This study describes the reduction in acute gastroenteritis hospitalizations among children after introduction of rotavirus vaccine in the United States.
Reduction in acute gastroenteritis hospitalizations among US children after introduction of rotavirus vaccine: Analysis of hospital discharge data from 18 US States. Curns AT, Steiner CA, Barrett M, et al. Journal of Infectious Diseases 2010; 201: 1617-24.
Explanatory Note: Rotaviruses are intestinal viruses that infect virtually all children by three years of age. They are the most common cause of diarrhea in children. The illness often includes fever and vomiting and occurs primarily during the winter. Although most cases of infection are mild, about 1 in 50 cases develop severe dehydration requiring hospitalization. Prior to the introduction of a vaccine in 2006 in the United States, rotavirus infections resulted in at least 1 in 7 children visiting an emergency room or visited an outpatient clinic, 1 in 70 being hospitalized and 1 of 200,000 died. In developing countries, rotavirus leads to an estimated 480,000 to 640,000 deaths each year. The first of two new rotavirus vaccines was introduced in the US in 2006, having demonstrated 96% efficacy in preventing serious rotavirus disease (hospitalization) in pre-licensure trials. During 2008, it is estimated that more than half of 3 month old children had received one dose of vaccine and about one third of children who were old enough had received all 3 doses of the vaccine.
Were hospitalization rates for acute gastroenteritis (vomiting and diarrhea from all causes) among children less than 5 years of age lower after the rotavirus vaccine was introduced than before rotavirus vaccine was introduced?
Eighteen States contributed all of their hospitalization data for analysis. The researchers compared the hospitalization rates for children with gastroenteritis during the winter season (January through June) of 2007 and 2008 with the rates during the winters of 2000 through 2006.
During the winter seasons prior to vaccine introduction, the rates of hospitalization for acute gastroenteritis ranged from 97.3 to 118.2 per 10,000 children. In 2007 and 2008 the rates were 85.5 and 55.5 per 10,000 children, respectively, which was a highly significant difference.
For all age groups of children less than 5 years of age, the hospitalization rates for acute gastroenteritis during the winter season were lower than the rates observed before the introduction of the rotavirus vaccine. Rates for hospitalization for acute gastroenteritis for these years during July through August (41.1-51.7 per 10,000) were not significantly different.
The introduction of rotavirus vaccine in 2006 was associated with a large reduction in hospitalizations for acute gastroenteritis across 18 States, including among children too young and too old to have received the vaccine.
Rotavirus vaccines do not prevent rotavirus infection but rather protect against severe infection requiring hospitalization. In addition to protecting children who received the vaccine, this rotavirus vaccine had an indirect effect on children who had not been immunized (See Community Immunity).