"The Numbers: CDC reports 91 norovirus outbreaks in early December, up from 69 in November, marking the highest level since 2012. The virus causes 19-21 million illnesses annually, resulting in 109,000 hospitalizations and 900 deaths. What to Know: The highly contagious virus spreads through contaminated food, surfaces, or direct contact, with no available medication. Young children, elderly, and immunocompromised individuals are most at risk, with frequent handwashing being the best defense."