It’s one of the most basic rituals of hygiene.

Most of us are taught from a very early age that hand-washing is an easy, essential way of keeping ourselves clean and healthy. But residents of Flint, Michigan and surrounding areas have been forgoing this common practice out of fear of the water’s toxicity. Genesee county, of which Flint is a the largest city, and the adjacent county of Saginaw combined have experienced an outbreak of 131 cases of a contagious, preventable bacteria gastrointestinal disease, according to the Detroit News.

Shigellosis (named after the bacteria that causes it, Shigella) is usually not lethal, but it’s also certainly not pleasant. It’s a bloody diarrheal disease transmitted via tiny amounts of contaminated fecal matter. It typically lasts about a week, but can also cause patients to feel like they have to go to the bathroom even when they have no more waste in their systems. Additionally, the US Centers for Disease Control (CDC) also notes that “may be several months before [patients] bowel habits are entirely normal.”

In 2013, there were just under five cases reported per every 100,000 people in America. The outbreak in Michigan far exceeds that number, and it’s likely because residents in the area are afraid to use their tap water, which was found to have toxic levels of lead, a heavy metal that can cause neurological problems when it builds up in the body, in 2015. Even though the water was deemed safe for consumption with a proper filter, people in the area are still scared to wash their hands at all, according to the Washington Post.

Instead, they’re cleaning themselves using baby wipes—aren’t nearly as effective as disinfectant as good old-fashioned scrubbing—which should take about 20 seconds to ensure that any potential pathogens are washed down the drain.

“Some people have mentioned that they’re not going to expose their children to the water again,” Jim Henry, Genesee County’s environmental health supervisor, told CNN.

In this case linger fear of lead poisoning is leading to a three-fold increase of a preventable diarrheal disease. ”If people aren’t washing their hands, [Shigellosis] runs through the whole county,” he said.