A new study finds swimming, having a private well or septic system, and other factors not involving food consumption were major risk factors for bacterial intestinal infections not occurring in outbreaks.
Outbreaks linked to food, such as the current Salmonella outbreak involving peanut butter that has sickened more than 500 people in 43 states, account for only about 10 percent of intestinal infections, which are medically termed as enteric infections. The new study, in the February 15 issue of The Journal of Infectious Diseases, now available online, suggests that methods for controlling bacterial enteric outbreaks may not be completely relevant to controlling the other 90 percent or so that occur sporadically.
In a USDA-sponsored, two-year study of children and adolescents in three Washington state counties, the investigators, led by Donna M. Denno, MD, MPH, of the University of Washington, and Phillip I. Tarr, MD, of Washington University, St. Louis, interviewed 296 patients, aged 19 years or less, who were infected at some point between 2003 and 2005 and who were matched with 580 uninfected controls. Laboratory tests identified the bacteria responsible for infection as Campylobacter in 151 cases, Salmonella in 86 cases, Escherichia coli O157 in 39 cases, and Shigella in 20 cases.
Analysis of the data suggested that non-food exposures pose risks of sporadic bacterial enteric infection that are comparable in magnitude to those of food exposures. In particular, one surprise was a strong association with swimming and other forms of recreational water exposure for all four types of infection. Another surprising finding was an association with private well water (Salmonella) and septic system (Salmonella and E. coli O157) exposures. Hand washing practices and daycare attendance, however, were not associated with an increased risk of infection, also a surprise. Finally, far
|Contact: Steve Baragona|
Infectious Diseases Society of America