For elementary school students, it’s probably not a good day when administrators send home stool collection kits. But that is part of a prolonged investigation in Wisconsin that has not been able to find the source of an E. coli O157:H7 outbreak.

By asking for stool specimens, however, Wisconsin’s Green County Health Department and the state Division of Public Health identified four Abe Lincoln Elementary School students infected with the same strain of E. coli O157:H7 responsible for 9 illnesses and one death between mid-August and mid-September.

No source has been identified for either the four recent cases or the nine earlier illnesses.

In mid-October, Wisconsin health officials hoped to test about 140 pre-kindergarten and kindergarten students at Abe Lincoln Elementary School in Monroe, sending the stool kits home with them with instructions to turn specimens into the health department.

The stool samples were then sent on to the Wisconsin State Laboratory of Hygiene for analysis.

Students who had not turned in their specimens were not allowed to attend school after Oct. 25.   

At least two of the earlier E. coli victims were students at Abe Lincoln. The school has since been cleaning and sanitizing and promoting hand washing.

Monroe School District officials say they’ve been told the Abe Lincoln Elementary School is not thought to be the source of the pathogen, which has now sickened 15 in the community.

Food Safety News invited Green County Health Department Director RoAnn Warden to comment about how many of the cases have connections to the school, but she declined the opportunity.

In September, medical privacy concerns were cited by the health department for not providing any information on the outbreak’s single fatality. Wisconsin media reports, however, said a 20-month old girl had died.

Since the outbreak began in mid-August, local and state health officials have been unsuccessful in identifying a common source that links the outbreak patients.

Residents have complained about the lack of information, but most parents are going along with the home stool test kits. Warden has warned that Shiga toxin-producing E. coli is a threat to the young, elderly and immune compromised.

Two of the original nine cases developed hemolytic uremic syndrome, which damages the kidneys.

The community is also being warned to keep children home from school if they come down with symptoms such as diarrhea, fever or vomiting and get them to a doctor.

The Monroe School District serves about 2,700 pupils in Green County. Monroe, with a population of almost 11,000, is known for Swiss cheese and beer with the oldest continually operating brewery in the Midwest.