Table 1.

Effect of BCG vaccination of UK teenagers on IFN-γ responses to mycobacterial and control antigens. n= 148 (control group n = 62, vaccine group n = 86) except Ag85 where n= 43 (baseline), 50 (3 months), 49 (12 months).

		Time after vaccination
		Baseline		3 months		12 months
Antigen		Control	Vaccinated	Control	Vaccinated	Control	Vaccinated
M.tb PPD	% responders	23	19	31	87	19	74
	Median pg/ml (IQ range)	0 (0–60)	0 (0–36)	0 (0–103)	488 (150–1178)	0 (0–46)	214 (57–822)
p value Vaccinated versus Control		0.5		< 0.001		< 0.001
M.tb Ag85	% responders	78	72	90	100	62	96
	Median pg/ml (IQ range)	184 (61–721)	168 (45–426)	813 (221–1340)	1192 (865–2353)	112 (0–262)	808 (386–1865)
p value Vaccinated versus Control		0.67		0.09		0.002
RPMI	% responders	5	7	8	6	3	6
	Median pg/ml (IQ range)	15 (15)	15 (15)	15 (15)	15 (15)	15 (15)	15 (15)
PHA	% responders	97	100	98	97	87	86
	Median pg/ml (IQ range)	2940 (1432–3692)	3200 (2225–4700)	3807 (1496–4529)	3578 (2610–4092)	2578 (314–3357)	2797 (548–4202)
p value Vaccinated versus Control		0.09		0.76		0.85