Norovirus outbreaks have significantly increased in the United States, with recent reports indicating a rise in cases. As of December 5, 2024, there were 91 reported cases, up from 69 in the previous month, marking a notable surge compared to previous years.
December has seen the highest number of norovirus outbreaks on cruise ships in 2024, resulting in hundreds of infections across multiple vessels.
In Minnesota, 40 cases were reported in December, which is double the number observed in the same month in previous years.
Key Background:
The highly contagious gastrointestinal illness norovirus is seeing sharply rising cases across the United States this winter, the latest figures from the Centers for Disease Control and Prevention show. The latest statistics, for the week ending December 5, reveal a dramatic surge in reported outbreaks, with 91 documented cases, compared with 69 reported in the last week of November. Historically, outbreaks during early December have been typically lower, with a maximum of 65 cases in previous years.
Norovirus, sometimes called the “winter vomiting bug,” causes sudden onset of vomiting and diarrhea. It spreads fast in close populations, such as cruise ships, schools, nursing homes, and correctional facilities. Already this winter, several major outbreaks have been reported on cruise ships, with hundreds of passengers stricken across three separate voyages. According to the CDC, it was reported that 14 outbreaks occurred in cruise ships in 2024, and December led the list of months with most outbreaks this year.
Land cases are also on the rise. Just recently, the Minnesota Department of Health reported 40 cases of norovirus in December. The norovirus infection rate remains at the top for causing foodborne illnesses in the U.S. This occurs as it causes 58% of foodborne infections yearly.
Health experts, such as former health commissioner of Baltimore, Dr. Leana Wen, recommend frequent and proper hand washing in order to prevent infection, especially before eating, after touching shared surfaces, or buffets. “Norovirus is very hard to avoid once it’s in your family,” she explained, stressing that food preparation during symptom times should be avoided in order to prevent transmission.
The viruses belong to a group of relatively easily transmitted viruses; and only 10 viral particles can cause illness. Outbreaks could occur at any time of the year; but the major outbreak usually happens during the period November to April. Most people will experience nausea, stomach discomfort, fever, body aches, and, of course, vomiting and diarrhea. Most patients recover within one to three days, though the virus can cause severe dehydration, especially in young children, older adults, and those with weakened immune systems.
Norovirus causes around 2,500 outbreaks annually, which leads to an estimated 900 deaths, 109,000 hospitalizations, and 465,000 emergency department visits. Since there is no specific treatment for the virus, one should maintain hydration. Patients with dehydration symptoms should be taken to the doctor. The best precautions against the spread of norovirus during this peak winter season are frequent hand washing and disinfecting of surfaces.
