Rotavirus Vaccine Prevents Most Cases in Infants and Children

Rotavirus is a very common cause of gastroenteritis (sometimes called "stomach flu") in infants and young children. Rotavirus disease usually starts with fever, an upset stomach, and vomiting, and is followed by diarrhea. Rotavirus occurs most often in the winter and spring, usually in the months between November and May. Rotavirus is very contagious, spreading easily from children who are already infected to other children.

Once children have been exposed to rotavirus, it takes about two days for symptoms to appear. Children who are infected with rotavirus develop vomiting and watery diarrhea that lasts from three to eight days. They might lose interest in eating and drinking and become dehydrated from loss of fluids.

Nearly every child in the US has been infected with rotavirus by age 5. A child may develop rotavirus disease more than once because there are many different rotavirus types, but second infections tend to be less severe than the original infections. Likewise, adults can also be infected, though the illness tends to be mild.

Svapna Sabnis, MD, Assistant Professor of Pediatrics at the Medical College of Wisconsin, says, "The US Centers for Disease Control and Prevention (CDC) reports that each year, rotavirus is responsible for more than 400,000 doctor visits, more than 200,000 emergency room visits, 55,000-70,000 hospitalizations, and between 20 and 60 deaths in US children younger than 5 years of age."

Although death from rotavirus is not common in the US, says Dr. Sabnis, "in developing countries, rotavirus has been estimated to cause up to several hundred thousand deaths annually in infants and young children.

Vaccine Approved for Children
In February 2006, the US Food and Drug Administration (FDA) approved a live, oral vaccine against rotavirus called RotaTeq. "The vaccine is recommended for infants at 2, 4 and 6 months," says Dr. Sabnis. Dr. Sabnis, who sits on the Wisconsin Council for Immunization Practices, says that in her practice at the Downtown Health Center, "We offer rotavirus vaccine routinely to all eligible children, because this is such a common childhood virus."

The RotaTeq vaccine is quite effective, says Dr. Sabnis. "The vaccine helps prevent approximately 3/4 of cases of rotavirus disease, and almost all of the most severe cases, including those needing hospitalization." Side effects are minimal, she notes. "After receiving the vaccine, less than 3% of children may develop mild vomiting or diarrhea."

"The RotaTeq vaccine has great potential to save lives, particularly in developing nations with high mortality rates from rotavirus," says Dr. Sabnis. "Unfortunately at this time the vaccine is quite expensive."

Dr. Sabnis says that the vaccine should not be given to children who have had a severe reaction to the vaccine or its components. In addition, she says, "children who have problems with their immune system or gastrointestinal system, a history of intussusception (bowel obstruction), or moderate to severe illness (including gastroenteritis) at the time of the visit should not receive this vaccine."

Different from Previous Vaccine
The RotaTeq vaccine is different from the previous rotavirus vaccine. "The RotaShield vaccine was withdrawn in 1999 because it was found to be associated with intussusception," says Dr. Sabnis.

Intussusception is a rare blockage or twisting of the intestine, which can be life threatening. One portion of the intestine telescopes into another portion, causing an obstruction. The most common site of intussusception is where the small intestine joins the large intestine.

Because the two walls of the intestines press against each other, this causes inflammation, swelling, and eventually decreased blood flow. If intussusception is not detected early, internal bleeding, a hole in the intestines, or infection in the abdomen can occur because the intestinal tissue has died from the decreased blood flow. Intussusception occurs spontaneously in approximately 1 in 2,000 healthy young infants and children per year, but occurred at an increased rate during the first week or two following vaccination with the previous rotavirus vaccine.

The RotaTeq vaccine has been very carefully tested for any problems with intussusception. Dr. Sabnis says, "In a study of the new vaccine involving over 70,000 children, there was no association found between intussusception and RotaTeq." Additionally, the vaccine was not associated with an increased risk of any other serious side effects.

Dr. Sabnis says the CDC plans a large study to continue to monitor and collect data on the safety of the vaccine.

Diagnosis and Treatment
Unfortunately, there are patients who have not yet received the rotavirus vaccine. In these cases, diagnosis of rotavirus infection centers mainly on testing. Physicians test the stool of patients with gastroenteritis, to determine what is causing their illness; rotavirus and Norwalk virus are the most commonly diagnosed causes of gastroenteritis. In most cases, rotavirus gastroenteritis resolves on its own, although about one in 40 children with rotavirus gastroenteritis will require hospitalization for intravenous fluids. Antibiotics are not used for treatment, as rotavirus is not a bacterium, but a virus.

The goal of the treatment of any gastroenteritis, including rotavirus, is to prevent dehydration. Fluids and electrolytes (salt and minerals) lost from vomiting or diarrhea must be replaced as soon as possible. Juice, soda, and water do not replace electrolytes, but electrolyte and fluid replacement solutions for children are available in most food and drug stores.

Since the risk of dehydration is greater in infants and young children, parents should closely monitor the number of wet diapers changed per day when the child is sick.

While children have diarrhea, parents should avoid giving them caffeine, greasy and/or sweet foods, and foods that are high in fiber. Soft, bland foods are recommended, starting with bananas, rice, crackers, and toast, and moving on to boiled potatoes, cooked carrots, or baked skinless chicken.

Prevention of rotavirus is two-fold, involving both good hygiene and vaccination. "A clean water supply, uncontaminated food, and frequent hand washing are good preventive measures for all stomach viruses," says Dr. Sabnis. In addition, the RotaTeq vaccine brings added assurance to parents who want to prevent their children from becoming ill.

P. J. Early
HealthLink Contributing Writer

This article includes information from the US Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH), the National Institute of Diabetes and Digestive and Kidney Diseases, and the US Food and Drug Administration (FDA).

MCW Health News presents up-to-date information on patient care and medical research by the physicians of the Medical College of Wisconsin.