Immunization Science

The article

Active, Population-based Surveillance for Severe Rotavirus Gastroenteritis in Children in the United States. Payne DC, Staat MA, Edwards KM, et al. 2008. Pediatrics 122(6): 1235-43.

The question

What were the disease burden and the characteristics of severe rotavirus illness in the United States before universal rotavirus vaccination?

The study

This prospective survey conducted from January through June, 2006 included children 14 days to 3 years of age living in 3 US counties (Hamilton County, Ohio; Davidson County, Tennessee; Monroe County, New York), who had diarrhea and/or vomiting. The parent or guardian completed a standardized questionnaire and stool samples were examined for rotaviruses.

The researchers excluded from the study children with symptoms for more than 10 days, who had been admitted to another (non-study) hospital for more than 48 hours, who had a non-infectious cause for diarrhea, who were immunocompromised, or whose parents did not wish their child included.

The findings

Rotavirus was detected in the stool of 50% of the children who were hospitalized or were seen in emergency rooms and from 27% of those who were seen in outpatient clinics (more samples were available from those who were hospitalized than those who were seen in the outpatient settings).

The overall rotavirus-related hospitalization rate was 22.5 admissions per 10,000 children less than 3 years of age. However, rates of rotavirus-related hospitalizations varied from 11.8–30.9 admissions per 10,000 children in the different counties.

Rotavirus-related hospitalization rates were highest for children 12 to 18 months of age and during February through April. There were 301 emergency room visits and 311.9 outpatient visits per 10,000 children that were rotavirus-related.

Extrapolating these numbers to the entire US population of children less than 3 years of age would imply that there were about 27,000 hospitalizations and more than 361,000 emergency room visits per year attributable to rotavirus. That is, every year, 1 in 150 children less than 3 years of age were hospitalized for rotavirus infection and 1 in 11 visited an emergency department; the authors estimated that another 1 in 11 children with rotavirus infection visited an outpatient clinic.

The relevance/bottom line

This study demonstrates the substantial disease burden in the US that was related to rotavirus infection in young children prior to the introduction of universal rotavirus vaccination later in 2006.

NNii’s comment

Although the disease burden from rotavirus in the US is far less than in developing countries, it is substantial however. Because rotavirus activity varies considerably from year to year and varies between geographic areas—as was observed across the study counties—caution must be exercised when these data are extrapolated to the entire US population or comparisons are made between years. Nevertheless, this study should serve as an important baseline for assessing the impact of universal rotavirus immunization in these communities in subsequent years.