Woodbury County Health officials are urging those sick with diarrhea to stay home from work and school to prevent the spread of shigellosis, an extremely contagious bacterial infection of the lining of the intestines.

Siouxland District Health Deputy Director Tyler Brock said 42 cases of the non-life-threatening illness transmitted through human contact have been reported recently in the county, and he only expects those numbers to grow. Last year Woodbury County recorded a single case of shigellosis.

Brock said only about 20 of the cases were diagnosed; the others, he said, were identified during phone interviews with family members suffering similar symptoms. Patients include school and daycare-age children, as well as adults. None of the patients have been hospitalized as a result of the illness.