Norovirus cases, a highly contagious stomach virus, are on the rise across parts of the United States this winter. According to recent data from the Centers for Disease Control and Prevention (CDC), 91 outbreaks of norovirus were reported during the week of December 5, up from 69 outbreaks in the last week of November. This is significantly higher than the maximum of 65 outbreaks typically recorded in early December in previous years.
Norovirus, often referred to as the stomach flu, causes sudden vomiting and diarrhea. Outbreaks are common in environments where people are in close quarters, such as cruise ships, nursing homes, schools, and jails.
What Is Norovirus Cases?
Norovirus is the leading cause of foodborne illness in the United States, accounting for 58% of such infections annually. It is caused by a group of viruses that spread easily, with as few as 10 viral particles capable of infecting someone.
There are approximately 2,500 norovirus outbreaks reported in the U.S. each year. While outbreaks can occur year-round, they are most frequent from November to April.
Symptoms of norovirus infection include vomiting, diarrhea, nausea, stomach pain, body aches, headaches, and fever.
How Does Norovirus Cases Spread?
Norovirus is primarily transmitted through direct contact with infected individuals or contaminated food, water, or surfaces. Sharing food, drinks, or eating utensils with an infected person is a common way the virus spreads.
The virus can also spread through unwashed hands, making personal hygiene a critical factor in preventing infection.
How Long Does the Illness Last?
Norovirus infections typically begin suddenly, with symptoms appearing 12 to 48 hours after exposure. Most individuals recover fully within one to three days.
Despite its short duration, norovirus causes an average of 19 to 21 million illnesses in the U.S. annually. It is responsible for approximately 900 deaths, 109,000 hospitalizations, and 465,000 emergency department visits each year, primarily affecting older adults and young children.
Who Is Most at Risk?
Norovirus can infect people of all ages, but certain groups are at a higher risk of severe illness. Young children, the elderly, and individuals with weakened immune systems are particularly vulnerable.
Dehydration is the most common complication of norovirus, caused by vomiting and diarrhea. Symptoms of dehydration include reduced urination, dry mouth and throat, dizziness when standing, and, in children, excessive fussiness or crying with few or no tears.
Anyone experiencing signs of dehydration should seek medical attention. Rehydration through water and electrolyte solutions is critical. However, beverages like coffee, tea, and alcohol should be avoided as they can worsen dehydration.
How Can You Protect Yourself?
Frequent and thorough handwashing is the most effective way to prevent norovirus infection, especially during the peak winter season. Hands should be scrubbed with soap and warm water for at least 20 seconds, particularly before meals or after using the restroom.
Cleaning surfaces with household disinfectants is also an important preventive measure. This helps eliminate the virus from high-touch areas such as countertops, doorknobs, and shared spaces.
The Road Ahead
As norovirus cases continue to rise this winter, public health officials emphasize the importance of maintaining good hygiene practices and monitoring symptoms. While most cases are mild and resolve quickly, the virus can lead to severe outcomes in vulnerable populations. Taking precautions and seeking prompt medical care in cases of dehydration can help minimize the impact of this highly contagious virus.
