TableĀ 1

Results of screening contacts of all active patients with TB seen during 2015 at Northwick Park Hospital, London

Pulmonary TBExtrapulmonary TBAll patients
Number of active cases9198189
Mean age of active cases (SD)41.8 (SD 22.0)39.3 (SD 15.9)40.5 (SD 19.1)
Total number of screened contacts399299698
Mean number of screened contacts per index case (SD)4.4 (SD 6.3)3.1 (SD 2.3)3.7 (SD 4.7)
Number of contacts diagnosed with latent TB, N (%)108 (27.1)31 (10.4)139 (19.9)
Number of contacts diagnosed with active TB, N (%)8 (2)1 (0.3)9 (1.3)
Number of contacts treated for latent TB, N (%)83/108 (76.9)23/31 (74.2)106/139 (76.3)
Number of contacts who declined latent TB treatment, N (%)25/108 (23.1)8/31 (25.8)33/139 (23.7)
Number of contacts who failed to attend screening, N (%)41/399 (10.3)45/299 (15.1)86/698 (12.3)
Number of contacts whose outcome is not available, N (%)23/399 (5.8)7/299 (2.3)30/698 (4.3)