A review of invasiveHaemophilus influenzaedisease in the Indigenous populations of North America

Abstract

SUMMARYHistorically, the highest incidence rates of invasiveHaemophilus influenzaedisease in the world were found in North American and Australian Indigenous children. Although immunization againstH. influenzaetype b (Hib) led to a marked decrease in invasive Hib disease in countries where it was implemented, this disease has not been eliminated and its rates in Indigenous communities remain higher than in the general North American population. In this literature review, we examined the epidemiology of invasiveH. influenzaedisease in the pre-Hib vaccine era, effect of carriage on disease epidemiology, immune response toH. influenzaeinfection and Hib vaccination in Indigenous and Caucasian children, and the changing epidemiology after Hib conjugate vaccine has been in use for more than two decades in North America. We also explored reasons behind the continued high rates of invasiveH. influenzaedisease in Indigenous populations in North America.H. influenzaetype a (Hia) has emerged as a significant cause of severe disease in North American Indigenous communities. More research is needed to define the genotypic diversity of Hia and the disease burden that it causes in order to determine if a Hia vaccine is required to protect the vulnerable populations.