Higher pertussis hospitalization rates in indigenous Australian infants, and delayed vaccination.

This ecological study aimed to identify possible reasons for higher pertussis hospitalization rates in indigenous Australian infants. Two national datasets were analysed: the Hospital Morbidity Database and the Australian Childhood Immunisation Register (ACIR). Most (52%) pertussis hospitalizations in indigenous infants occurred at 0-2 months of age, and rates in these indigenous infants were significantly higher in remote areas. Indigenous infants had higher hospitalization rates and more frequently delayed vaccination than non-indigenous infants of the same age. These data suggest that residence in a remote area, as a proxy for poorer living conditions for indigenous people, and delayed vaccination, both contribute to higher pertussis hospitalization rates in indigenous infants.