Prevalence of Influenza A (H1N1) Seropositivity in Unvaccinated Healthcare Workers in Scotland at the Height of the Global Pandemic

Table 1

Seropositivity overall and by age band, separately for prepandemic and peak pandemic samples.

Age band (years)	Prepandemic samples				Peakpandemic samples
					Overall				Subdivided according to report of influenza-like symptoms
									Reporting symptoms			No symptoms reported
	Subgroup n	Seropositive n	% Seropositive		Subgroup n	Seropositive n	% Seropositive		Subgroup n	Seropositive n	% Seropositive	Subgroup n	Seropositive n	% Seropositive
16–25	46	2	4.3		46	8	17.4		21	3	14.3	25	5	20.0
26–35	128	10	7.8		129	15	11.6		65	10	15.4	64	5	7.8
36–45	138	10	7.2		137	14	10.2		52	7	13.5	85	7	8.2
46–55	114	4	3.5		125	8	6.4		47	2	4.3	78	6	7.7
56–65	45	5	11.1		56	6	10.7		23	3	13.0	33	3	9.1
Overall	471	31	6.6		493	51	10.3		208	25	12.0	285	26	9.1
95% CI			4.3 to 8.8				7.7 to 13.0				7.6 to 16.4			5.8 to 12.5