You wouldn’t imagine it: an unusually high number of Americans are vomiting these days.
Ninety-one norovirus outbreaks were reported to the Centers for Disease Control and Prevention (CDC) during the first week of December (shown in the orange line in the chart below), the last week for which data are available. That’s more than has been reported at this time of year since 2012.
Viral stomach disease, which causes intense but fortunately short episodes of vomiting and diarrhea – with or without a brief period of fever, chills and body aches – normally spreads in winter and recedes in the warmer months . This year’s surge has been fiercer than usual, with more outbreaks breaking out earlier than in pandemic years (indicated by the blue lines) and pre-pandemic years (which fall within the grayed out).
Additionally, as of late December, nearly 23% of people tested positive for norovirus in a sample of clinical laboratories across the country – an extraordinarily high proportion, well above the usual peak of 10 to 15%.
The CDC numbers, while useful for comparing year-to-year trends, are a significant underestimate of the true spread of norovirus, says Lee-Ann Jaykus, a microbiologist at California State University. North Carolina who leads NoroCORE, a food virology collaboration between several federal agencies. “The numbers are really ridiculous,” she says.
Data on the norovirus outbreak comes from a sample of 14 states — not the entire United States — and the agency does not count individual norovirus cases. Many people don’t seek medical attention because of symptoms, and even if they do, norovirus is not an illness that doctors and labs are required to report when they diagnose it.
Experts say they don’t think this trend is simply because more people are seeking care for their symptoms this year. “I think there is an increase in doctor visits and infections, so the increase is real and not just an increase in testing,” wrote Robert Atmar, a norovirus researcher at Baylor College of Medicine, in an e -mail to Vox.
The best way to protect yourself during this season’s norovirus surge is to wash your hands: Norovirus is primarily spread when traces of a sick person’s poop or vomit sneak into our mouths via our hands or food that she prepared. However, the virus also spreads through aerosols left behind after someone vomits, so it’s also good to take precautions if you’re around someone who has contracted the virus.
Why are norovirus levels so high right now?
Norovirus is reaching higher levels than usual since the pandemic. This is probably related to the fact that immunity to the virus only lasts a few years or so. Norovirus levels have plummeted during the pandemic due to more masking, greater social distancing, and more careful hand and surface hygiene – and as people have abandoned these behaviors, protection of the general population against the virus has decreased. This may explain why the United States has experienced more outbreaks in post-pandemic years than in pre-pandemic years.
“My first thought was, ‘Well, do we have a new variant?’ »
But this year’s rise is earlier and higher than trends in recent years. Why is this season so bad?
“My first thought was, ‘Well, do we have a new variant?’ “, explains Jaykus. In recent years, new variants of norovirus have been linked to spikes in infections globally. Although genetic analyzes of circulating noroviruses by the CDC have yet to show dramatic changes this season, the possibility of a new strain is a priority for many experts.
“I can assure you that my colleagues at the CDC are currently doing a lot of sequencing to determine if there is a new strain, but it’s too early to tell,” Jaykus says. (A CDC spokesperson confirmed that reported outbreaks this season have exceeded recent and pre-pandemic numbers.)
How to protect yourself against norovirus or take care of yourself if you are sick
Washing your hands, cleaning surfaces carefully, keeping your distance from people who are seriously ill, and wearing a mask if there is a chance that someone may have recently vomited nearby are the best ways to prevent the spread of this disease. nasty infection.
If you’re infected with this very gnarly bug, take comfort in knowing that it usually disappears almost as quickly as it appears.
Staying hydrated is essential: if you feel nauseous, drink water or an electrolyte drink every 15 to 30 minutes, and if you feel like lying down afterward, sit up to reduce reflux. It is not necessary to drink a liter of liquid at a time; you just want to have enough to produce urine at least every six hours. Wait until you have an appetite to start eating solid foods, and start with bland foods like bananas and dry toast.
Alcohol-based sanitizer doesn’t kill norovirus very well, so clean your hands with soap and water. And clean shared surfaces with a bleach-based product – only a few virus particles are needed to cause an infection, and they can live for weeks on surfaces, so be as thorough as possible.
If you develop bloody diarrhea, can’t keep down enough fluids to produce some urine, or if your symptoms last more than three days, it’s time to see a doctor.
Otherwise, thank your lucky stars it’s over and keep washing your hands: people often shed norovirus for weeks after that first spectacular bathroom moment.
A norovirus vaccine will likely be available within a few years
For healthy people, a norovirus infection results in some truly miserable times in the bathroom, but it’s usually not fatal. However, the virus can put the lives of babies and the elderly at risk, and scientists around the world have been working to develop a vaccine to mitigate the worst effects of the infection.
Several companies are attempting to develop norovirus vaccines using both mRNA vaccine technology and more conventional vaccine development strategies, with varying levels of success. HilleVax stopped work on a vaccine candidate after it was found to be ineffective in a recent trial, Moderna is in the late stages of developing an mRNA vaccine against the virus, and Vaxart is studying several vaccine candidates as of oral pills, which were only moderately effective in alleviating symptoms. .
It hasn’t been an easy road, says Jaykus, who has advised pharmaceutical companies on potential applications of norovirus vaccines. “There are literally hundreds of strains (of norovirus),” she says, and the Food and Drug Administration wants a vaccine that will protect people against most, if not all, of them. Additionally, manufacturers have struggled to create a vaccine whose protection lasts more than a few years.
It will likely be at least three to five years before a norovirus vaccine is available for the smallest segment of the population — likely babies, Jaykus says. After all, young children are not only among the people most affected by serious stomach problems, but they are also the most responsible for spreading the virus to the rest of us. They don’t wash their hands as regularly or thoroughly as adults, and they face each other all the time.
Older adults, particularly those living in nursing homes, would be the second priority due to the severity of illnesses caused by norovirus in this population. The rest of us will have to wait even longer to get a shot that will protect us from the dreaded stomach virus.
