, Namikoshi A, Hirata T, Oguma K, Katayama H, Ohgaki S, et al. Efficacy of UV irradiation in inactivating Cryptosporidium parvum oocysts. Appl Environ Microbiol. 2002;68:5387–93. Address for correspondence: Mark Reacher, Consultant Epidemiologist, Health Protection Agency-Communicable Disease Surveillance Centre, 61 Colindale Avenue, London NW9 5EQ, U.K.; fax: 44-0-20-8200-7868; email: Mark.Reacher@hpa.org.uk All material published in Emerging Infectious Diseases is in the public domain and may be used and reprinted without special per- mission; proper citation, however, is appreciated. Search past issues of EID at www.cdc.gov/eid Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 10, No. 6, June 2004 1015