Shigella that causes diarrhea in children is on the rise in Cincinnati, Ohio, prompting a warning from city health officials.

Shigella is spread through contaminated food and water; people can also spread it if they don’t wash their hands after handling a diaper or using the bathroom.

There were 20 cases reported in July and August, compared to just one over the same period last year. Northern Kentucky is also seeing an uptick.

Although diarrhea is the most common symptom, Shigella can also cause vomiting, fever, nausea and bloody stool. Symptoms of Shigellosis, the infection caused by the Shigella bacteria, usually go away in five to seven days.