Proportion of hospitalizations due to
rotavirus in Toronto, Ontario**

Adapted from Ford-Jones EL et al¹⁶

Diarrhea was identified in 1638 hospitalized children. One thousand and one (61%) hospitalized children had stool specimens tested. Rotavirus was identified in 372 (37%) of tested specimens.

Peak seasonality of rotavirus infection generally occurs at the same time as other infections common to children, such as respiratory syncytial virus and influenza.^18,19 This co-occurrence can put increased stress on physicians' offices and pediatric emergency departments during those times.¹⁰

There are different strains (or serotypes) of rotaviruses. The prevalence of particular rotavirus serotypes is highly variable, often changing from one season to the next. Thus, each rotavirus season may be different, with no way to predict which serotype will be the most prevalent in a given season.^3,9

*This study tested stool samples from 565 children <5 years of age hospitalized for gastroenteritis between December 1999 and May 2000 in seven community and specialized hospitals in Quebec.

**Data from the Pediatric Rotavirus Epidemiology Study for Immunization (PRESI) study, a prospective, multisite cohort study. Data were collected between November 1997 and June 1998 in 18 hospitals serving the Toronto region. Hospitalization data obtained from 1638 children <5 years of age who were hospitalized for diarrhea, and prospective, centralized testing of their stools was performed.