(WASHINGTON) — Cases of norovirus are rising across the United States, doubling over the last few months, according to updated data from the Centers for Disease Control and Prevention (CDC).
Nearly 14% of tests came back positive for norovirus during the most recent week ending Nov. 15, compared to roughly 7% about three months ago.
Test positivity is a metric used to identify how many people are confirmed to have norovirus after an illness is suspected.
Health experts have said that, like other measurements, test positivity is imperfect as it depends on the number of tests that are ordered, which can vary.
Last December saw a record-breaking rate of norovirus cases in the U.S. with nearly 25% of tests coming back positive. Cases had been trending down since then but have begun to rise in recent weeks, CDC data shows.
Electronic health records data from Epic Research show that Alabama, Nebraska, Oklahoma, Texas and Wyoming are some of the states currently experiencing the highest number of norovirus cases. Emergency department visits have been on the rise since July, Epic Research data shows.
Norovirus is a highly contagious virus that is the most common cause of viral gastroenteritis, which is an inflammation of the inside lining of the gastrointestinal tract.
Although it’s often referred to as the “stomach bug” or “stomach flu,” norovirus illness is not related to influenza.
Norovirus is the leading cause of foodborne illness in the U.S., causing 58% of foodborne illnesses each year, and responsible for about 2,5000 outbreaks annually, according to the CDC.
The most common symptoms are nausea, vomiting, stomach pain and diarrhea. Patients, however, can also experience fever, headaches and body aches.
Typically, an infected person will develop symptoms between 12 to 48 hours after being infected. However, norovirus typically resolves quickly and, in most healthy adults, lasts one to three days, according to the CDC.
Health experts say the best way to prevent getting norovirus is to wash hands with warm soap and water for 20 seconds. Hand sanitizer alone does not work well against norovirus.
The CDC says people should wash their hands after using the toilet or changing diapers as well as when eating, preparing or handling food.
Members of the CDC’s Advisory Committee On Immunization Practices at the Center for Disease Control (CDC) headquarters in Atlanta, Georgia, US, on Friday, Dec. 5, 2025. (Megan Varner/Bloomberg via Getty Images)
(NEW YORK) — The Centers for Disease Control and Prevention (CDC) announced on Monday it is changing the childhood immunization schedule.
The federal health agency is removing the universal recommendation for multiple shots, in what it calls an attempt to mirror the schedules of peer countries.
Instead of being universally recommended for almost all children at certain age cut offs, vaccines are now split into three categories: vaccines for all children, vaccines for certain high-risk groups and vaccines based on shared clinical decision making.
Shared clinical decision making is the term used by CDC to imply that patients, and parents, should talk to their provider about whether they should be vaccinated.
Some of the vaccines and immunizations that are no longer universally recommended include RSV, flu and COVID, as well as the hepatitis and meningococcal vaccines.
For children not in certain high-risk groups, no vaccine is recommended before the age of two months.
The change comes after President Donald Trump signed a memo in early December last year directing Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. to examine how other nations structure their childhood vaccine schedules.
HHS officials say the change will not affect health insurance coverage of vaccines.
“President Trump directed us to examine how other developed nations protect their children and to take action if they are doing better,” Kennedy said in a statement. “After an exhaustive review of the evidence, we are aligning the U.S. childhood vaccine schedule with international consensus while strengthening transparency and informed consent. This decision protects children, respects families, and rebuilds trust in public health.”
The changes drew rebuke from doctors, who expressed concern that such a change did not undergo further debate before being implemented.
The CDC’s vaccine advisory committee met last month to discuss the childhood vaccine schedule, but only voted to remove the universal recommendation for the hepatitis B vaccine at birth.
“I thought there might be proposals that were debated amongst experts in a public meeting, and then maybe something like this resulting from that, but not in the way this has been done, where a new schedule is released, which has already been signed on to by all the health advisors for the president,” Dr. Dave Margolius, an internal medicine physician and director of public for the city of Cleveland, told ABC News.
Dr. Demetre Daskalakis, former director of the CDC’s National Center for Immunization and Respiratory Diseases, said altering the schedule without consulting U.S. experts in pediatrics, infectious diseases and public health “undermines both scientific rigor and transparency.”
He told ABC News that the American health care system is unique, which makes it difficult to align the U.S. vaccine schedule to those of peer nations.
“Vaccine schedules should be crafted to reflect the specific patterns of disease and access to healthcare in the United States; unfortunately, these vital factors were not adequately considered in the development of the new schedule,” Daskalakis said.
In a press briefing representing the American Academy of Pediatrics (AAP), Dr. Sean O’Leary, an infectious disease physician and chair of the AAP Committee on Infectious Diseases, said the federal government can no longer be trusted in its role to protect American children from vaccine-preventable diseases.
“Tragically, our federal government can no longer be trusted in this role,” O’Leary said. “Unfortunately, our government is making it much harder for pediatricians to do our jobs, and they’re making it much harder for parents to know what to do.”
O’Leary confirmed the AAP was not consulted by HHS ahead of this decision to change the vaccine schedule.
Additionally, Sen. Bill Cassidy (R-La.), a physician and chair of the Senate’s health committee, distanced himself from the CDC’s decision to change the childhood vaccine schedule.
“Changing the pediatric vaccine schedule based on no scientific input on safety risks and little transparency will cause unnecessary fear for patients and doctors, and will make America sicker,” Cassidy wrote in a post on X, rejecting the recent changes.
Cassidy added that the schedule is “not a mandate,” but rather a recommendation that gives parents the “power” to choose which vaccines their children receive.
Catherine Stein, far right, speaks during a meeting of the CDC’s Advisory Committee on Immunization Practices on September 18, 2025 in Chamblee, Georgia. (Elijah Nouvelage/Getty Images)
(NEW YORK) — The Centers for Disease Control and Prevention’s vaccine advisory committee is set to meet Thursday and Friday to discuss the childhood vaccine schedule, adjuvants and contaminants, and the hepatitis B vaccine.
It marks the third meeting this year of the Advisory Committee on Immunization Practices (ACIP) since Health and Human Services Secretary Robert F. Kennedy Jr. fired all 17 members, replacing them with his own hand-selected picks, many of whom have expressed vaccine-skeptic views.
This is also the first meeting since the chair of the ACIP, Martin Kulldorff — a former Harvard Medical School professor — accepted a permanent role at HHS. Pediatric cardiologist and former U.S. Air Force flight surgeon Dr. Kirk Milhoan will chair the committee during the upcoming meeting.
Milhoan is a fellow with the Independent Medical Alliance, a group that has advocated for unproven treatments for COVID-19, including hydroxychloroquine and ivermectin.
A draft agenda posted online indicates the ACIP will discuss and vote on recommendations around the hepatitis B vaccine on day one and discuss the childhood vaccine schedule on day two.
“I think every single thing on that agenda is concerning,” Dr. Richard Besser, resident and CEO of the Robert Wood Johnson Foundation and acting director of the CDC during the administration of former President Barack Obama, told ABC News. “We have an administration [that] seems hellbent on undermining people’s trust in vaccination.”
Hepatitis B vaccine
Since the new ACIP members were installed, the committee has recommended against flu vaccines containing the preservative thimerosal — despite public health experts saying there is no evidence that low doses of thimerosal in vaccines cause harm — and has narrowed existing recommendations for the combined MMRV shot that protects against measles, mumps, rubella and chickenpox.
The first day of the meeting will include presentations and discussions about the hepatitis B vaccine.
The agenda also lists a scheduled vote and, although it’s not clear what will be voted on, experts believe the universal hepatitis B vaccine dose given at birth will be at issue.
The CDC currently recommends that the first dose of the three-dose hepatitis B vaccine be given to babies within 24 hours of birth. Doctors have said the universal birth dose recommendation has virtually eliminated hepatitis B among babies in the U.S.
However, earlier this year, Kulldorff questioned whether it was “wise” to administer shots “to every newborn before leaving the hospital.” Separately, Kennedy has falsely linked the hepatitis B vaccine to autism.
Some experts believe the panel will vote to either delay or remove the decades-long recommendation that newborns be vaccinated against hepatitis B.
“I am concerned that the committee is going to attempt to minimize the harm resulting from any changes to this long-standing recommendation,” Dr. Fiona Havers, a former CDC official who worked on vaccine policy and led the CDC’s tracking of hospitalizations from COVID-19 and RSV, told ABC News.
“They’re going to say that there’s no need to vaccinate babies at birth because you can screen mothers and only vaccinate babies born to patients who test positive or whose status is unknown,” she continued.
Havers said only vaccinating high-risk babies was the policy in the U.S. before the universal birth dose was implemented, but it was changed after doctors saw that babies and children continued to be infected with hepatitis B.
Additionally, babies infected with hepatitis B are at risk for chronic infection as well as liver disease, liver failure and even liver cancer.
“Babies can be infected not only by their mother if she has hepatitis B, but also by caregivers or others in the community who may not know that they have hepatitis B and any change to the routine recommendation means that we will see an increase in hepatitis B infections in infants and children,” Havers said.
She added, “Any hepatitis B infections that occur because a child wasn’t vaccinated at birth are an avoidable tragedy. We will start seeing more children living with a lifelong incurable infection that can lead to death from cirrhosis or liver cancer.”
Childhood immunization schedule
Besser said he is particularly concerned about the second day, which includes a discussion about the childhood immunization schedule.
The draft agenda is scant on details aside from topics including CDC vaccine risk monitoring evaluation discussion, vaccine schedule history, vaccine schedule considerations and a discussion of the childhood/adolescent immunization schedule
Earlier this year, the ACIP formed two new work groups, one focusing on the cumulative effects of children and adolescents receiving all recommended vaccines on the schedule and another reviewing vaccines that haven’t been examined for more than seven years.
Kennedy has suggested that children receive too many vaccine doses “to be fully compliant” and that the number of doses children receive has increased from three doses during his childhood to 92 doses today.
Doctors previously told ABC News that children actually receive about 30 vaccine doses and that the number of available, recommended immunizations has grown since the first vaccines were recommended in the late 1940s, based on evolving science and manufacturing capacity.
Besser said he has not heard safety concerns about the schedule from vaccine experts, pediatricians, those who administer vaccines or patient advocacy groups.
“There had not been concerns raised around the immunization schedule and forming a group that is going to look at [the schedule] wholesale when the going-in presumption is that it’s not safe really, really worries me,” Besser said.
The panel will also discuss vaccine “adjuvants and contaminants,” according to the draft agenda.
In a 2023 interview on The Joe Rogan Experience, Kennedy claimed aluminum adjuvants are neurotoxins and are associated with allergies, including food allergies.
The CDC says adjuvants are ingredients used in some vaccines to help boost the immune response and have been used safely in vaccines for more than 70 years.
(NEW YORK) — U.S. childhood and teen obesity rates have reached record-highs while adult obesity rates may be slowing, according to two new reports published early Wednesday by the Centers for Disease Control and Prevention (CDC).
Researchers used measured heights and weights from the National Health and Nutrition Examination Survey (NHANES) — run by the CDC’s National Center for Health Statistics — to track trends over more than six decades.
In the first report, the team found that, in the most recent survey conducted between August 2021 and August 2023, 40.3% of adults aged 20 and older were found to be obese, including 9.7% with severe obesity and another 31.7% classified as overweight.
By comparison, for the survey conducted between 1988 and 1994, 22.9% adults aged 20 and older were found to be obese including 2.8% with severe obesity and 33.1% classified as overweight.
However, some of the newest estimates suggest the rapid rise seen in earlier decades may be slowing slightly.
In the 2017-2018 survey, 42.4% of adults were classified as obese, which is the highest figure ever recorded. The decrease between the two most recent surveys could be indicative of a downward trend. Dr. John Brownstein, an epidemiologist and chief innovation officer at Boston Children’s Hospital and an ABC News contributor, noted that it aligns with observations of electronic medical record data.
“So, we’re seeing, for the first time in decades, that there’s like a leveling off and even maybe a slight decrease and I think this is like challenging a major shift from the long-held expectation that obesity would just be climbing year after year,” he said.
According to Brownstein, the decrease is likely due to many factors including public health policies and education about healthier lifestyles as well as medications such as GLP-1s.
It can help produce more insulin, which reduces blood sugar and therefore helps control Type 2 diabetes. It can also interact with the brain and signal a person to feel full, which — when coupled with diet and exercise — can help reduce weight in those who are overweight or obese.
Many GLP-1s have become household names, including Ozempic, Wegovy, Mounjaro, Zepbound and Trulicity.
“I do think the advent of the GLP-1s are absolutely playing a role,” Brownstein said. “At that point in 2023, they weren’t as widespread as they are today. So, we expect that these factors could play even more significant role in more recent times.”
Dr. Justin Ryder, an associate professor of surgery and pediatrics at Northwestern Feinberg School of Medicine, said he’s cautiously optimistic about the slight decrease.
However, he added that it remains to be seen whether this is a blip or if the decrease is indicative of a longer-term trend.
“We’ve seen dips in the past and typically, when they do, in the next reporting period it goes right back up,” Ryder told ABC News. “And that’s because of how the sampling is done. This is a random sample of U.S. adults.”
He noted that the random sampling makes it difficult to draw firm conclusions.
“Could it just be the people who were sampled, or is it real?” he said. “And I think we won’t know that until we have another set or a larger set of data over either the same sampling period or a couple more years from now.”
Meanwhile, a second report found that more than one in five U.S. children and teenagers have obesity, which is the highest figure ever recorded.
The survey conducted between August 2021 and August 2023 found 21.1% of U.S. children and teenagers between ages 2 and 19 have obesity, up from 5.2% during the 1971-1974 survey.
Additionally, 7% of children live with severe obesity, an increase from the 1% seen 50 years ago, according to the report.
“This is exceptionally concerning,” Dr. David Ludwig, co-director of the New Balance Foundation Obesity Prevention Center at Boston Children’s Hospital and professor of nutrition at Harvard School of Public Health, told ABC News.
He added that in the 1970s, “children were certainly recognized [as obese] but it was the rare child, one in 20. And now we’re looking at one in five children with obesity.”
Ludwig said it had seemed for a short period of time that the prevalence of obesity was decreasing at least among 2-to-5-year-olds when rates declined from 12.1% in 2009-2010 to 9.4% in 2013-2014.
At the time, he viewed it as a “glimmer of hope” — but rates increased again and now sit at 14.9% for this age group.
“We saw that dip and we all got excited thinking that we were beginning to turn the tide,” Ludwig said. “In retrospect, that was more of a statistical aberration, more of mirage than a true glimmer of hope because the trend overall has continued upward.”
To reverse the trends among children, Ryder said the 2-to-5-year-old group will need lifestyle modifications such as healthier eating. The 6-to-11-year-old group will need similar methods although some medications are available, he said.
For children above age 12, Ryder said medications and bariatric surgery are options.
Nearly 23% of children ages 12 to 19 were considered obese in the most recent survey. Ryder said that means they meet the guidelines for intensive treatment, whether that’s lifestyle adjustments or in combination with medications or surgery.
“I think the only way that we’re going to see a downward trend in that number is if we take that adolescent group of 12- to 19-year-olds and actually start to apply the clinical practice guidelines and treat those kids seriously, offering them medications,” he said.
Ishani D. Premaratne, MD, is an integrated plastic & reconstructive surgery resident and member of the ABC News Medical Unit.
