Epidemiology of Haemophilus influenzae Serotype a, North American Arctic, 2000–2005

• Other Authors: Bruce, Michael G, Deeks, Shelley L, Zulz, Tammy, Navarro, Christine, Palacios, Carolina, Case, Cheryl, Hemsley, Colleen, Hennessy, Tom, Corriveau, Andre, Larke, Bryce, Sobel, Isaac, Lovgren, Marguerite, DeByle, Carolynn, Tsang, Raymond, Parkinson, Alan J, International Circumpolar Surveillance Hia Working Group
• Language: English
• Subjects: Adolescent; Adult; Age Factors; Aged; Child; Preschool; Female; Haemophilus Infections; Humans; Incidence; Infant; Alaska Natives; Inuit; Male; Middle Aged; Population Surveillance; Serotyping; Arctic; Canada; inuit; Alaska
• Online Access: https://stacks.cdc.gov/view/cdc/3181

Before the introduction of Haemophilus influenzae type b (Hib) conjugate vaccines, rates of invasive H influenzae disease among indigenous people of the North American Arctic were among the highest in the world Routine vaccination reduced rates to low levels; however, serotype replacement with non-type b strains may result in a reemergence of invasive disease in children We reviewed population-based data on invasive H influenzae in Alaska and northern Canada from 2000-2005; 138 cases were reported Among 88 typeable isolates, 42 (48%) were H influenzae type a (Hia); 35 (83%) occurred in indigenous peoples Among Hia patients, median age was 11 years; 62% were male; 1 adult died Common clinical manifestations included meningitis, pneumonia, and septic arthritis Overall annual incidence was 09 cases per 100,000 population Incidence among indigenous children <2 years of age in Alaska and northern Canada was 21 and 102, respectively Serotype a is now the most common H influenzae serotype in the North American Arctic; the highest rates are among indigenous children