Rotavirus

Primary rotavirus infection is common in children 6 months to 2 years of age.

Rotavirus infection is the world's most common cause of severe viral gastroenteritis (vomiting and diarrhea).

• Primary rotavirus infection is common in children 6 months to 2 years of age.
• Infectious gastroenteritis (vomiting and diarrhea) may be caused (in order of frequency) either by viral, bacterial, or fungal agents.
• Four viral families cause the bulk of gastroenteritis. 
• Common symptoms include fever, vomiting, and non-bloody diarrhea.
• Oral fluids are the mainstay for those with mild to moderate disease.
• Complications of rotavirus infection are relatively rare.
• Two oral vaccination products are available including RotaTeq and Rotrix

Infectious gastroenteritis (vomiting and diarrhea) may be caused (in order of frequency) either by viral, bacterial, or fungal agents. There are four viral families that cause the bulk of gastroenteritis.

• As stated above, the rotavirus is responsible for the large majority of illnesses both worldwide and in the United States.
• Infection by the norovirus family is implicated in approximately one-third of all viral illnesses causing vomiting and diarrhea.
• Two other viral families (adenovirus and astrovirus) each cause a low percentage of intestinal disease.

While children are the predominant victims of rotavirus infection, adults (often caretakers or parents of these children) may experience the same symptoms of

• fever,
• vomiting, and
• non-bloody diarrhea.

Studies have shown a broad range of responses to rotavirus infection -- all the way from total lack of symptoms to severe illness that may be associated with dehydration and circulatory collapse. Hospitalized patients often have a total duration of disease averaging eight days. As would be expected, those who are less ill and remain at home tend to have less intense symptoms and generally recover more quickly.

Some studies of children with a rotavirus infection have pointed out that children may have respiratory symptoms (runny nose and cough) coexistent with their intestinal manifestations. Other researchers counter that an alternative interpretation of these findings implies two separate but simultaneous illnesses. Adults tend not to experience respiratory symptoms during a rotavirus illness.

Complications of rotavirus infection are relatively rare. Important exceptions are those infections in people with weakened immune systems (premature and newborn infants or the elderly). When access to modern medical supportive care is available (for example, IV solutions) severe morbidity and death are rare. However, in developing nations, where such services are scarce or unavailable, rotavirus infection may be life-threatening.

Indications for seeking medical guidance center around maintaining adequate hydration.

• Extreme lethargy, lack of tears, diminishment of saliva, and significant reduction of urinary output are all indicators of dehydration and suggest that the patient's vomiting and/or diarrhea may be more severe than can be safely managed on an outpatient basis.
• In infants, documentation of acute weight loss of greater than 5% is also an indicator of the need for professional intervention.

If outpatient management fails, intervention with IV fluids generally is necessary to correct dehydration, provide appropriate replacement fluids for ongoing losses due to vomiting and diarrhea, and guarantee daily fluid balances. Various formulas to calculate the necessary volume and composition of these fluids as well as their rate of administration are available. Correction of moderate to severe dehydration may require up to 24 hours. Accurate monitoring of intake (oral and IV) and output (vomiting and diarrhea) is imperative. Infants and toddlers should have daily weight measurements obtained.

Antibiotics have no place in the management of rotavirus-induced illness. A number of other therapeutic options have been developed to help control the symptoms of gastrointestinal illnesses. While some may have anecdotal benefits, they are generally not recommended for use in children. These include

• over-the-counter anti-motility drugs (for example, Imodium), which may tend to relieve the frequency and volume of diarrhea as well as lessen associated cramping.
• Pepto-Bismol is an over-the-counter preparation claiming to lessen the secretory capacity of the intestinal tract. Since it is metabolized to an aspirin-type product, it should not be used in people less than 18 years of age.
• Some products (for example, Kaopectate) promote their value as adsorbents.

There are some medications that have demonstrated conclusive benefits to control and correcting symptoms of rotavirus gastroenteritis. Administration of probiotics (for example, Lactobacillus species) is felt to be helpful in reestablishing the normal intestinal bacterial population.

• An antiemetic developed to control chemotherapy-induced vomiting (Zofran) has been shown to be safe and effective.
• Zinc supplementation has also been shown to be effective in controlling diarrhea.
• The effectiveness is most pronounced when treating children with chronic malnutrition in whom zinc deficiency is most likely to occur.

Outpatient management of rotavirus infection is designed to correct mild dehydration and ensure tolerance of adequate maintenance fluids and nutrition during the resolution phase of the illness. Oral fluids are the mainstay for those with mild to moderate disease. Ad lib (nonrestricted intake) breast milk for infants is always encouraged. For infants for whom breast milk is not an option, a commercially prepared solution of water, sugar, and electrolytes (for example, Pedialyte) is the fluid of choice. Older toddlers and young children may be offered an age-appropriate replacement fluid (for example, Gatorade). Once intestinal tolerance to these fluids has been established, a gradual reintroduction of age-appropriate solid fluids (including full-strength cow's milk) is reasonable. High-fat foods are often not well tolerated. Complex carbohydrates (vegetables/fruits), lean meat, and yogurt are generally acceptable food choices.

To limit the spread of illness at home or in an institutional setting (for example, day care), the importance of frequent hand washing with soap and water should not be underestimated. Having separate diaper changing areas and immediate disposal of a soiled diaper in a sealed container are also imperative. In developing countries, water purification systems are paramount for controlling rotavirus infection.

As previously noted, hand washing with soap and water, diaper-changing hygiene, and water-purification systems are all necessary to deal with an established rotavirus outbreak. A proactive vaccination program for infants against rotavirus disease has been advocated by the CDC and the American Academy of Pediatrics for several years. Two oral vaccination products are currently licensed for use in the United States. RotaTeq was approved by the FDA in 2006. Three doses are required at 2, 4, and 6 months of age. More recently, Rotarix has been approved by the FDA. Two doses are required at 2 and 4 months of age. Both formulations show excellent effectiveness in preventing severe rotavirus disease and protection against the severity of disease requiring hospitalization. Side effects occur in only a small percentage of those receiving the vaccines (mild vomiting and diarrhea). It is recommended that whenever possible, patients should receive the same vaccine product throughout their immunization series.

A rotavirus vaccination product (RotaShield) was licensed for use in 1998 but was rapidly removed from use when postmarketing studies demonstrated an increase in the frequency of intussusception (a form of intestinal obstruction) in vaccine recipients. No such relationship (or any other form of intestinal obstruction) has been demonstrated with either RotaTeq or Rotarix.