In the United States (U.S.), rotavirus used to be most common during the winter and spring months, but since the introduction of a vaccine, this is less consistent.
Rotavirus can be found infecting the stomach and intestine.
Symptoms take about 2 days to appear after infection.
Profuse watery diarrhea may occur several times in a day. Vomiting and diarrhea can last from 3 to 8 days.
This can lead to dehydration, which can be dangerous.
Signs and symptoms of dehydration include:
- decreased urination
- dry or overly cool skin
- absence of tears when crying
- dry or sticky mouth
- dry throat
- sunken eyes
- sunken fontanel, the soft spot on the head of an infant
- extreme thirst
- feeling dizzy on standing up
A child may be unusually sleepy or fussy.
After one infection, a repeat infection is possible. However, as immunity develops with each infection, subsequent cases are less severe. There may also be different strains of the virus.
Most adults build up immunity during childhood, so they are less susceptible to rotavirus.
However, adults can catch it, especially if they have a compromised immune system, if they are traveling in a place where the virus is common, or if they are exposed to an epidemic. An adult can also catch the virus from a child.
The dehydration that can result from rotavirus can be more serious than the infection itself. It is the most common cause of death in rotavirus cases.
In 2013, the World Health Organization (WHO) estimated that 215,000 children worldwide died due to rotavirus infection, mostly in developing countries.
Causes and risk factors
There are different types of rotavirus, but five main strains are responsible for over 90 percent of rotavirus infections in humans.
Rotavirus is mainly transmitted by the fecal-oral route.
The feces of an infected person can contain more than 10 trillion infectious particles per gram. Only between 10 and 100 particles are needed to transmit infection to another person.
A person can transmit the virus by not practicing good hand hygiene. Not washing the hands before eating or after using the bathroom can spread the virus.
Touching a surface that has been contaminated with rotavirus and then touching the mouth area can result in infection.
Infections frequently occur in places where there is a high concentration of young children, such as nurseries and kindergartens.
The virus can live for several hours on the hands, and for longer on hard surfaces.
Diagnosis and treatment
Rotavirus causes severe diarrhea.
A stool test can detect rotavirus.
In a laboratory, enzyme immunoassay can detect the virus.
Licensed test kits are available that are sensitive, specific and detect all serotypes of rotavirus.
Symptoms normally disappear without treatment.
A doctor should be consulted if:
- symptoms do not improve after a week
- the individual has recently traveled abroad
- there is blood or mucus in the stool
There is no specific cure for rotavirus, but it usually resolves within 7 days. However, treatment for dehydration is essential.
Suitable fluids are water or an oral rehydration solution (ORS). Fruit juices and carbonated drinks are not recommended. These can worsen their symptoms of diarrhea.
ORS usually comes in sachets that are available without a prescription as an over-the-counter preparation from a pharmacist. They help to replace salt, glucose and other important minerals that are lost through dehydration.
If a person vomits after drinking an ORS solution, they should wait 5 to 10 minutes before taking more.
ORS should be ingested slowly, possibly a spoonful every few minutes, and every time the person passes a large volume of watery stool.
The exact amount of ORS depends on the size and weight of the individual. It is important to follow the instructions on the packet or those of the doctor or pharmacist.
If there is no sign or increased risk of dehydration, the person can consume what they normally would. In the case of infants, this includes breast milk, other milk feeds, and solids.
In severe case of dehydration, hospitalization may be necessary, to provide intravenous fluids.
As far as possible, a person with rotavirus infection should stay away from other people until 48 hours have passed after the last episode of diarrhea and vomiting.
Children should learn from an early age to wash their hands thoroughly after using the bathroom and before eating.
The toilet bowl should be cleaned thoroughly with disinfectant after each episode of diarrhea and vomiting.
Carers should wash their hands regularly, particularly after changing a diaper or cleaning bathrooms. The person's towels, flannels, cutlery, and eating utensils should not be shared with other members of the household.
As with adults, children should not return to nursery or school until 48 hours have passed since the last episode of diarrhea and vomiting.
The person should not enter a swimming pool for the first 2 weeks after their last episode of diarrhea. Even if there are no symptoms, research has found that the rotavirus can spread to other children via the pool water.
Vaccination can help protect children from the virus. It is not 100 percent effective, but it will prevent severe infection in 9 out of 10 children, and it will prevent infection in 7 out of 10 children.
The rotavirus vaccine is thought to prevent over 40,000 deaths per year.
The vaccines are:
The rotavirus vaccine was introduced in the U.S. in 2006. Before then, rotavirus was the main cause of severe diarrhea among infants and young children. and most children were affected by it before their fifth birthday.
This led to between 55,000 and 70,000 hospitalizations and 20 to 60 deaths each year. The vaccine is thought to prevent 40,000 to 50,000 hospitalizations each year.
The Centers for Disease Control and Prevention (CDC) estimate that:
"For about the first year of an infant's life, rotavirus vaccine provided 85-98 percent protection against severe rotavirus illness and hospitalization from rotavirus illness, and 74-87 percent protection against rotavirus illness of any severity."
Like all vaccinations, there is a chance of an allergic reaction in some children, and some adverse effects. Overall, however, the vaccination is considered "very safe."