- “Winter vomiting disease” is on the rise across the United States, with norovirus cases surging since mid-October.
- Wastewater surveillance and CDC testing indicate that norovirus is spreading earlier and faster than usual, particularly in Louisiana, Michigan, and Indiana.
- The virus spreads easily through contaminated food, water, hands, and surfaces, and symptoms can appear within a short period.
- Preventing infection from norovirus includes proper handwashing, disinfecting surfaces, avoiding shared food or utensils, and staying home and hydrated if you become sick.
Rising norovirus cases across the United States have many people wary of contracting the so-called “winter vomiting disease.”
Data from WastewaterSCAN, a national monitoring program run by Stanford and Emory University, shows that norovirus levels have been rising since mid-October, with notable increases detected in Louisiana, Michigan, and Indiana.
Despite this increase, norovirus outbreak trends are currently lower than last year, with 235 norovirus outbreaks reported during the same time period in 2024.
Norovirus is a highly contagious virus that spreads rapidly through contaminated food, water, hands, and surfaces.
With holiday travel and crowded indoor gatherings underway, conditions are ideal for the rapid transmission of this infectious disease, known to cause unpleasant gastrointestinal side effects.
Here’s what you need to know about the winter surge in norovirus cases and how to protect yourself.
The time of year plays a significant role in the current surge in norovirus cases.
“Norovirus usually increases during the cold months when individuals have more indoor time and are in proximity to each other at places like school or work; this allows the virus to be easily passed from individual to individual,” Blen Tesfu, MD, physician and medical advisor at Welzo, told Healthline.
Holiday travel and an increase in social gatherings can also contribute to the spread of norovirus.
“Close quarters and sharing food or being on crowded buses and trains, as well as touching so many things, create an environment that will allow Norovirus to spread before you even realise you’ve come into contact with someone who has it,” Tesfu said.
Cold weather can also affect how well our immune system defends us. Lower vitamin D levels in winter and drier air can weaken natural immune barriers, making it easier for viruses like norovirus to spread.
Colder temps play a part, too. “The virus survives better in cool, dry air,” Paria Sanaty Zadeh, PharmD, clinical pharmacist at Drugwatch, told Healthline.
Many people associate norovirus outbreaks with cruise ships, but the virus can also present in various other settings, including schools and nursing homes.
Norovirus infection may lead to telltale symptoms of vomiting and diarrhea, as the virus primarily affects the gut.
“Unlike the flu, norovirus targets the gut,” Zadeh said. “It’s a viral gastroenteritis, [or] what people call a ‘stomach bug,’ even though the virus affects the small intestine more than the stomach.”
Norovirus typically has an abrupt onset, manifesting as vomiting and diarrhea, and is highly contagious.
“Getting it from contaminated hands or food is most common, either touching something contaminated and then touching your mouth, or eating something contaminated,” Zadeh said.
“You can get it from touching a surface that wasn’t cleaned well after someone was sick, then touching your mouth. And you only need a tiny amount of the virus to get infected. It moves and spreads easily.”
The incubation time for norovirus infection is fairly short.
Symptoms typically begin
“Common symptoms that are easily identifiable include vomiting, diarrhea, abdominal pain, and nausea, but you may also experience other symptoms like headaches, general fatigue, slight fever, or generalised body aching,” Tesfu said.
Zadeh said that vomiting and diarrhea are often the first symptoms, followed by stomach cramps, nausea, and sometimes a low grade fever within a day or two of exposure.
Most norovirus symptoms usually resolve within
There are several ways to protect yourself from norovirus, particularly when you are in close proximity to others.
Proper hand hygiene is the most effective way to prevent norovirus. Washing with soap and water is essential, as alcohol-based sanitizers are less effective against this virus.
It’s also a good idea to avoid sharing food, drinks, or utensils, and to disinfect high-touch surfaces with a bleach-based cleaner, since norovirus can survive on surfaces for several days.
If someone in your home is sick, ensure that you wash any affected clothing and bedding on a hot cycle and handle the items carefully to prevent the spread of viral particles.
If you contract norovirus, prioritize hydration and rest. There are currently no medications that can eliminate the infection, but some over-the-counter options, such as electrolytes, can be helpful.
“Drink small amounts of fluid (for example, 1–2 tablespoons) at a time, to replace what is lost in stool as well as limit the risk of vomiting when trying to drink larger volumes of liquid; drinking such small amounts may also reduce nausea symptoms,” Tesfu said.
Try to rest when you feel tired and avoid activities that require physical exertion, such as work or exercise. Most people need to rest for the first 24 to 48 hours while symptoms are at their worst, and can then gradually resume normal activity as their energy returns.
Prioritizing sleep, keeping activity to a minimum, and giving your body uninterrupted downtime will help prevent dehydration and support recovery.
If you experience worsening symptoms, such as severe weakness or dehydration, or have a serious preexisting medical condition, you should seek immediate medical attention.
