E. coli O157 outbreak at daycare

So, today apparently is "blog about diarrhea" day. Hope no one's eating lunch. (One of the upsides of being a microbiologist is that we can talk about blood and gore and bodily fluids while we eat and no one gets grossed out. Or, perhaps, that's a downside. Anyway, I digress...)

Two still hospitalized, four treated after E. coli outbreak at daycare

Six confirmed cases of a serious E. coli infection and four additional "suspected" cases are being looked into by the [Tennessee] Department of Health, according to Debbie Hoy of the agency's Cookeville office this Tuesday. All of the infected children, ages 5 and under, attended the same Key Road day care facility operated by Paulette Colter, west of Lafayette.

"Most of the six children with confirmed cases have been released from Sumner Regional Medical Center or treated by their family doctor and sent home with their parents," said Ms. Hoy. Two children, a girl age three-years and a sixteen month old boy, remain in Vanderbilt Children's Hospital where they are receiving treatment.

Though they don't specifically identify it in that news story, others (such as this follow-up article) do note that the outbreak is caused by E. coli serotype O157:H7. This is a pathogen that was identified in the early 1980s, and rose to national attention in the 1990s following an outbreak due to contaminated hamburgers at Jack-in-the-Box restaurants.

Unlike your run-of-the-mill E. coli isolates, O157:H7 strains carry a toxin that can lead to bloody diarrhea and, in a small number of cases, result in the development of a condition called hemolytic uremic syndrome. This, in turn, can lead to renal failure and death, particularly in children.

The bacterium can be present in a number of foods. Previous outbreaks have been associated with a variety of foods, including unpasteurized milk, juice, and cider (in addition to the aforementioned hamburger). Petting zoos and local fairs have also been the epicenters of outbreaks: the bacterium can be carried in the intestines of healthy cattle, which often serves as the source of contamination. Once a child, especially, becomes infected, they can act as a reservoir and spread it along to other people:

One child became ill nearly a week before other children at the facility began to show symptoms. Officials speculate that the first child may have infected toys, linens or other items from which the other children were infected. The bacterial infection is so aggressive that simple hand washing is not enough to prevent its spread, especially if hand to mouth activity immediately follows the initial exposure.

Because the virulent strain of E. coli is easily transmitted from person-to-person, day care center operator Paulette Colter voluntarily closed her facility last Friday when additional children showed symptoms of infection.

Young children can carry the bacterium for several days to weeks after symptoms resolve, and because their hygiene habits often aren't exactly the best, it's easy to see why such an outbreak can be a real problem at a day care center. The second story notes that this index child was initially sent home due to his diarrhea, but was given anti-diarrheal medicines and sent back the next day. Hard to say whether keeping him home at that point would have stemmed the outbreak or whether he'd already infected other children. The story also notes that a 17-month-old remained hospitalized with kidney failure. My grandmother was hospitalized with this several years ago, so I know how horrible it can be, and it certainly is even more so with a child that young.