Self-reported illness among travelers to the Russian Far East.

This study evaluated the risk of travelers to the Russian Far East developing acute gastrointestinal or respiratory symptoms. Passengers and crew on 10 commercial airline flights from the Russian Far East to the United States were asked to complete a health questionnaire that asked age, sex, country of residence, length of stay, foods and beverages consumed, and about gastrointestinal or "flu" symptoms. Questionnaires were returned by 353 of 662 persons (53.3 percent). The most frequently reported symptoms were diarrhea (N = 18; 5.1 percent) and "flu" symptoms (N = 15; 4.2 percent). Among those people who reported symptoms, most were sick for 3 days or less, although 10 (27.0 percent) were still sick at the time that they entered the United States. Age and sex were not associated with symptoms. Persons who drank untreated tap water were more likely to have gastrointestinal symptoms (relative risk = 2.7; 95 percent confidence interval = 1.2, 5.9) while those who drank bottled or canned fruit juice were protected (relative risk = 0.4; 95 percent confidence interval = 0.2, 0.8). The incidence of "flu" symptoms was similar to the rate for the general population of the United States while the incidence of gastrointestinal symptoms was increased and only slightly less than the rate among travelers to developing countries. Travelers may wish to restrict consumption of untreated tap water and increase consumption of fruit juices. Additional work is needed to identify the pathogens responsible for acute illness among travelers to the Russian Far East.