. 2011 Mar 22;173(10):1121–1130. doi: 10.1093/aje/kwq497

Table 1.

Observed and Simulated Age-Specific Fractions (%) Infected With Pandemic Influenza A (H1N1) in Pittsburgh, Pennsylvania; Los Angeles County, California; and the continental United States, 2009

Age Group, years	Observed Seroprevalence^a	Simulated Seroprevalence
Age Group, years	Observed Seroprevalence^a	Los Angeles County	Continental United States
0–4	28	21	22
5–18	39	44	45
19–29	22	16	18
30–64	18	18	20
≥65	13	14	16
Total	22	23	25

Data were from samples taken from hospitals and clinics in Pittsburgh, Pennsylvania, from mid-November to early December 2009 (16).