Mark Gurarie is a freelance writer, editor, and adjunct lecturer of writing composition at George Washington University.

Ronald Lubelchek, MD, is a board-certified infectious disease specialist in Chicago, Illinois. He previously served as the Medical Director for Cook County’s ambulatory HIV clinic, one of the largest HIV clinics in the U.S.

Rotavirus and norovirus infections are common causes of stomach flu, clinically referred to as viral gastroenteritis . This inflammation of the gastrointestinal tract causes diarrhea, nausea and vomiting, abdominal pain, and sometimes fever. Even though both infections cause these symptoms, there are critical differences between the two viruses.

Whereas norovirus is the most common source of infections in adults and people of all ages, rotavirus is more common among children and infants under age 5.

This article breaks down the differences between these viruses, as well as when to contact your healthcare provider, the treatments available, and how to prevent infection.       

Since both rotavirus and norovirus lead to viral gastroenteritis, the symptoms largely align. Both conditions cause:

However, there are some key differences in the ways that norovirus and rotavirus present, including:

While most cases of viral gastroenteritis aren’t themselves dangerous or fatal, they can cause dehydration, which can be a potential complication of both rotavirus and norovirus. The symptoms include:

Both norovirus and rotavirus are easily passed from person to person, and they have similar means of transmission. In terms of causes, however, there are a few key differences.

There are several types of norovirus, with humans contracting three types—G1, G2, and G4—that can be divided into over 25 subtypes. This virus is among the most contagious worldwide, leading to approximately 21 million cases of stomach flu, which is about 60% of those cases.

Noroviruses are spread by the fecal-oral route—when viruses shed in the feces are somehow ingested through the mouth. This occurs due to contact with an infected person or surface, or via contaminated food, drinks, or water. Additionally, droplets of norovirus arising from vomit can also be inhaled, leading to infection.

People are most contagious with norovirus when symptoms arise and about three days after they’ve subsided. Some are contagious for up to two weeks after recovery.

The word "rotavirus" comes from the Latin "rota," meaning "wheel," because of this virus’s characteristic circular appearance. Like norovirus, rotaviruses are transmitted via the fecal-oral route. This means through direct contact, touching contaminated surfaces, or consuming affected water or food can all cause infection.    

Generally affecting those under age 5—though adults can also be infected—rotavirus outbreaks can occur in daycare facilities, schools, at home, or in other areas where many people are in close quarters. As such, cases increase during colder months. Unlike norovirus, people may become contagious before the onset of symptoms, and up to 2 weeks afterward.

When you have stomach flu, the goal of diagnosis is to determine whether norovirus, rotavirus, or another infection is causing symptoms. As such, diagnostic approaches for these viruses largely line up. Here’s a quick breakdown.

At your medical appointment, the healthcare provider will ask about what symptoms you’re having, how long you’ve had them, as well as whether you’ve been traveling or in contact with others who may be sick. They’ll also want to know about your medical history and any medications you’re taking.

Tests of breathing function, heart rate, and blood pressure help providers detect signs of dehydration associated with infection. In some cases, providers use a stethoscope to listen to the abdomen or tap it to check for pain. A digital rectal exam may be needed if there’s blood in the stool (feces).

In most cases, physical exams and medical history are enough for diagnosis, though providers may call for testing to confirm the cause of symptoms. You’ll be asked to leave a stool sample in a special container and send it off for laboratory analysis. Using genetic tests, clinicians detect signs of rotavirus or norovirus. These may include:

Generally speaking, most cases of both norovirus and rotavirus resolve on their own, without the need for medical attention. Largely the treatments of these conditions are identical, and there are no specific medications that directly treat rotavirus and norovirus. The typical approaches to care include:

To help prevent the spread of rotavirus, vaccines like RotaTeq or RotaTrix prevent infants and children from developing severe symptoms in 90% of cases, with 70% experiencing little to no signs of illness. These vaccines take multiple doses, and are given to infants, typically at 2, 4, and 6 months.

Learn More: 2-Month Vaccines: What You Should Know

If you or your child have any of the symptoms of dehydration, you should seek medical care as soon as possible. Get help if you experience dry mouth, loss of energy, lack of urination or tears, reduced skin elasticity, and dizziness. Furthermore, call your provider if infants or young children have stomach flu, if you’re older than 65, or have compromised immunity.

Since both rotavirus and norovirus are transmitted via the fecal-oral route, the core of prevention is good hygiene. This means:

If you or your child is feeling sick, take extra steps to prevent spreading your norovirus or rotavirus infection to others. Stay home from work, keep kids home from school, preschool, or daycare, and be extra mindful about hygiene and sanitation.

Rotavirus and norovirus are the two of the most common causes of viral gastroenteritis, commonly known as stomach flu. These infections, which usually resolve on their own, cause inflammation of the intestinal tract, leading to watery diarrhea, nausea, vomiting, and sometimes fever. Dehydration, a serious medical issue, can also arise.

Rotavirus primarily affects children under 5 and has a slower onset, taking up to two days after exposure. Generally, symptoms last up to eight days, and you’re contagious before they set on. In turn, norovirus affects people of all ages, sets on within 12 to 48 hours, and typically resolves within a couple of days. Infected people can transmit the disease only after symptoms set on, though you may still be contagious for up to two weeks after they’ve resolved.

Primarily, assessment of symptoms is enough for diagnosis, though tests of stool samples or vomit can confirm the underlying cause. These include PCR, immunoassays, or multiplex gastrointestinal assays. Treatment strategies for these viruses line up and focus on rest, rehydration, and managing symptoms. Over-the-counter medications, such as Imodium, Pepto-Bismol, and probiotics can also help with symptoms. Prevention of this condition primarily involves extra effort in handwashing, cleaning surfaces, and safe food handling.      

The good news when it comes to both norovirus and rotavirus is that these illnesses usually resolve on their own. Staying hydrated and getting rest is usually sufficient for taking on the symptoms of infection. However, as with all aspects of health, vigilance is key, and it’s important to know when it’s time to get help. If you’re concerned about your or your child’s stomach flu symptoms, call your provider or get emergency medical attention.

Gas pain? Stool issues? Sign up for the best tips to take care of your stomach.

Thank you, {{form.email}}, for signing up.

There was an error. Please try again.

National Institutes of Health. Viral gastroenteritis (“stomach flu”).

Centers for Disease Control and Prevention. Rotavirus clinical information.

Centers for Disease Control and Prevention. About norovirus.

Centers for Disease Control and Prevention. Norovirus in healthcare facilities fact sheet. Division of Health Care Quality and Promotion.

National Institutes of Health. Symptoms & causes of viral gastroenteritis (“stomach flu”). National Institute of Diabetes and Digestive and Kidney Diseases.

Chhabra P, Gregoricus N, Weinberg G et al. Comparison of three multiplex gastrointestinal platforms for the detection of gastroenteritis viruses. J Clin Virol. 2017;95:66-71. doi:10.1016/j.jcv.2017.08.012

Centers for Disease Control and Prevention. Rotavirus vaccination.

Centers for Disease Control and Prevention. Preventing norovirus outbreaks. CDC VitalSigns.

Centers for Disease Control and Prevention. Norovirus in healthcare facilities fact sheet. Division of Health Care Quality and Promotion.

Centers for Disease Control and Prevention. Rotavirus clinical information.

National Institutes of Health. Viral gastroenteritis (“stomach flu”).

Thank you, {{form.email}}, for signing up.

There was an error. Please try again.

By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.