Will norovirus surge early again this year? Here's what scientists say
Will the upcoming norovirus season be just as early and active as the past year?
While the answer may be anyone's guess right now, federal health officials recently warned that the dominant strain of the contagious virus — the leading cause of vomiting, diarrhea, and foodborne illness in the U.S. — has changed between the 2022-2023 and 2024-2025 seasons.
'GII.17 has caused 75 percent of all norovirus outbreaks during the 2024–25 season so far, thereby replacing GII.4 as the predominant norovirus outbreak strain in the United States,' Centers for Disease Control researchers wrote in an article published this month by the agency's Emerging Infectious Diseases journal.
This past season also started at the earlier date of October, as opposed to December. GII.17 also drove a record wave of outbreaks.
But, what all of this might mean going forward needs further research.
'Additional sequence analysis of complete GII.17 genomes and identification of cross-protective neutralizing antibodies of GII.17 compared with GII.4 viruses could help clarify whether GII.17 viruses will persist. Continued surveillance is needed to determine if this genotype remains the dominant genotype, as well as whether the norovirus season continues to start earlier than previous years,' they wrote.
A spokesperson for the agency told CBS News that there are 'currently insufficient historic data to predict whether norovirus GII.17 will remain the dominant genotype and lead to an earlier onset of the norovirus season later this year.'
They pointed to a surge of GII.17 strains in Asia and Europe in 2014 that was followed by no reports of a change to seasonality, and noted that there has been no clear evidence to prove that GII.17's emergence was the cause of a change to the norovirus season last year.
Still, this past season reached the worst levels in a decade. There were 91 suspected or confirmed outbreaks during the first week of December, which Yale Medicine said exceeded the number of outbreaks during the same week in any year since 2012. The majority were the GII.7 strain. In years when there is a new strain of the virus, there can be 50 percent more norovirus illness.
Cases continued to tick up months into this year. By May 7, there were 2,571 outbreaks. During the same time last year, there were only 1,358.
'The total number of outbreaks reported during the 2024 to 2025 seasonal year is above the range reported during the same period during the 2012 to 2020 and 2021 to 2024 seasonal years,' the CDC said.
Cases have fallen markedly since January, and are now at low levels. While the outbreaks occur throughout the year, they are the most common from November to April as people head indoors and it's easier to spread norovirus through infected particles. Anyone who consumes raw shellfish is also at risk of contracting it.
Infection can be deadly largely among adults aged 65 and up, but anyone can get sick. Children younger than 5 years old and people with weakened immune systems are more likely to develop severe infections. There are 900 deaths on average each year and between 19 and 21 million illnesses. There's no specific treatment for norovirus, but most people recover with a period of up to three days.
'The norovirus can spread so quickly, but also, as we already talked about, norovirus can be very — it's usually very fast. So yeah, if people are taking care of themselves, we leave them alone,' explained Dr. Joanna Bisgrove, a family physician at Rush University Medical Center. 'But if it keeps going, we're like, maybe this isn't norovirus, and we need to do other things.'
Hashtags

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles


New York Post
6 hours ago
- New York Post
Hungry bear breaks into nursing home, gets walloped with walker before being lured out with Rice Krispies treats
His stomach was growling for geezers! A hungry black bear broke into a Pittsburgh-area nursing home and wreaked havoc — forcing a caretaker to whack him with a walker while others coaxed him with Rice Krispies treats, workers said Friday. 'I grabbed a walker and was hitting him, trying to get him away from the residents,' nursing assistant Charlene Elliot told CBS News. Advertisement A young black bear broke into St. Andrew's Village, a nursing home located in Indiana, Pennsylvania, leading a caretaker to whack the animal before other members of the building coaxed him with Rice Krispies treats. WPXI-TV News Pittsburgh '[I thought] he's going to maul them or swipe, slap at them. That was my worst fear.' The ballsy young bruin smashed through a window at St. Andrew's Village in Indiana, Pennsylvania, at 11 p.m. Tuesday, and made a b-line for an elderly resident's bed, Elliott said. Advertisement 'I was sitting there at our nurse's station and I heard a big crash,' Elliott told Channel 11. 'Going through my mind was, 'Get the thing out of here!'' The un-bear-able burglar high-tailed it down a hallway into several bedrooms — at one point coming nearly nose-to-nose with an elderly resident, Elliott told the station. 'He could have mauled him. I mean, one swipe,' Elliott said. Advertisement The bear made its way into the nursing home at around 11 p.m. Tuesday and made a b-line for a resident's bed, said nursing assistant Charlene Elliot. WPXI-TV News Pittsburgh 'I told them all to shut the doors. Get the doors all shut!' Meanwhile, another resident offered the critter a sandwich in an attempt to lure him out of the building. 'She's like 'Well, go ahead and give it my sandwich!' and I'm like, 'No, we can't do that!' Elliott said. Advertisement Staffers eventually succeeded at shooing the animal out of the center using the lure of Rice Krispies treats, she said. All told, the 150-pound bear was inside the retirement home for about 15 minutes and nobody was injured. Wildlife officials later captured the bear using a trap, set up with donuts, Thursday morning. 'We are incredibly proud of our team's quick thinking and dedication to ensuring the safety of everyone in our community,' Presbyterian Senior Living, which runs the home, said in a press release.
Yahoo
11 hours ago
- Yahoo
Afghanistan's foremost OB-GYN says the country is in a maternal health crisis
Kabul — Dr. Najmussama Shefajo is probably Afghanistan's best known and most experienced OB-GYN. She became a household name from her regular appearances on Afghan television, where she talked openly about women's reproductive health, a subject still considered taboo in Afghanistan. Over the past decade, CBS News has made several visits to her private clinic in central Kabul, but it has never looked as busy as it does now. Her clinic was flooded with new patients after the Taliban banned women from nursing and midwife training courses back in December. It's a move that has started to take its toll on Shefajo, who told CBS News she has been suffering from migraines for quite some time "because of the tension." "I see my patients are very poor, they cannot pay, I cannot help them, and all the pressure comes on me and I get a headache," Shefajo said. Still, Shefajo has remained a committed teacher. She found a way to get around the Taliban's education ban for her student nurses and midwives by giving them all jobs at her clinic. This means they are technically no longer students, but employees, even as she continues to train them. She says that if the current policies remain in place though, the situation in Afghanistan will worsen. "The previous doctors, midwives, nurses are getting older and older and they will die," Shefajo said. "Who will provide services?" Following the U.S. withdrawal and immediately after taking power in 2021, the Taliban also banned girls over the age of 12 from attending school. But the results of such a health care shortage could be catastrophic, Shefajo believes. Under Taliban rule, women and girls can only be treated by female doctors. Male doctors can only treat women when a male guardian is present. "For sure the number of deaths will be increasing, and one day there will not be female in Afghanistan," Shefajo said. An Afghanistan without women — the Taliban insists that is not what its policies are aimed at. In the courtyard outside her clinic, CBS News tried to ask some of the husbands, fathers and guardians what they thought about the Taliban's ban on maternal health education for women, but no one wanted to talk. Shefajo said her message to the Taliban is to rescind the policy on women's health education. "As a doctor, as a mother, as a woman, as a Muslim, I request them…to give a chance for the female to help you to build the country." Musk alleges Trump's name appeared in Epstein files as feud escalates What to know about President Trump's travel ban on nationals from 12 countries Trump says he's disappointed by Musk criticism of budget bill, Musk says he got Trump elected


Boston Globe
11 hours ago
- Boston Globe
Bad Botox? Six cases of botulism on the South Shore tied to possible Botox injections
South Shore Health declined to answer questions about whether they were treating suspected cases or how many they were seeing, referring instead to the Department of Public Health. Advertisement However Jason Tracy, chief medical officer at the hospital, said generally that patients are given a presumptive diagnosis made off of their clinical presentation of symptoms and history of recent injections. Related : From there, the hospital would involve both the Department of Public Health and the Centers for Disease Control, which has an anti-toxin that it provides on a case-by-case basis. The anti-toxin helps slow the progression of symptoms, but does not reverse them, and so hospitals typically also provide supportive measures. 'This is quite rare,' Tracy said. 'This is different than a food-borne botulism type case. It's not as though there is a lot body of literature to refer clinicians to to give prognosis and historical elements and time courses for what to expect.' South Shore Hospital in Weymouth. Pat Greenhouse/Globe Staff Use of botulinum toxin — commonly known by the popular brand name Botox — for cosmetic procedures is widely Advertisement Cosmetic treatments with botulinum toxin use doses much lower than for medical treatments, said Dr. Mathew M. Avram, director of the Mass General Hospital Dermatology Laser and Cosmetic Center.. With regulated, FDA-approved products in a healthy adult, the amount of the toxin is so small that it is exceedingly rare for it to cause botulism. 'I've never seen a patient or had a colleague of mine at Mass General or elsewhere that has told me they have had a case of this. It is not something that happens normally,' Avram said. 'Someone would have to go outside the realm of what you would typically inject to encounter these issues, for a typical patient.' Beyond injecting far too much, poor administration technique or using counterfeit products can increase risks. 'We have seen instances where injectors have used counterfeit products or products they developed on their own,' Avram said. 'These are unsafe practices that can harm patients.' According to the advisory, botulism results when the botulinum toxin circulates in the blood. Symptoms including double or blurred vision, drooping eyelids, slurred speech, difficulty swallowing, and difficulty breathing. Such symptoms are sometimes followed by muscle weaknesses, which can progress over the course of hours or days. Advertisement DPH has asked clinicians to warn patients interested in these cosmetic injections of the potential risks, and is advising patients to receive injections only from licensed providers. 'If someone has had a botox injection and has had those symptoms they should seek medical attention,' Tracy said. 'I don't want to create worry but someone having visual changes, slurred speech and difficulty swallowing — they should not ignore it." The reports are only the latest Botox problems to surface in the South Shore. In November, 38-year-old Rebecca Fadanelli, was arrested and charged for selling counterfeit Botox out of Skin Beauté Med Spa in Easton and Randolph. Jessica Bartlett can be reached at