Rate (per 1,000) and 95% confidence limits of influenza-associated severe acute respiratory illness (SARI) among persons ≥5 years of age in Kenya, August 2009 to July 2011, using the Karemo division denominator (see methods).

DHS is Demographic and Health Survey; ARI is acute respiratory illness; HUS is Healthcare Utilization Survey; CL is confidence limit. The base province (Nyanza), where Karemo division is located, is bolded. 1This adjustment factor is based on 3 risk factors for SARI and healthcare-seeking behaviors, adjusting the rate of the base province in bold to the other provinces. ( from Equation 2a). 2This adjustment factor is used to estimate the rate of non-hospitalized cases assumed to be of the same severity as hospitalized cases. ( from Equation 4). 3Base rate for Karemo division surveillance (Nyanza province) among persons ≥5 in August 2009 to July 2010 is 3.13 per 1,000 persons per year. 4Base rate for Karemo division surveillance (Nyanza province) among persons ≥5 in August 2010 to July 2011 is 3.25 per 1,000 persons per year.