How does rotavirus cause diarrhea?

Diarrhea is the second leading killer disease of children less than five years old around the world. Diarrheal disease is caused by infection with various bacterial, viral, and parasitic organisms. There are six pathogens that are responsible for the majority of childhood diarrhea: Shigella, rotavirus, adenovirus, enterotoxigenic E. coli, Cryptosporidium, and Campylobacter.

What is rotavirus? Rotavirus is the deadliest cause of diarrheal disease among children. It was discovered by a virologist named Dr. Ruth Bishop in 1973 while she was studying biopsies from children with gastroenteritis. When viewed through a microscope, rotavirus is shaped like a wheel – which is why it was named “rotavirus.”  

How is rotavirus transmitted? The primary mode of transmission is through the fecal-oral route. The virus enters the body through the mouth, often by direct contact between people or with feces-contaminated water. Risk of rotavirus transmission is increased when there is limited access to clean water, sanitation, and hygiene (WASH).   

Why is rotavirus infection so pervasive? Rotavirus is highly resilient and can survive for weeks or months on surfaces or objects. Additionally, rotavirus is highly contagious and easily transmittable as very few rotavirus virions (the infective form of a virus) are needed to cause infection.

How does rotavirus cause diarrhea? Once rotavirus enters the body, it travels to the small intestine where it replicates. This can make it difficult for the intestine to absorb sodium, glucose, and water. The effects of this vary, as some children may have little or no symptoms while others may suffer from severely dehydrating diarrhea. Rotavirus infection can also cause fever and vomiting. The incubation period—the amount of time between exposure and appearance of first symptoms—for rotavirus diarrhea is short, usually less than 48 hours.

How is diarrhea caused by rotavirus treated? There is no specific medicine to treat rotavirus infection because the virus does not respond to antibiotics or other drugs. Oral rehydration therapy (ORT) is a cornerstone treatment for replacing lost fluids; in severe cases, health workers use intravenous fluids. Additionally, zinc supplements help replace an essential nutrient that becomes depleted during diarrhea.

Who is impacted most by rotavirus? Many have labeled rotavirus the “democratic” virus because children are exposed in every country across the world. In high-income countries, children who become sick from rotavirus are often able to access emergency IV fluids from a hospital, so fatalities are rare. However, in low-income settings where there is limited access to treatment, diarrheal disease from rotavirus can be deadly.

How is rotavirus prevented? Vaccination is the best–and most reliable–method to prevent rotavirus infection. Rotavirus vaccines, which have been available since 2006, save lives and protect children. To date, more than 120 countries have introduced rotavirus vaccines into their national immunization programs. However, millions of infants worldwide still do not have access to vaccination. We must work together to promote awareness of, access to, and uptake of rotavirus vaccines to prevent illness and save lives!

Learn more about the impact rotavirus vaccines can have around the world.