Now, there's another disease that has health leaders on alert.
"Norovirus is very, very contagious," said Leticia Berber, a health educator with the Fresno County Department of Public Health. "If you don't wash your hands after changing a diaper, going to the bathroom, handling raw food, you can catch that norovirus."
Norovirus is an illness that causes vomiting or diarrhea.
The CDC says there are about 2,500 norovirus outbreaks that are reported each year in the U.S.
Data shows that for the week of December 5, 91 cases of the disease were reported, exceeding numbers from previous years.
Fresno County is also seeing an uptick in norovirus infection.
"We do see an increase of norovirus activity during the winter months," said Berber. "We are seeing it regionally."
Health leaders say norovirus outbreaks can happen throughout the year but are most common from November to April. Anyone is susceptible to catching the illness.
"We really have to watch out for our vulnerable population," said Dr. Jessica McFarland, an Infectious Disease Physician with UCSF Fresno. "That would be our children and our elderly. People who are sensitive to dehydration."
She tells Action News that norovirus can spread in places where there are a lot of people, whether that's restaurants or even healthcare settings.
"If you're in large group settings, you're touching things, you're sharing, you're sharing the same food and water or drinks, that's how it can spread very quickly," said Dr. McFarland.
Health experts say washing your hands and cleaning surfaces often can help prevent the spread of norovirus, as well as keep the community healthy.
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