RESUMO
OBJECTIVES: First Nations communities in Manitoba were significantly affected by the pandemic H1N1 influenza virus (pH1N1) in 2009. Our objective was to conduct an epidemiologic investigation of a pH1N1 outbreak in one remote First Nations community (population 3,300) in northern Manitoba to inform a timely public health response and provide recommendations for preventing future outbreaks. METHODS: Chart reviews were conducted at the nursing station for patients meeting the influenza-like illness (ILI) case definition during the study period (April 20 to June 11, 2009). Descriptive analyses examined age, gender, clinical presentation, management, outcomes and risk factors. Comparisons were made for hospitalized versus non-hospitalized cases and laboratory-confirmed versus possible cases using Pearson's chi-square test for gender and symptoms and using a t-test for age. RESULTS: There were 180 ILI cases, including 23 laboratory-confirmed cases of pH1N1. Forty percent of children < 1 year old in the community and 9.4% of pregnant women presented to the nursing station with ILI. Most ILI cases were managed through the community nursing station, although 18.3% of cases (n = 33) were medically evacuated and 16.1% (n = 29) were hospitalized. There were no differences between hospitalized versus non-hospitalized or laboratory-confirmed versus possible cases. Risk factors identified in a subset of cases included exposure to an individual with ILI prior to illness onset, overcrowding and inadequate access to household water. CONCLUSIONS: Early arrival and rapid transmission of pH1N1 rendered usual non-pharmacological control measures largely ineffective. Recommendations for prevention of future outbreaks include an effective communications strategy and daily surveillance for disease detection and monitoring. Key determinants of health should be addressed in remote First Nations communities to prevent disease and protect the health of these populations.
