First came the fires. Then, there was ash and contaminated water. Now, some survivors of the Southern California wildfires are dealing with outbreaks of norovirus and other stomach ailments at a shelter set up to help evacuees.

An outbreak of the norovirus has been reported at the Pasadena Evacuation Center, officials confirmed. The Pasadena Public Health Department said that three cases of the norovirus were confirmed at the Pasadena Convention Center shelter on Friday morning.

The Health Department confirmed three people at the shelter tested positive for the virus among a cluster of 28 people suffering from acute gastrointestinal illness.

Norovirus, commonly called the stomach flu, is a gastrointestinal virus causing vomiting, diarrhea, abdominal cramping and a fever.