Epidemiological Features of Pertussis in Hospitalized Patients in Canada, 1991‐1997: Report of the Immunization Monitoring Program–Active (IMPACT)

Abstract

To assess the morbidity associated with the continued high levels of pertussis, we studied all children .2 years of age who were admitted to the 11 Immunization Monitoring Program-Active (IMPACT) centers, which constitute 85% of Canada's tertiary care pediatric beds. In the 7 years preceding implementation of acellular pertussis vaccine, a total of 1,082 pertussis cases were reported, of which 49.1% were culture-confirmed. The median age of the patients was 12.4 weeks; 78.9% of cases were in children P = .001) and intensive care was required more frequently (19.2% vs. 4.9%; P = .001) in infants under <6 months of age than in those ⩾6 months. Pertussis continues to cause significant morbidity and occasional mortality in Canada, particularly in young infants.