A critical review on a globally-licensed, live, orally-administrable, monovalent human rotavirus vaccine: Rotarix

Abstract

Rotavirus is the major cause of severe gastroenteritis in children worldwide, and two, live, orally-administrable vaccines are licensed globally. They are Rotarix, a monovalent, human rotavirus-based vaccine (GlaxoSmithKline), and RotaTeq, a pentavalent, bovine–human reassortant vaccine (Merck). The RIX4414 strain, a G1P[8] virus, is contained in the Rotarix vaccine. It grows efficiently in the human intestine, as evidenced by vaccine virus shedding into faeces. Efficient multiplication of RIX4414 in the intestines may play a role in stimulating immune effectors other than neutralizing antibodies that may explain the protective immunity against fully heterotypic G2P[4] strains. The protective efficacy against severe rotavirus gastroenteritis afforded by Rotarix is consistently better against strains that share with RIX4414 both G and P serotypes (i.e., G1P[8]), or only P serotype (i.e., G3P[8], G4P[8] and G9P[8]). The Rotarix vaccine is safe regarding intussusception if its first dose is administered between 6 and 12 weeks of age and the last dose by 24 weeks of age with a minimum interval of 4 weeks between the two doses. The expansion by Advisory Committee on Immunization Practices, USA, of the age limit for the first dose to age <15 weeks, and the last dose by 8 months requires close monitoring.

Keywords::

• diarrhoea
• immunization
• intussusception
• rotavirus
• serotype
• vaccine efficacy

Note added in proof

The World Health Organization (WHO) Strategic Advisory Group of Experts (SAGE) recommends the inclusion of rotavirus vaccination of infants into all national immunization programmes. In countries where diarrhoeal deaths account for 10% or more of mortality among children age less than 5 years, the introduction of the vaccine is prioritized.

Notes