An outbreak of Norovirus in Yolo County has expanded to nearly a thousand known cases.
The Yolo County Health and Human Services Agency says more than 950 students, teachers and staff are currently sick with stomach cramps, vomiting and/or diarrhea throughout the county.
The number of sick people is increasing every day at a very alarming rate, according to the agency.
Testing has confirmed it is Norovirus, a highly-contagious illness that's commonly spread through touching surfaces contaminated with the virus, close contact with someone who is infected or eating contaminated food.
Norovirus particles can even float through the air and then settle on surfaces, spreading contamination.
People can transfer the illness to others for at least three days after being sick.
The outbreak is affecting people at UC Davis and the following school districts; Davis Joint, Esparto Unified, Washington Unified, Woodland Joint Unified, and Winters Joint Unified.