A spike in norovirus outbreaks is being reported across the United States this winter, with the Centers for Disease Control and Prevention (CDC) confirming 91 outbreaks during the week of December 5th. This represents a significant increase from the 69 outbreaks recorded at the end of November. According to the CDC data, in previous years there have been a maximum of 65 outbreaks in early December during the same period, making this increase particularly concerning. The surge comes during the peak season of the virus, which typically occurs from November to April.Norovirus, characterized by sudden vomiting and diarrhea, is highly contagious and tends to spread quickly in settings where people are in close contact with one another. These include cruise ships, nursing homes, schools and prisons.

What is Norovirus?

According to the CDC, norovirus is the most common cause of foodborne illness in the United States, accounting for 58% of these infections each year. The virus spreads easily, with as few as 10 virus particles able to cause illness. Around 2,500 norovirus outbreaks are reported annually in the United States, and although it can occur year-round, the virus is most common between November and April. The CDC notes that norovirus outbreaks are particularly common in places where people are in close quarters, such as schools, nursing homes, prisons and cruise ships.

In addition to vomiting and diarrhea, symptoms of a norovirus infection include nausea, stomach pain, body aches, headaches and fever. These symptoms usually appear within 12 to 48 hours of exposure to the virus and usually last 1 to 3 days. Most people recover fully, but the virus can cause severe dehydration, especially in vulnerable groups.

How is norovirus transmitted?

Norovirus is highly contagious and spreads in several ways. Most outbreaks occur when infected people spread the virus directly to others, such as by sharing food or eating utensils. The virus can also be transmitted through contaminated food, water or surfaces. Noroviruses are particularly resilient and can survive on surfaces for several days, making them easy to spread in community areas such as schools and nursing homes.

Who is most at risk?

While anyone can become infected with norovirus, certain groups are at higher risk of severe illness, particularly those who may be more susceptible to dehydration. These groups include:

• Small children
• Older adults, particularly those ages 65 and older
• People with weakened immune systems

Dehydration is the biggest concern for these individuals, as vomiting and diarrhea can quickly lead to fluid loss. In severe cases, medical intervention may be necessary to manage dehydration.

Norovirus treatment

There is currently no specific drug to treat norovirus. The disease usually goes away on its own within a few days. However, to avoid complications, it is important to drink enough fluids. Health experts recommend drinking liquids such as water, oral rehydration solutions, or clear broths. It is important to avoid drinks such as coffee, tea and alcohol as these can worsen dehydration.

If symptoms of dehydration occur, such as decreased urination, dry mouth, dizziness when standing, or excessive tiredness in children, medical attention should be sought immediately.

How to protect yourself from norovirus

As norovirus cases increase during the winter season, prevention is crucial. Here are some steps you can take to protect yourself:

• Wash your hands regularly: Scrub your hands with soap and warm water for at least 20 seconds, especially before eating, preparing food, or after using the bathroom.
• Disinfect surfaces: Clean and disinfect frequently touched areas such as kitchen countertops, bathroom sinks and doorknobs with household disinfectants that can kill norovirus.
• Avoid contact with infected people: Try to avoid close contact with people showing symptoms of norovirus, especially in crowded settings.
• Proper Food Handling: Ensure foods, especially shellfish, are prepared and cooked safely to avoid contamination.

By following these simple steps, you can significantly reduce your risk of contracting or spreading norovirus.

According to the CDC, norovirus causes 19 to 21 million illnesses in the United States each year. While the virus primarily affects children and older people, anyone can become infected. It results in an estimated 900 deaths, 109,000 hospitalizations and 465,000 emergency room visits annually, many of which affect young children.

Norovirus outbreaks can occur at any time, but there is a sharp increase in cases during the winter months. This is partly due to the higher likelihood of people gathering indoors, increasing the chance of transmission. Public health experts therefore strongly recommend practicing good hygiene, including frequent hand washing and disinfecting surfaces, especially during the colder months.