Diarrhea-associated health care utilization and costs have decreased considerably since the introduction of routine rotavirus vaccination in infants in 2006, a study has shown.
An assessment of pentavalent rotavirus vaccine (RV5) coverage from July 2007 through June 2009 in children under age 5 years showed that 73% of children under age 1 year, 64% of children aged 1 year, and 8% of children aged 2-4 years received at least one RV5 dose by Dec. 31, 2008. Rates of diarrhea-related hospitalizations declined by 33% from the 2001-2006 time period to 2007-2008 (from 52 to 35 per 10,000 person-years) and by 25% from 2001-2006 to 2008-2009 (from 52 to 39 cases per 10,000 person-years), Dr. Jennifer E. Cortes and her colleagues at the Centers for Disease Control and Prevention reported in the Sept. 22 issue of the New England Journal of Medicine.
Furthermore, the rates of hospitalization that were specifically coded for rotavirus infection declined by nearly 75% from 2001-2006 to 2007-2008 (from 14 to 4 per 10,000 person-years), and by nearly 60% from 2001-2006 to 2008-2009 (from 14 to 6 per 10,000 person-years), the investigators found (N. Engl. J. Med. 2011;365:1108-17).
Emergency department and outpatient visits for diarrhea also declined in 2007-2008 (by 9% and 3%), but the rates of visits in 2008-2009 were similar to prevaccine rates.
Overall, all regions had significant reductions in the rate of hospitalization for diarrhea for children under age 5 years, and in 2007-2008, all regions except the West had declines in emergency department and outpatient visits – although to a lesser extent than for hospitalizations, they noted.
The direct benefits of vaccination include an 89% reduction in rotavirus-coded hospitalizations in vaccinated vs. unvaccinated children in the two postvaccine rotavirus seasons studied, and 44% and 58% reductions in hospitalizations for diarrhea due to any cause in vaccinated vs. unvaccinated children in 2007-2008 and 2008-2009, the investigators said.
Emergency department visits also declined by 37% and 48% in vaccinated vs. unvaccinated children in 2007-2008 and 2008-2009, as did outpatient visits, which declined by 9% and 12% in vaccinated vs. unvaccinated children in 2007-2008 and 2008-2009.
Indirect benefits of vaccination included substantial reductions in the rates of health care utilization for diarrhea due to any cause, and for rotavirus-coded diarrhea among age-eligible, unvaccinated children during the January to June period (peak rotavirus season) of 2008, they noted.
The effects of vaccination on health care utilization translate to an estimated savings of $278 million in hospitalization costs over the 2-year period, Dr. Cortes and her associates said.
"This study provides more evidence that vaccinating against rotavirus substantially reduces suffering and health care costs for this common childhood illness," Dr. Mark Pallansch, director of CDC’s division of viral diseases, said in a written statement. "As more children get vaccinated against rotavirus, we expect to see even greater reductions in disease among all age groups."
For the study, the investigators used MarketScan Commercial Claims and Encounters databases that captured data on more than 2 million children under age 5 years to correlate RV5 coverage with changes in the rates of diarrhea-related hospitalizations, emergency department and outpatient visits, and related health care costs following RV5 introduction. Vaccine coverage was ascertained from a cohort of nearly 300,000 children under age 5 years from 37 states.
"Our findings confirm other reports of a decline in rotavirus activity in the United States after the introduction of rotavirus vaccine," the investigators noted, adding that their findings are generally consistent with the efficacy of the vaccine in prelicensure trials.
Indirect benefits were seen in 2007-2008, when declines in rotavirus disease "greatly exceeded expected declines, given the level of RV5 coverage," but were smaller in 2008-2009.
Although limited by several factors, such as a lack of data on uninsured and Medicaid populations, examination of data from only two postvaccine rotavirus seasons, and possible inconsistencies in rotavirus testing and coding across health care settings, the study nonetheless indicates that diarrhea-associated health care utilization and medical expenditures have declined since implementation of routine rotavirus vaccination in infants in the United States.
"Continued surveillance is needed to further characterize direct and indirect vaccine effects, including those of the recently approved rotavirus vaccine RV1, on diarrhea-associated health care utilization among U.S. children," Dr. Cortes and her associates concluded.
Dr. Cortes and her associates said they had no relevant financial disclosures.