Table 3.

Tuberculosis estimates for risk groups per 100 000, NNS, contribution to tuberculosis epidemic and PAF

Risk group	Key population	Tuberculosis prevalence	Relative risk	NNS	Tuberculosis incidence	Estimated cases reported in 2016	PAF	Studies reviewed (n)
People with increased risk of tuberculosis bacilli infection due to occupational or community exposure	Healthcare workers	1400	1.9	71	1470	3397	3%	7
	Mineworkers	1300	3.8	77	3000	15 300	17%	5
	Inmates	3900	5.0	26	3900	6318	31%	5
	Informal settlements	3150	5.8	32	4500	148 500	43%	5
	Household tuberculosis contacts	4000	1.7	25	1300	20 468	1.7%	5
People with limited access to tuberculosis services	Children under 5 years	664	0.5	151	386	22 002	–	6
	Elderly	262	0.3	382	262	7860	–	1
	Migrants and refugees	36 000	4.2	3	3300	48 114	21%	1
	Women	230	0.3	435	230	63 563	–	1
People at increased risk of tuberculosis due to biological or behavioural factors that compromise immune function	HIV-infected	3000	5.4	33	4200	231 420	37%	5
	Diabetics	1240	1.6	81	1240	28 520	1.5%	1
	Pregnant women	2000	1.4	50	1080	12 960	0.8%	5
	Smokers	871	1.3	115	871	83 616	0.2%	1
	Chronic alcohol users	94913	1.4	105	949	78 767	0.4%	1

NNS, number needed to screen; PAF, population attributable fraction.