Epidemiology and Infection

A review of invasive Haemophilus influenzae disease in the Indigenous populations of North America

R. S. W. TSANGa1, M. G. BRUCEa2, M. LEMa3, L. BARRETOa4 and M. ULANOVAa5 c1

a1 National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada

a2 Arctic Investigations Program, Division of Preparedness and Emerging Infections, U.S. Centers for Disease Prevention and Control (CDC), Anchorage, AK, USA

a3 Fraser Health Authority, Abbotsford, BC, Canada

a4 Human Health Therapeutics Portfolio, National Research Council of Canada, Ottawa, ON, Canada

a5 Medical Sciences Division, Northern Ontario School of Medicine, Thunder Bay, ON, Canada

SUMMARY

Historically, the highest incidence rates of invasive Haemophilus influenzae disease in the world were found in North American and Australian Indigenous children. Although immunization against H. influenzae type 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 invasive H. influenzae disease in the pre-Hib vaccine era, effect of carriage on disease epidemiology, immune response to H. influenzae infection 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 invasive H. influenzae disease in Indigenous populations in North America. H. influenzae type 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.

(Received November 12 2013)

(Revised January 30 2014)

(Accepted February 04 2014)

(Online publication March 05 2014)

Key words

  • Haemophilus influenzae ;
  • Haemophilus influenzae vaccine (type b);
  • infectious disease epidemiology;
  • immunoepidemiology;
  • Indigenous populations

Correspondence

c1 Author for correspondence: Dr M. Ulanova, Division of Medical Sciences, Northern Ontario School of Medicine, Lakehead University, 955 Oliver Road, Thunder Bay, ON, P7B 5E1, Canada. (Email: Marina.Ulanova@nosm.ca)

Metrics