Rotavirus and norovirus are two common viruses responsible for acute gastroenteritis, an illness often referred to as “stomach flu.” While both cause similar unpleasant symptoms, they have distinct characteristics and impacts on different populations. Understanding their differences is helpful for prevention and management.
Rotavirus: Symptoms and Spread
Rotavirus infection causes symptoms like severe watery diarrhea, vomiting, fever, and abdominal pain. These symptoms usually begin about two days after exposure and can last for three to eight days. Rotavirus primarily affects infants and young children, and was historically a leading cause of severe diarrheal disease in this age group. Adults can contract rotavirus, but their symptoms are usually milder or absent.
The virus spreads easily through the fecal-oral route, via direct contact or contaminated objects, food, or water. Rotavirus is highly resilient and can survive on surfaces for weeks or months, contributing to its spread. A significant preventive measure against rotavirus is vaccination. Two oral vaccines, Rotarix and RotaTeq, have been available since 2006 and have substantially reduced cases and hospitalizations in children under five.
Norovirus: Symptoms and Spread
Norovirus causes a sudden onset of symptoms like vomiting, watery diarrhea, nausea, and stomach cramps. Other symptoms can include fever, headache, chills, and body aches. Norovirus affects all ages, and symptoms appear 12 to 48 hours after exposure. The illness resolves within one to three days.
Norovirus is highly contagious, spreading easily through the fecal-oral route, contaminated food, water, or surfaces. It often causes widespread outbreaks in settings like healthcare facilities, cruise ships, schools, and nursing homes, due to its low infectious dose and persistence on surfaces. Unlike rotavirus, there is no vaccine available for norovirus.
Comparing the Impact of Each
Rotavirus and norovirus differ in severity, duration, and vulnerable populations. Before widespread vaccination, rotavirus caused more severe dehydration, hospitalizations, and deaths, particularly in unvaccinated infants and young children. The rotavirus vaccine has significantly reduced these severe outcomes, cutting hospitalizations in children under five by 45-94%. While rotavirus symptoms can last up to eight days, norovirus symptoms are shorter, lasting one to three days.
Norovirus often leads to more widespread and rapid-onset outbreaks affecting all ages, including healthy adults. Its highly contagious nature, with a very low infectious dose, allows it to spread quickly through communities. Although norovirus illness is usually self-limiting, it can lead to severe dehydration, especially in young children, older adults, and immunocompromised individuals, sometimes requiring emergency room visits. The absence of a vaccine for norovirus means it remains a public health challenge, causing millions of cases annually.
Protecting Yourself and Others
Preventing the spread of both rotavirus and norovirus relies on consistent hygiene. Thorough handwashing with soap and water is important, especially after using the bathroom, changing diapers, and before eating or preparing food. Alcohol-based hand sanitizers are less effective against norovirus, making soap and water the preferred method.
Proper cleaning and disinfection of contaminated surfaces is also important. For norovirus, a bleach-based cleaner (5 to 25 tablespoons of household bleach per gallon of water) is recommended, as the virus can survive on surfaces for days or weeks. Isolating sick individuals and avoiding sharing food, utensils, or close contact helps prevent further transmission. Recognizing signs of dehydration, such as decreased urination, dry mouth, dizziness, or crying without tears, is key. If signs are severe or symptoms do not improve, seek medical attention.