Rotavirus vaccine [Rotavirus aşi{dotless}si{dotless}]

Rotavirus is a major cause of severe gastroenteritis among children aged 5 years. Worldwide, rotavirus causes an estimated 600.000 deaths and more than 2 million hospitalizations each year. In addition to causing morbidity and mortality in children, rotavirus gastroenteritis creates a major economic burden on health care systems and families. A tetravalent, rhesus-human reassortant rotavirus vaccine (Rotashield) was licensed in 1998 for routine immunization of infants in the United States. However, the vaccine was subsequently withdrawn because of a likely association with intestinal intussusception. In 2007, the two new rotavirus vaccines [monovalent human rotavirus vaccine (RV1, Rotarix) and pentavalent human-bovine reassortant vaccine (RV5, RotaTeq)] have shown good clinical efficacy in preventing rotavirus gastroenteritis, especially severe disease. There was no association between the new rotavirus vaccines and an increased risk of intussusception Clinical studies and post-licensure surveillance data suggest that both rotavirus vaccines have provided adequate protection against rotavirus gastroenteritis in high- and middle-income countries in the Americas and Europe. In these countries, the rotavirus vaccines prevent about 98 percent of the most severe cases, including 96 percent of rotavirus cases requiring hospitalization. Although protective efficacy rates are lower than those from developed and middle-income countries, public-health impact of rotavirus vaccines in underdeveloped countries is more significant. The episodes of severe rotavirus gastroenteritis prevented in Malawian children were greater than those of the South African children: 6.7 versus 4.2 episodes per 100 vaccinated infants, respectively. In June 2009, the WHO's recommended the inclusion of rotavirus vaccination in the national immunization programs of all regions of the world. Vaccine doses should be administered at 2 and 4 months of age (2 doses for RV1) or at 2, 4, and 6 months (3 doses for RV5). The first dose should be administered between 6 and 12 weeks of age; immunization should not be initiated for infants aged 15 weeks and older and all doses of vaccine should be administered by age 8 months