Rotavirus cases in children are rising – but a highly effective vaccine has slashed hospitalizations from the virus by 80% in 2 decades

that spreads easily and can make babies and young children very sick. This year, doctors have been than usual.

Data from the Centers for Disease Control and Prevention shows that almost people tested for rotavirus have the virus. This is only a little higher than last year at this time, when about were positive. However, because rotavirus cases started rising earlier than usual – in January – which means more children are getting sick over a longer period of time.

Often referred to as a stomach flu or stomach bug, rotavirus infection can cause extreme diarrhea, leading to severe dehydration and hospitalization. , infectious diseases that are also on the rise, rotavirus can be prevented with a . But vaccination rates in the U.S. have .

The Conversation asked to explain why this virus is on the rise and what families can do to protect themselves from the illness.

What is rotavirus and why is it dangerous?

Rotavirus, , affects the gastrointestinal system – that is, the stomach and the intestines.

, often when germs from poop get on hands or surfaces and then into the mouth. But a person can also become infected by touching a contaminated surface and then touching their mouth, or by drinking or eating contaminated food or water.

Rotavirus causes that can cause rapid dehydration, which can lead to death if left untreated. There is no medicine to cure the virus. Doctors can only help by giving fluids and watching closely for dehydration. Babies who lose too much fluid may need care in the hospital.

Rotavirus most often . Without vaccination, nearly all children have a rotavirus infection .

The virus causes most instances of and is the in children under 5. Older children and adults typically experience more mild infections, but the virus can cause severe illness in people with weakened immune systems and those over 65.

A safe and effective vaccine

Safe and effective vaccines against rotavirus have been .

U.S. regulators approved , but it was taken off the market the next year after doctors learned that, in very rare cases, it could . The rotavirus vaccines used today are different. Studies in show that these vaccines are safe and work well.

Before vaccines were introduced, rotavirus accounted for more than , including 200,000 emergency room visits, 70,000 hospitalizations and 20-60 deaths in the U.S. each year.

Annually, vaccination prevents an of infants in America. Since 2006, and emergency room visits by 57%.

Recent rotavirus surge

Rotavirus is a springtime illness in America. Cases usually increase over the winter and reach their , then drop off as the weather gets warmer in the summer.

Since January 2026, doctors have been seeing more rotavirus in babies and young children than usual. According to CDC data, about in January were positive, when normally only about 1% of tests are positive. That rate is now peaking at .

Scientists have also found more rotavirus by monitoring to track how germs are spreading. The levels of virus in sewage have since February. Together, this tells doctors that rotavirus is spreading more widely and lasting longer than it usually does, which is why they are watching it closely.

Rotavirus vaccine rates in the U.S. have been declining – received the full vaccine series by 8 months of age in 2018 compared to in 2024. That leaves more infants susceptible to infection. Rotavirus surges are generally shorter in areas where , meaning they could last longer in areas with lower vaccination coverage.

In January 2026, the Department of Health and Human Services from a universal recommendation to a . Although this change was , this has left public health officials increasingly concerned that rotavirus vaccination rates could continue to decline.

Preventing rotavirus infection

Proper hand-washing can help reduce rotavirus transmission, but because rotavirus is highly contagious, preventing the disease through vaccination is the most effective form of protection.

There are available for infants in the U.S. The first dose must be given before 15 weeks of age, and all doses must be completed by 8 months of age.

Rotavirus vaccines reduce the risk of severe disease in infants . This means fewer hospital visits, less risk of dehydration and more babies staying healthy at home.

But these benefits last only when most babies get vaccinated. When vaccination rates drop, rotavirus can spread more easily, and more infants, especially the youngest ones, can get seriously ill. Keeping vaccination rates high helps protect individual babies and keeps the whole community safer.