Pennsylvania department of health posts Shigella advisory

Outbreaks of shigellosis have been reported in Philadelphia, Allegheny, Dauphin, and York counties. Special attention to cleanliness is urged in daycare centers, among school-age children, and young adults. "Shigella is highly contagious, and the recent outbreaks suggest that this organism is spreading in the Commonwealth." The recent warmer weather may be a factor in its spread as well.

Most Shigella infections are caused by two bacterial organisms, Shigella sonnei and Shigella flexneri. The Shigella bacteria pass from one infected person to the next. According to the CDC:

"Shigella are present in the diarrheal stools of infected persons while they are sick and for up to a week or two afterwards. Most Shigella infections are the result of the bacterium passing from stools or soiled fingers of one person to the mouth of another person. This happens when basic hygiene and handwashing habits are inadequate and can happen during certain types of sexual activity. It is particularly likely to occur among toddlers who are not fully toilet-trained. Family members and playmates of such children are at high risk of becoming infected.
Shigella infections may be acquired from eating contaminated food. Contaminated food usually looks and smells normal. Food may become contaminated by infected food handlers who forget to wash their hands with soap after using the bathroom. Vegetables can become contaminated if they are harvested from a field with sewage in it. Flies can breed in infected feces and then contaminate food. Water may become contaminated with Shigella bacteria if sewage runs into it, or if someone with shigellosis swims in or plays with it (especially in splash tables, untreated wading pools, or shallow play fountains used by daycare centers). Shigella infections can then be acquired by drinking, swimming in, or playing with the contaminated water. Outbreaks of shigellosis have also occurred among men who have sex with men."
The Pennsylvania Department of Health recommends that persons with diarrheal illness do not attend or visit group settings particularly where children are present. Suspected cases should be confirmed by stool testing, then initiation of antibiotic. Since the bacteria may still be present in recovered patients, "children and staff members with Shigella must have two negative stool cultures, obtained at least 48 hours after the last dose of antibiotic and at least 24 hours apart, prior to returning to child- care facilities. The same restrictions apply to persons with Shigella who are healthcare workers or employed as food handlers. "

The most important ways to prevent Shigella transmission are good handwashing habits, practicing good general hygiene, and keeping surfaces clean and disinfected.

"Any questions or concerns regarding these recommendations should be directed to the Pennsylvania Department of Health at 1-877-PA-HEALTH. Further information on shigellosis is available on the PADOH web site at www.health.state.pa.us or the web site of the Centers for Disease Control and Prevention at www.cdc.gov."