Norovirus symptoms and cases increased in Massachusetts in 2024, compared to 2023

The state reported 2,080 laboratory-confirmed cases of the virus in 2024 in preliminary data released last week by the Massachusetts Department of Public Health. That’s an increase of about 66% from the previous year, when the state reported 1,252 cases.

Cases occurring over the winter have so far exceeded that of the previous year, with 134 cases reported in November and 279 in December. In 2023, 52 cases were reported in November and 112 in December.

Public health officials say they are monitoring the increase in cases.

Nationally, virus cases are increasing in parts of the United States this winter, according to government data.

The most recent figures from the Centers for Disease Control and Prevention show that 91 norovirus outbreaks were reported during the week of December 5, compared to 69 outbreaks in the last week of November.

Figures from recent years show a maximum of 65 outbreaks reported in the first week of December.

Symptoms of norovirus include nausea, vomiting, diarrhea and abdominal cramps, according to state health officials. Although it is one of the most common causes of foodborne illness, the virus is difficult to detect in the laboratory and specialized testing for norovirus is usually only done in certain circumstances.

A DPH spokesperson said the rise in cases can be attributed in part to more modern testing methods that can detect multiple pathogens at once. They also noted that some testing devices have recently been found to be prone to false positives for norovirus.

Illness caused by norovirus usually begins suddenly and symptoms develop 12 to 48 hours after exposure to the virus. Most people feel better within one to three days and make a full recovery.

People of any age can become infected and become ill from norovirus. Young children, the elderly and people with weakened immune systems are most at risk, with dehydration from vomiting and diarrhea being the main concern.

There is no medication to treat norovirus. Rehydration is recommended by drinking water and other fluids, except coffee, tea and alcohol.

Health officials also recommend that people with norovirus symptoms stay home and practice good hand hygiene to help reduce the spread. Officials said washing with soap and water is preferable to hand sanitizer alone, which does not work well against norovirus.

People infected with the virus should not prepare or handle food for others for at least three days after symptoms disappear, authorities said.

Anyone suffering from dehydration should see a doctor. Symptoms of dehydration include decreased urination, dry mouth and throat, and feeling dizzy when standing. Dehydrated children may be unusually sleepy or fussy and cry with few or no tears.

Thorough and frequent hand washing is the best defense against norovirus during the peak winter season, scrubbing hands with soap and warm water for 20 seconds before meals.

Scrubbing surfaces with household disinfectants can also help.

Materials from the Associated Press were used in this report.

---

Camilo Fonseca can be contacted at camilo.fonseca@globe.com. Follow him on @fonseca_esq and on Instagram @camilo_fonseca.reports.