Rotavirus vaccines [Rotavirus aşilari]

Rotavirus is a major cause of acute gastroenteritis worldwide and infects almost all children in the first 5 years of life, with severe, dehydrating gastroenteritis occurring primarily among children 4 to 36 months of age. Rotavirus causes an estimated 600.000 deaths and more than 2 million hospitalizations each year. 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 However, the vaccine was subsequently withdrawn because of a likely association with intestinal intussusception. Recently, the efficacy and safety of two new rotavirus vaccines, the monovalent human rotavirus vaccine (HRV, Rotarix) and the pentavalent human-bovine reassortant vaccine (PRV, RotaTeq), was evaluated in large scale trials of more than 130,000 infants. The two new rotavirus vaccines have shown good clinical efficacy in preventing rotavirus gastroenteritis, especially severe disease. These vaccines prevent about 74 percent of all rotavirus cases and about 98 percent of the most severe cases, including 96 percent of rotavirus cases requiring hospitalization. There was no association between the new rotavirus vaccines and increased risk of intussusception. Today, these two new rotavirus vaccines have been licensed in more than 90 countries and are used routinely in several countries such as USA, Mexico, Brazil, Venezuela and Panama. Vaccine doses should be administered at 2 and 4 months of age (2 doses for HRV) or at 2, 4, and 6 months (3 doses for PRV). The first dose should be administered between 6 and 12 weeks of age; immunization should not be initiated for infants older than 12 weeks of age (for PRV) or 14 weeks of age (for HRV). All doses of vaccine should be administered by 24 weeks of age (for HRV) or 32 weeks of age (for PRV)