Rotavirus is the leading cause of severe dehydrating diarrhea among children both in the United States and worldwide. It has been estimated that most children in the United States have or will be infected by 5 years of age. This very contagious virus is even resistant to good hygiene practices, including hand washing. What are the symptoms of rotavirus, and what can we do to prevent our children from getting the disease?
Type of Microbe: RNA Virus
How Rotavirus spreads: Person-to-person via the fecal-oral route. Rotavirus that is shed in stools of infected people can contaminate hands and objects and get passed to family members and close contacts.
How Rotavirus causes disease: Rotavirus makes a toxin called “NSP4 enterotoxin,” which alters the function of the intestines, causing increased fluid secretion and lactose intolerance.
Who’s at risk? Since rotavirus is very contagious, all people can get infected. Small children younger than 5 years of age, though, are at the greatest risk for severe dehydration that leads to hospitalization and sometimes death. In addition, people with weaker immune systems, such as the elderly or HIV patients, are also more likely to have severe symptoms. Approximately 40% to 50% of hospitalizations for diarrhea are due to rotavirus, and 20 to 60 deaths due to rotavirus occur each year in the United States. In developing countries, rotavirus causes more than 500,000 deaths each year in children less than 5 years of age.
Rotavirus infections are more common between November and May, coinciding with the time of year that children are in school and are more likely to be in closer contact with other children. In addition, the virus is commonly transmitted in close communities, such as daycare centers, nursing homes and within families.
Symptoms of Rotavirus Infection: Approximately two days following exposure to the virus, symptoms typically begin with mild fever, upset stomach, vomiting, followed by diarrhea that lasts 3 to 8 days. Loss of fluids can be accompanied with dehydration.
Diagnosis of Rotavirus: Rotavirus can be diagnosed by identification of the virus in the patient’s stool. The most common test is the “Enzyme Immunoassay," which uses an antibody that binds specifically to the virus to detect its presence. Other tests include use of specialized microscopes (electron microscopy), protein analysis (polyacrylamide gel electrophoresis) and analysis of genetic material (RT-PCR).
Prognosis: The infection is usually self-limiting for healthy people. Infections, however, that lead to severe diarrhea may result in hospitalization or death.
Treatment of Rotavirus Infection: Since the infection itself is self-limiting, treatment for rotavirus infections consists of oral rehydration therapy for individuals who are dehydrated from severe loss of fluids from diarrhea. Oral rehydration therapy (ORT) consists of a mixture of water, sugar and salts. In severe cases of dehydration, an emergency room visit and/or hospitalization may be necessary, during which an IV line is used for direct rehydration. If you suspect rotavirus infection (or any other severe diarrheal disease), talk with your medical provider about what to do.
Rotavirus Prevention: The bad news is that rotavirus is one microbe that is not easily prevented with good hygiene and sanitation. The good news is that there are two newly licensed vaccines to prevent Rotavirus disease. Rotarix (GSK) and RotaTeq® (Merck and Co.) have shown high rates of prevention and large reductions in hospitalizations due to rotavirus. (See FDA report on Rotarix:
http://www.fda.gov/bbs/topics/NEWS/2008/NEW01814.html). The CDC recommends universal immunization of infants against rotavirus.
Sources:
Lorrot M and Vasseur M. How do the rotavirus NSP4 and bacterial enterotoxins lead differently to diarrhea? Virology Journal. 2007; 4:31.
Rotavirus (Rotavirus Infection). Centers for Disease Control and Prevention
Rotavirus and related worms. USFDA Bad Bug Book. Center for Food Safety and Nutrition.
Vaccines and Preventable Diseases: Rotavirus Vaccination. Vaccines and Immunizations. Centers for Disease Control and Prevention.
