Officials confirmed an outbreak of norovirus at a shelter housing wildfire evacuees in Chico, the main city near Paradise, California, on Wednesday evening. Another outbreak is suspected at a second shelter.

Lisa Almaguer, the public information officer for the Butte County Department of Public Health said lab tests confirmed the outbreak at Neighborhood Church where about 170 evacuees were staying.

Fifteen to 20 of them have fallen ill and are being treated at the shelter away from the other evacuees.

“They have separate restroom facilities and they are being cared for by public health nurses,” Almaguer said, Mercury News reported. “Norovirus is not uncommon, especially this time of year, and it’s especially not uncommon for a shelter situation where you have hundreds of people living in very close quarters.”

According to the Centers for Disease Control and Prevention, norovirus is highly contagious and can cause vomiting and diarrhea.

The Sacramento Bee reported that evacuees staying at the nearby Oroville Church are also showing symptoms of norovirus, however, the lab tests haven’t confirmed it yet. Around 160 people were staying at the shelter.

Though the shelter manager Diane Shoen did not confirm the outbreak, other evacuees said they had heard of one or more evacuees being treated.

“They want us to keep washing our hands and not shake hands and use Purell (sanitizer) before dinner,” said Rich Montgomery, an evacuee, adding that he also saw a resident vomiting.

Don Martin from Paradise said though he heard people talking about an illness, he wasn’t scared as according to him if the disease was uncontrollable, “you’d see sick people everywhere.” Cynthia Shaw, a Red Cross spokeswoman said norovirus is common in situations like camps and schools where people are in close contact.

“The best way to stop the spread of the virus is hand washing, food safety and isolation of those who are sick,” Shaw said adding the workers in the camps have taken the required steps.

Meanwhile, fire officials said the death toll from the Camp Fire in Butte County could rise above 100. On Tuesday, search crews found six more bodies taking the total toll to 56 with some 130 people still missing.

"We want to be able to cover as much ground as quickly as we possibly can. This is a very difficult task,” Butte County Sheriff Kory Honea said, CBS News reported.

Camp Fire has burned 138,000 acres and destroyed 10,321 structures, with only 35 percent contained.

"The town of Paradise in Butte County has experienced the worst fire for death toll and loss of structures and businesses homes everything of any other fire in California history. I stood in front of some of you and others here on stage on Sunday night and said that it was the second most deadly. It is by far the most deadly single fire in California history. And it's going to get worse unfortunately," Cal Fire Strategic Planning Chief Thom Porter said, ABC 7 News reported.