Invasive Infections Caused by Haemophilus influenzae Serotypes in Twelve Canadian IMPACT Centers, 1996–2001

Abstract

In 1996-2001, two-thirds of H. influenzae invasive disease in the 12 IMPACT centers was caused by non-b serotypes, which were associated with significant morbidity and mortality.

Invasive disease caused by Haemophilus influenzae type a in Northern Ontario First Nations communities

“…19.6 % of the population (Statistics Canada, 2006). Previous studies found a high incidence of invasive Hia disease among North American aboriginal people, including Canadian First Nations (Hammitt et al, 2005;Millar et al, 2005;McConnell et al, 2007;Bruce et al, 2008). According to Bruce et al (2008), the incidence rate of invasive Hia disease in the North American Arctic was 2.9/ 100 000 for indigenous and 0.2/100 000 for non-indigenous people.…”

“…with an annual incidence rate of 20.2/100 000 for children under the age of 5 years (Millar et al, 2005). In the Keewatin Region of Nunavut (northern Canada), the estimated incidence of invasive Hia disease was 418.7/100 000 for Inuit children under 5 years old (McConnell et al, 2007). In four Canadian western provinces (British Columbia, Alberta, Saskatchewan and Manitoba), the rate of invasive Hia disease among aboriginal children under 5 years of age was 3.7/100 000 (McConnell et al, 2007).…”

“…In the Keewatin Region of Nunavut (northern Canada), the estimated incidence of invasive Hia disease was 418.7/100 000 for Inuit children under 5 years old (McConnell et al, 2007). In four Canadian western provinces (British Columbia, Alberta, Saskatchewan and Manitoba), the rate of invasive Hia disease among aboriginal children under 5 years of age was 3.7/100 000 (McConnell et al, 2007). Previous studies found that similar risk factors can predispose to invasive Hia as to Hib disease, i.e.…”

“…between Europe and America. The role of the genetic background as a predisposing factor to invasive disease caused by certain capsular types of H. influenzae remains unexplored, although some studies suggest an increased incidence of invasive H. influenzae type a (Hia) disease among indigenous people of North America (Millar et al, 2005;McConnell et al, 2007;Bruce et al, 2008). We describe seven epidemiologically unrelated cases of invasive Hia disease that occurred in First Nations communities of Northwestern Ontario (Canada) during 2004-2008.…”

Haemophilus influenzae Infections in the H. influenzae Type b Conjugate Vaccine Era

“…Several recent surveys have utilized various study designs to monitor invasive H. influenzae disease in several countries throughout the world in the Hib conjugate vaccine era (1,3,10,19,20,22,23,27,35,46). The following statements summarize the main conclusions from these studies.…”