It’s the scariest time of year. One moment you’re gearing up for a day of fall activities and next thing you know, you’re clinging to a porcelain toilet with full body aches. Within 24 hours, the whole house is sick.
Like the masked Michael Myers in a “Halloween” reboot, norovirus is back again. A spokeswoman for the state health department said New Jersey has seen an uptick in recent reported outbreaks of norovirus, an extremely contagious illness that causes a host of nasty gastrointestinal issues.
So far in 2025, there’s been a total of 238 outbreaks, according to preliminary state data. By comparison, there were a total of 195 outbreaks reported in 2024. In 2023, 189 outbreaks were reported.
Norovirus outbreaks occur throughout the year but are most common from November to April. However, aggressive strains of the virus may be contributing to an earlier onset of the norovirus season, according to research published by the Centers for Disease Control and Prevention in June.
What is norovirus?
Often called the “stomach flu” or “stomach bug,” norovirus causes painful stomach cramps, nausea, vomiting and diarrhea, according to the CDC.
Unlike other illnesses that may develop over several days or weeks, it “can be abrupt,” said Dr. Stefan Hagmann, section chief of pediatric infectious diseases at Joseph M. Sanzari Children’s Hospital located at Hackensack University Medical Center.
Symptoms usually develop within 12 to 48 hours after being exposed, according to the CDC.
“You could be woken up in the middle of the night and your child starts to throw up and then rush to the toilet. That’s how rapid this can happen. In a way, you go to bed and you don’t expect anything to happen, and then all of a sudden you’re standing in the middle of this mess,” said Hagmann.
How does it spread?
The virus spreads easily and quickly through:
Direct contact with an infected person.
Contaminated food and beverages.
Touching contaminated objects or surfaces.
The virus is most commonly reported in healthcare facilities. Over half of all outbreaks reported in the United States occur in long-term care facilities, according to the CDC.
Cruise ships are also a hotbed for viral outbreaks. The convergence of travelers from all over the world together in a crowded, semi-enclosed space can facilitate the spread of germs.
In September, nearly 100 people aboard the Royal Caribbean International’s Serenade of the Seas ship were sickened by norovirus, marking the 19th outbreak of stomach illness on a cruise ship this year.
By comparison, in 2024 there were 18 and in 2023, 14.
More than 90% of gastrointestinal illness outbreaks on cruise ships are due to norovirus, according to the CDC’s Maritime Illness Database and Reporting System. For international cruise ships porting in the U.S. during 2006–2019, an average of 12 outbreaks occurred each year.
While the most severe symptoms usually only last 48 hours, individuals can still spread the virus for two weeks or more after feeling better, according to the CDC.
How is it treated?
There’s no specific medicine used to treat people with norovirus. Since it’s a virus and not a bacterial infection, antibiotics won’t help, said Hagmann.
Most people with the stomach bug get better in one to three days. But for some people, it can become a serious illness. Since the virus causes excessive diarrhea and vomiting, it can lead to severe dehydration, especially in young children and older adults.
Each year in the U.S., norovirus causes an average of 900 deaths, according to the CDC.
“It’s a simple illness, but if you live in a household where there are immunocompromised persons, then it’s something to really be aware of, to help protect that compromised individual,” said Hagmann.
If a person becomes so sick that they refuse food and water, Hagmann said it might be time to see a doctor.
How can you prevent it?
Good handwashing is key, especially since alcohol-based hand sanitizer doesn’t work well against the virus.
Hagmann also recommends disinfecting shared spaces with a chlorine bleach solution.
“It’s likely to survive in the environment unless you’re very careful to clean with bleach, because it’s very hearty, the virus,” said Hagmann.