The Cuyahoga County Board of Health has issued a health advisory for the Orthodox Jewish community of Cleveland relating to the current outbreak of Shigella, a highly infectious bacterial infection causing diarrhea. As of Jan 20 there were 21 confirmed cases. However, this typically represents a tiny portion of actual cases, as many with mild symptoms (and some do not experience any symptoms) do not seek medical care and many others are never confirmed by culture. In general, it is estimated that the actual number of cases may be 30 times as many laboratory confirmed cases. Children from several Jewish schools have been affected, and it is likely to have affected some adults as well. In large scale outbreaks in the past, adults have accounted for 15% of confirmed cases, with slightly more than half under the age of 5.
Shigella is highly contagious, with tiny numbers of organisms able to cause infection. The best protection is frequent handwashing with warm water and soap for 20 seconds. It is transmitted through the fecal-oral route, i.e. the bacteria is passed from the stool, and some amount is eventually passed to the mouth of someone else. As you would guess, this is more common in day care centers and anywhere there are large numbers of children who are not fully toilet trained and/or do not take care of themselves properly after using the bathroom (wiping/washing). Orthodox families often have multiple kids in diapers/not fully trained putting them at higher risk. Also, younger kids spreading disease are likely to have multiple siblings to pass it on to. Shabbos also poses difficulties, as supplies of liquid soap must be available wherever people wash, and there is the difficulty of using pre-moistened wipes on Shabbos. Proper precautions must be taken to ensure proper hygiene to reduce transmission of this illness.
Ritual handwashing is typically done outside the bathroom. It is important for people to wash with warm water and soap before leaving the bathroom. Otherwise germs are being left on the door handles. Handwashing stations should also be equipped with soap (or water-less washing gel), as washing with cold water and a kli is not sufficient for physical hygiene.