Table 2. Adjusted annual cumulative incidence^† per 10,000 persons by age, Vadu, District Pune, India, May 2009–April 2011.

	May 2009–April 2010 (Year 1)*
	Acute Medical				Respiratory***				Influenza Virus Positive				% of Acute Medical and Respiratory Hospitalizations Associated with Influenza
Age (years)**	Adjusted Incidence†	95% CI			Adjusted Incidence†	95% CI			Adjusted Incidence†	95% CI			% of acute medical	% of respiratory
<1	463.2	374.3	-	567.9	361.5	281.0	-	453.1	11.3	1.3	-	37.6	2%	3%
1–4	345.5	306.2	-	387.1	244.3	211.8	-	280.6	54.3	39.7	-	73.2	16%	22%
5–14	178.7	159.6	-	199.6	128.7	112.4	-	146.5	61.8	50.6	-	74.5	35%	48%
15–29	268.4	251.6	-	286.2	174.4	160.8	-	188.9	67.1	58.8	-	76.4	25%	38%
30–44	164.4	147.7	-	182.7	100.8	87.6	-	115.2	25.2	19.0	-	33.2	15%	25%
45–59	165.0	140.2	-	192.3	110.0	89.6	-	132.4	18.3	11.1	-	29.7	11%	17%
60+	160.3	130.6	-	193.8	102.2	78.7	-	129.7	11.6	4.4	-	22.6	7%	11%
all ages	223.6	214.4	-	233.0	149.1	141.7	-	156.9	46.8	42.6	-	51.2	21%	31%

^†Incidences were adjusted for health utilization at non-study facilities using the following formula: adjusted hospitalization incidence = (unadjusted incidence)/(% of acute medical hospitalizations reported on health utilization survey that occurred at study facilities).

^*From 2009 and 2010 mid-year population estimates from Vadu HDSS.

^**Adjustment factor = proportion of acute medical hospitalizations reported on HUS that occurred at study facilities: 0.46 for persons aged <1 year, 0.50 for 1–4 years, 0.78 for 5–14 years, 0.73 for 15–29 years, 0.76 for 30–44 years, 0.68 for 45–59 years, 0.67 for >60 years.

^***Defined as one or more respiratory symptoms in persons ≥5 years: cough, runny nose, sore throat, breathing difficulty or ear ache.

Defined as one or more respiratory symptoms in persons <5 years: cough, runny nose, fast breathing, or ear ache.