Rotavirus is the most common cause of severe gastroenteritis in infants and young children. Before rotavirus vaccine became available, it was estimated that nearly every child in the United States was infected with rotavirus by five years of age, and most infected children developed gastroenteritis. Rotavirus causes more than 400,000 physician visits, up to 70,000 hospitalizations, and 20 to 70 childhood deaths each year.

A live, oral human-bovine reassortant rotavirus vaccine (RV5; Rotateq) was approved in 2006, followed by a live, oral human attenuated rotavirus vaccine (RV1; Rotarix) in 2008. Since the licensure of RV1, the American Academy of Pediatrics (AAP) has updated its guidelines on the routine use of rotavirus vaccine in infants.

Vaccines

RV5 contains five live reassortant rotavirus strains, four of which express one of the outer-capsid proteins (G1, G2, G3, or G4) from the human rotavirus parent strain and the attachment protein (P7[5]) from the bovine rotavirus parent strain. The fifth reassortant virus expresses the attachment protein (P1A[8]) from the human rotavirus parent strain and the outer capsid protein G6 from the bovine rotavirus parent strain. In prelicensure clinical trials, the effectiveness of RV5 against severe rotavirus gastroenteritis and any rotavirus gastroenteritis was 98 and 74 percent, respectively.

RV1 contains the RIX4414 strain of the human rotavirus G1P[8]. This strain was developed from rotavirus strain 89-12. RV1 is 85 to 96 percent effective against severe rotavirus gastroenteritis and 87 percent effective against any rotavirus gastroenteritis.

Both vaccines are well tolerated and have a low reactogenicity profile when given alone. Neither vaccine increases the risk of fever or irritability. RV5 confers an increased risk of diarrhea and vomiting, but these symptoms generally are mild and do not require treatment. Neither vaccine increases the risk of intussusception.

Recommendations

DOSING

The AAP recommends routine immunization of infants with either RV1 or RV5. If RV5 is used, it should be administered orally in a three-dose series at two, four, and six months of age. If RV1 is used, it should be given orally in a two-dose series at two and four months of age. Rotavirus vaccine may be administered to infants with minor acute illness.

Regardless of which vaccine is used, the first dose should be given between six weeks and 14 weeks and six days of age. Immunization should not be initiated in infants 15 weeks or older because of insufficient safety data for vaccine use in older children. If the first dose of rotavirus is inadvertently administered at or after 15 weeks of age, the remaining doses should be completed on schedule, because timing of the first dose should not affect the safety and effectiveness of subsequent doses.

The minimum interval between doses is four weeks. All doses should be given by eight months of age. Infants who have rotavirus gastroenteritis before they have received the full vaccine series should begin or complete the schedule following the age and interval recommendations, because the initial rotavirus infection provides only partial protection against subsequent disease.

Breastfeeding before or after administration of the rotavirus vaccine is encouraged. Breastfed infants should be immunized according to the same schedule as those who are not breastfed.

Vaccine should not be readministered to infants who regurgitate, spit out, or vomit during or after administration of the vaccine. The infants should receive the remaining doses of vaccine according to schedule.

SIMULTANEOUS ADMINISTRATION

Rotavirus vaccine may be administered concurrently with diphtheria and tetanus toxoids and acellular pertussis vaccine, Haemophilus influenzae type b vaccine, inactivated poliovirus vaccine, hepatitis B vaccine, and pneumococcal conjugate vaccine (Prevnar). In infants older than six months, rotavirus vaccine can also be administered concurrently with trivalent inactivated influenza vaccine.

INTERCHANGEABILITY OF ROTAVIRUS VACCINES

Ideally, the rotavirus vaccine series should be completed with the same product. However, vaccination should not be deferred because the product used for previous doses is unavailable. In such cases, the series should be continued with the product that is available. If any dose in the series was RV5, or if the product is unknown for any dose in the series, a total of three doses should be administered.

SPECIAL SITUATIONS

Preterm infants (i.e., those born before 37 weeks' gestation) should be immunized on the same schedule and with the same precautions as term infants if they are clinically stable and meet the age requirements for rotavirus vaccine (six weeks to 14 weeks and six days of age for the first dose). Because vaccine strains of rotavirus are shed in the stools of immunized infants, preterm infants in neonatal intensive care units (NICUs) or nurseries who are age-eligible and clinically stable may be immunized at the time of discharge. If an immunized preterm infant is readmitted to the NICU within two weeks after vaccine administration, contact precautions should be instituted and maintained for two to three weeks after vaccine administration.

Infants living in households with immunocompromised persons or pregnant women may be immunized. Most women of childbearing age have preexisting immunity to rotavirus, so the risk of infection is low. Most experts believe that the protection afforded to an immunocompromised person by immunizing the infant in the household and preventing wild-type rotavirus disease outweighs the small risk of transmitting vaccine virus.

Rotavirus vaccine may be administered at any time before, concurrent with, or after administration of any blood product, including antibody-containing products.

If a recently immunized infant is hospitalized, no precautions other than standard precautions need to be taken to prevent the spread of vaccine virus in the hospital setting.

Contraindications and Precautions

Rotavirus vaccine should not be administered to infants with a history of severe allergic reaction (e.g., anaphylaxis) after a previous dose of rotavirus vaccine or to a vaccine component. Because the applicator for RV1 contains latex, infants with a severe allergy to latex should receive RV5 instead.

Physicians should weigh the potential risks and benefits of administering rotavirus vaccine to immunocompromised infants; consultation with an immunologist or infectious diseases subspecialist is recommended.

Rotavirus vaccine should not be administered to infants with acute, moderate to severe gastroenteritis until the condition improves. Those with mild acute gastroenteritis may be immunized, particularly if a delay could be substantial. Vaccination also should not be delayed because of mild respiratory tract illness, with or without fever. As with all vaccines, the presence of a moderate to severe acute illness is a precaution to administration of rotavirus vaccine.

Infants with preexisting gastrointestinal tract conditions (e.g., congenital malabsorption syndromes, Hirschsprung disease) who are not undergoing immunosuppressive therapy should benefit from rotavirus vaccination.

Although neither RV5 nor RV1 is associated with an increased risk of intussusception, a previously licensed rotavirus vaccine, Rotashield, was associated with an increased risk. No data are available on the administration of rotavirus vaccine in infants with a history of intussusception; therefore, physicians should consider the potential risks and benefits of vaccination in these patients.