No abstract

A study of persons with laboratory-confirmed sporadic Campylobacter jejuni infection and of controls matched for age and sex in Colorado in the summer of 1981 yielded odds ratio estimates significantly greater than I for the following risk factors: drinking raw water (10.74), drinking raw milk (6.93), eating undercooked chicken (2.77), and living in a household with a cat (3.21).

In November 1981, an outbreak of waterborne giardiasis occurred at a popular ski resort in Colorado. Stratification of illness by consumption of municipal tap water showed a striking dose-response, with an attack rate of 42 per cent among persons who drank six or more glasses of water per day. Filtered water samples revealed Giardia cysts in specimens both before and after treatment, and several deficiencies were found in the water treatment facility. Residents who had lived in the area >2 years had a lower attack rate for illness than short-term residents. (Am J Public Health 1984; 74:602-604.)

Transmission of hepatitis A has been described in many settings, although few outbreaks have been reported among illicit drug users. We report six unrelated outbreaks of hepatitis A among users of marijuana and intravenously administered methamphetamine. Although the exact mode of transmission could not be IntroductionOutbreaks of hepatitis A infection have resulted from common-source food and water-borne transmission and from