Universal mass vaccination program reduced rotavirus-related hospitalizations

Eighteen months after the institution of a universal mass vaccination program in Austria, the targeted age group of children aged 90 days to 20 months experienced a 74% drop in rotavirus gastroenteritis-related hospitalizations, according to recently published study results.

Researchers from Medical University Vienna, Austria and Tel Aviv University in Israel estimated that 44,900 episodes of rotavirus-related acute gastroenteritis occur and one in 60 children aged younger than 2 years will be hospitalized because of the disease in Austria every year. These numbers, along with cost considerations, led to the introduction of a universal mass vaccination program for Austrian infants in 2007.

The researchers examined the effect that the universal mass vaccination program had on rotavirus gastroenteritis-related hospitalizations by analyzing data from the pre-vaccination (2001 to 2006) and post-vaccination (2007 to 2008) periods in Austria.

The pentavalent rotavirus vaccine (RotaTeq) was distributed in oral form from July to December 2007 in Austria, but the monovalent vaccine (Rotarix) did not become available until 2008.

Children aged 15 years or younger who were hospitalized for rotavirus gastroenteritis in 11 pediatric hospitals within a sentinel network were included in the study, according to the researchers. They categorized children from the post-vaccination period by three age groups: children aged younger than 90 days who could only have received up to one dose of vaccine; children aged 90 days to 20 months who were eligible for full-course vaccination; and children aged 20 to 48 months who were “out of range” for vaccination.

Results indicated a 42% decrease in hospitalized children aged younger than 90 days after the introduction of the universal mass vaccination program between August 2007 and December 2008 when compared with identical pre-vaccination periods, according to the researchers. They also noted a significant decline of 73.6% for children aged 90 days to 20 months. Children aged 20 to 48 months, however, experienced an 8% increase in hospitalizations.

The researchers also said the number of hospital days of children with rotavirus gastroenteritis decreased 45% by 2008, suggesting that the universal mass vaccination program was cost-effective in preventing expenses related to hospitalizations.

The researchers also reported that vaccine coverage with RotaTeq was 59% in July to December 2007 but rose to 87% in 2008 after the introduction of Rotarix. Data analysis revealed that field effectiveness for both vaccines against rotavirus gastroenteritis-related hospitalization was between 61% and 98%.

“The data show the importance of an early start of immunization in the seventh week of life and also emphasizes that the mass vaccination program substantially reduces the burden caused by rotavirus infection,” the researchers wrote. – by Melissa Foster

Paulke-Korinek M. Pediatr Infect Dis J. 2010;29:319-323.

PERSPECTIVE

In the April 2010 issue of The Pediatric Infectious Disease Journal, Kollaritsch and colleagues reported on the effect of the introduction of routine infant rotavirus vaccination on rates of hospitalization for gastroenteritis in Austria. The researchers observed a dramatic decrease in hospitalization risk in the youngest children by 74%. These results were consistent with what has been observed in the United States and other countries and supported routine infant vaccination against rotavirus infection.

– Steven B. Black, MD

Infectious Diseases in Children Editorial Board