International Union for Circumpolar Health Ministry of Public Health and Social Development of RF Russian Academy of Medical Sciences Siberian Branch of Russian Academy of Medical Sciences Siberian Branch of Russian Academy of Sciences Medical Polar Fund “Science” The Northern Forum

Abstracts

Northern Epidemiology

Introduction: The International Circumpolar Surveillance (ICS) Network has been conducting population-based surveillance of invasive pneumococcal disease (IPD) since 1999. Canadian regions involved in ICS are Yukon, Northwest Territories, Nunavut, and northern regions of Québec and Labrador. The total population is 132,956 persons, of whom 59% are Aboriginal. Universal 7-valent pneumococcal conjugate (pcv7) vaccination of children under 2 years is recommended in Canada and was implemented during the surveillance period at various times. The recommendation for universal 23-valent polysaccharide vaccination for persons 65 years and older was in place throughout the surveillance period.

Methods: Clinical and demographic information were collected using standardized surveillance forms. Bacterial isolates were forwarded to Canadian reference laboratories for confirmation and serotyping.

Results: Between 1999-2004, 226 cases of IPD were reported. The crude annual incidence rates varied from 21.8 to 38.4 cases per 100,000 population per year. Children under 2 years of age had the highest incidence. The overall incidence remained stable, however the incidence among children under 2 years declined significantly throughout the time period. Eighty-five percent of cases occurred among Aboriginal people. The crude incidence among Aboriginals compared to non-Aboriginals was 38.0 vs 9.6 per 100,000 person-years. The most commonly reported clinical presentation was pneumonia (66.8%), followed by septicemia (20.4%) and meningitis (4.9%). The case fatality rate was 5.4%.

The majority of isolates (95.9%) were susceptible to penicillin. The most common serotype reported was type 1 (32.3%), however an outbreak occurred during the time period. Based on age and serotype analysis, 62.5% of cases among children under 2 years were preventable with pcv7 vaccine and 86.4% of cases among adults 65 years and older were preventable with 23-valent vaccine. In the two regions with universal pcv7 programs in place, 19 cases of preventable illness among children under 2 years occurred before program implementation and none after. There were no cases of vaccine failure reported among children under 2 years.

Conclusion: IPD is an important cause of morbidity among northern Canadians. Aboriginal people are particularly impacted. These data should guide prevention and control strategies, including immunization recommendations.

Note. Abstracts are published in author's edition

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Last update: 06-Jul-2012 (11:52:05)