Rotavirus is a common cause of severe gastroenteritis in children and infants, and rotavirus gastroenteritis is a major cause of childhood death in developing countries. It results in a limited number of deaths in the United States; however, almost every child in the United States has had an episode of rotavirus infection by the age of five years. Many will have gastroenteritis, costing nearly $1 billion in physician, emergency department, and hospital visits each year. To address this problem, the Advisory Committee on Immunization Practices (ACIP) has released its recommendations for administration of a live, oral, human-bovine reassortant rotavirus vaccine (Rotateq).

Epidemiology

Although rotavirus infects most children by five years of age, severe gastroenteritis primarily occurs in children three to 35 months of age. Symptoms include vomiting followed by mild or severe diarrhea, which can cause dehydration, electrolyte imbalance, and in some cases, death. One third of patients also have a fever of 102°F (39°C). Gastrointestinal symptoms typically resolve in three to seven days.

Rotaviruses are transmitted through person-to-person contact, commonly through the fecal-oral route; the virus also can be transmitted through food and water or respiratory droplets. Its incidence peaks during the winter in the United States, starting in the Southwest in November or December and moving eastward to reach the Northeast by April or May.

Premature infants and children from lower socioeconomic backgrounds may have an increased risk of hospitalization from gastroenteritis. Immunocompromised persons are at greater risk of having severe, prolonged, and fatal rotavirus gastroenteritis. Travelers returning from developing countries, older adults, and child care providers also are at increased risk.

Laboratory Testing

The clinical features of rotavirus gastroenteritis do not vary from other forms of gastroenteritis, so laboratory tests on fecal specimens must be performed to confirm the diagnosis. An enzyme immunoassay directed at an antigen common to all group A rotaviruses is widely available, and commercial kits tend to be inexpensive, easy to use, and highly sensitive.

Serologic methods that detect immunoassay for rotavirus serum immunoglobulin G (IgG) and immunoglobulin A (IgA) antibodies have been used to confirm infections. In rotavirus vaccine trials, measuring rotavirus-specific IgA and neutralizing antibodies to vaccine strains has assessed the immunogenicity of the vaccines.

Clinical History

Good hygiene and clean water have little effect on the transmission of rotavirus, so improvements are unlikely to affect the prevention of the disease.

Forty percent of children initially infected with rotavirus are protected against future rotavirus infections; 75 percent are protected against rotavirus gastroenteritis; and 88 percent are protected from severe rotavirus gastroenteritis infection. Mild disease may still occur, but vaccination early in life would prevent all future instances of severe rotavirus disease.

Prevention

ROTAVIRUS VACCINE

Rotateq is a live, oral vaccine with five reassortant rotaviruses that were developed from human and bovine parent rotavirus strains. Its formulation contains sodium citrate, sucrose, sodium hydroxide, tissue culture media, polysorbate 80, and sodium phosphate monobasic monohydrate. Trace amounts of fetal bovine serum may also be present. It has been tested in three phase III trials, including nearly 70,000 infants—80 percent of which are from the United States and Finland. The vaccine should be refrigerated at 36 to 46°F (2 to 8°C) for no longer than 24 months.

Administering the Vaccine

ROUTINE ADMINISTRATION

ACIP recommends that U.S. infants receive routine rotavirus vaccinations given in three doses at two, four, and six months of age (Table 1). When an infant is six to 12 weeks of age, the first dose should be administered, and subsequent doses should be administered at four- to 10-week intervals, with all three doses given to the child before 32 weeks of age. Infants who are older than 12 weeks should not be given the initial rotavirus vaccination.

Infants who have had rotavirus gastroenteritis before the completion of the vaccination should still complete the vaccination schedule because an initial infection may only provide partial immunity. Breastfed infants; those with transient, mild illnesses; and those with low-grade fever can also receive the vaccination.

SIMULTANEOUS ADMINISTRATION

It is acceptable for the rotavirus vaccine to be administered with the Hib, hepatitis B, pneumococcal conjugate, DTaP, and inactivated poliovirus vaccines. Data show that the rotavirus vaccine will not interfere with the immune response from these vaccines, including the diphtheria and tetanus components of DTaP. However, insufficient immunogenicity data are available to confirm the lack of interference between the rotavirus vaccine and the pertussis component of DTaP.

CONTRAINDICATIONS

ACIP recommends against administering the rotavirus to infants who have severe hypersensitivity to any component in the vaccine or to infants who have had a serious allergic reaction to a previous dose of the rotavirus vaccine.

Precautions

ALTERED IMMUNOCOMPETENCE

Family physicians should consider the benefits and potential risks of administering the rotavirus vaccination to infants who are known or suspected to have altered immunocompetence. Children or adults who are immunocompromised because of hematopoietic transplantation, solid organ transplantation, or congenital immunodeficiency may experience severe, prolonged, or even fatal rotavirus gastroenteritis.

ACUTE GASTROENTERITIS

ACIP recommends against the administration of the rotavirus vaccine to infants who have acute, moderate-to-severe gastroenteritis until the condition improves. However, infants who have mild acute gastroenteritis can be vaccinated, especially when a delay in vaccination could make the child ineligible to receive the vaccine (i.e., if the infant is 13 weeks of age or older before the initial vaccination).

The vaccination has not been studied in infants with concurrent acute gastroenteritis, so ACIP stresses that the vaccine's immunogenicity and effectiveness could be compromised.

MODERATE-TO-SEVERE ILLNESS

It is recommended that infants with a moderate-to-severe illness be vaccinated as soon as they recover from the acute phase of the illness.

PREEXISTING CHRONIC GASTROINTESTINAL DISEASE

Infants who have preexisting chronic gastrointestinal conditions, but who are not undergoing immunosuppressive therapy, should be vaccinated. However, ACIP warns that the safety and effectiveness of the rotavirus vaccine have not been established in infants who have these preexisting conditions.

INTUSSUSCEPTION

The administration of a previously licensed rotavirus vaccine, rhesus-based tetravalent rotavirus vaccine (Rotashield, withdrawn), has been found to increase the risk of intussusception, so infants with a history of intussusception may be at a higher risk of a repeat episode than other infants. Studies in over 71,000 infants found no increase in the risk of this complication with the current vaccine.

Special Situations

PREMATURE INFANTS

Premature infants may be at increased risk of hospitalization from viral gastroenteritis during their first year of life. ACIP recommends the vaccination of premature infants only if they are six weeks of age or older, are being discharged from the hospital nursery, and are clinically stable. The benefits of the vaccine outweigh the theoretical risks.

EXPOSURE TO VACCINATED INFANTS BY IMMUNOCOMPROMISED PERSONS

Infants who live in households with persons who have or are suspected of having an immunodeficiency disorder can be vaccinated. To minimize potential virus transmission, all household members should wash their hands after contact with the feces of the vaccinated infant.

EXPOSURE TO VACCINATED INFANTS BY PREGNANT WOMEN

Infants who live in households with women who are pregnant can be vaccinated because the majority of women of childbearing age already have a preexisting immunity to rotavirus. There is no evidence suggesting that rotavirus infection poses any risk to the fetus.

REGURGITATION OF THE VACCINE

ACIP recommends that family physicians do not re-administer a rotavirus vaccination dose if an infant regurgitates or spits out the dose or vomits during the administration of the vaccine.

HOSPITALIZATION AFTER THE VACCINE

If a recently vaccinated child is hospitalized, ACIP stresses that only routine precautions need to be taken to prevent the spread of the vaccine virus to the rest of the hospital.

Reporting of Adverse Events

Any clinically significant or unexpected adverse events after the administration of the vaccine must be reported to the Vaccine Adverse Events Reporting System. The National Childhood Vaccine Injury Act requires that health care professionals report any event listed by the vaccine manufacturer as a contraindication to any doses of the vaccine, or any event listed in the Reportable Events Table (http://vaers.hhs.gov/reportable.htm) that occurs within a specified period after vaccination.

Cost-effectiveness Analysis

It is estimated that a national rotavirus vaccination program in which three doses of Rotateq are administered at two, four, and six months of age would result in 255,000 fewer physician visits, 137,000 fewer emergency department visits, 44,000 fewer hospitalizations, and 13 fewer deaths per year in children who are younger than five years.