There are cases of norovirus, a miserable and highly contagious gastrointestinal virus rising sharply in parts of the United States this winter, according to government figures.

The latest numbers from the U.S. Centers for Disease Control and Prevention show 91 norovirus outbreaks were reported the week of Dec. 5, up from 69 outbreaks the last week of November.

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

Norovirus infection is characterized by sudden vomiting and diarrhea. outbreaks are often seen on cruise shipsin congregate living situations such as nursing homes and prisons, but also in schools and places where people are close to one another. earlier this month Hundreds of cruise passengers According to the CDC, which has recorded outbreaks of the virus on a total of 14 cruises this year, she contracted norovirus on three different ships. December saw the highest number of cruise ship outbreaks in a month compared to any other month so far in 2024.

Cases are also increasing on land. The Minnesota Department of Health recently recorded 40 norovirus cases, which is double the usual number in December. CBS News Minnesota reported.

Here are some things you should know about the virus.

According to the CDC, norovirus is the leading cause of foodborne illness in the United States, accounting for 58% of infections occurring annually in the country.

Dr. Former Baltimore Health Commissioner Leana Wen shared some best practices for how people can protect themselves from the disease on “Face the Nation with Margaret Brennan” on Sunday.

“Wash your hands really well, especially when going to buffets. “Wash your hands when you touch frequently touched surfaces, before you touch your mouth, before you touch your nose,” Wen said. “Norovirus is the most common foodborne illness here in the United States. It is very difficult to avoid once you have it in the family. And also don’t prepare food if you have vomiting, diarrhea, or stomach cramps because you don’t want to pass it on to other people.

Norovirus infections are caused by a group of viruses that spread easily, with just 10 virus particles capable of making someone sick, health experts say.

Approximately 2,500 norovirus outbreaks are reported annually in the United States. Outbreaks can occur any time of the year, but are most common between November and April.

In addition to vomiting and diarrhea, common symptoms include nausea, stomach pain, body aches, headaches and fever.

Most norovirus outbreaks occur when already infected people spread the virus to others directly, such as by sharing food or eating utensils. Outbreaks can also be spread through food, water or contaminated surfaces.

Illness caused by norovirus typically begins suddenly, with symptoms developing 12 to 48 hours after exposure to the virus. Most people feel better and fully recover within one to three days.

But even though there are 19 to 21 million cases of illness each year in the United States, norovirus still causes an average of 900 deaths and 109,000 hospitalizations per year, primarily in adults age 65 and older. It also results in 465,000 emergency room visits, mostly involving young children.

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

There are no medications to treat norovirus. To rehydrate, we recommend drinking water and other liquids, with the exception of coffee, tea and alcohol.

Anyone suffering from dehydration should seek medical attention. Symptoms of dehydration include decreased urine output, dry mouth and throat, and dizziness when standing. Dehydrated children may be unusually sleepy or fussy and cry little or not at all.

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

Scrubbing surfaces with household disinfectants can also help.