Rotavirus vaccination: a concise review

Live attenuated oral rotavirus vaccines were tested for proof-of-concept in the early 1980s, the first vaccine (RotaShield, Wyeth) was introduced in 1998 but was subsequently withdrawn because of association with intussusception, and the two currently licensed vaccine (Rotarix, GlaxoSmithKline, and RotaTeq, Merck) were introduced in 2006. Before licensure both vaccines were extensively tested for safety (for intussusception) and efficacy in trials comprising in over 60,000 infants each. Rotarix is a single-strain human rotavirus vaccine (RV1) and RotaTeq is a combination of five bovine-human reassortant rotaviruses (RV5). Although the composition of the two vaccines is different, their field effectiveness and, largely, mechanism of action are similar. Both prevent effectively severe rotavirus gastroenteritis (RVGE) but are less efficacious against mild RVGE or rotavirus infection. Field effectiveness of these vaccines in Europe and the USA against severe RVGE has been above 90% and in Latin America around 80%. Trials in Africa have yielded efficacy rates between 50 and 80%. Rotavirus vaccination has been introduced into the national immunization programmes of about 20 countries in Latin America, with Brazil and Mexico as leading countries, as well as in the USA, Australia and South Africa. Introduction into other African countries will start in 2012. In Europe, Belgium, Luxembourg, Austria and Finland and five federal states of Germany have introduced universal rotavirus vaccination. The reasons for the slow progress in Europe include low mortality from RVGE, unfavourable cost-benefit calculations in some countries, and concerns that still exist over intussusception.