Volume 19, Number 3—March 2013
Research
Effects of Vaccine Program against Pandemic Influenza A(H1N1) Virus, United States, 2009–2010
Table 3
Estimated number of cases of influenza prevented by vaccination against influenza A(H1N1)pdm09 virus*
Subgroup |
No. clinical cases in absence of vaccination program (range) |
No. clinical cases prevented by a vaccination program (range) |
No. doses administered to avoid 1 clinical case (range) |
6 mo–9 y | 12,333,906 (8,766,004–18,088,655) | 81,518 (52,081–100,349) | 326 (265–511) |
10–24 y (10–17 all, 18–24 NP) | 13,891,877 (9,879,008–20,374,801) | 300,724 (212,953–420,991) | 53 (38–75) |
Pregnant 18–64 y | 1,410,032 (1,004,978–2,062,896) | 71,601 (53,084–97,884) | 34 (25–45) |
25–64 y, HR, NP | 8,378,054 (5,957,746–12,286,626) | 164,958 (116,575–228,593) | 56 (40–79) |
25–64 y, HCW, non-HR, NP | 3,530,341 (2,510,291–5,178,995) | 123,427 (87,287–177,144) | 51 (35–72) |
25–64, contact with <6 mo, non-HCW, non-HR, NP | 1,550,007 (1,101,603–2,276,098) | 29,063 (19,904–43,129) | 70 (47–102) |
25–64 y, noncontact with <6 mo, non-HCW, non-HR, NP | 14,734,336 (10,470,235–21,640,930) | 163,327 (107,305–248,548) | 94 (62–143) |
>65 y |
6,038,353 (4,290,972–8,868,687) |
94,538 (63,719–142,293) |
114 (76–169) |
Total |
61,866,905 (43,980,837–90,777,687) |
1,029,157 (712,908–1,458,930) |
86 (61–124) |
*All values are estimates. NP, not pregnant; HR, high risk; HCW, health care worker; contact, household contacts and caregivers of children <6 mo of age. |
1Current affiliation: Merck & Co., Inc., Lansdale, Pennsylvania, USA.