Table 1.

Univariable analysis of individual‐ and group‐level risk factors. Results of a univariable analysis of data collected from 1901 individuals in 73 social groups at the Kalahari Meerkat Project from 2002 to 2015, using time‐dependent Cox regression. Hazards were calculated for the likelihood of an individual meerkat being euthanased due to advanced tuberculosis (TB), and for an uninfected group to show its first case, using 3‐month time intervals

Variable	Hazard ratio	95% Confidence interval	Wald test P value
Individual risk
Year
2002–2005 baseline			0·09
2006–2010	3·30	0·52–20·82
2011–2015	0·55	0·04–8·14
Sex
Female			0·35
Male	1·18	0·84–1·66
Previous group TB
No			<0·0001
Yes	3·98	2·60–6·10
Dominant status
Never			0·42
Ever	0·86	0·59–1·25
Age (years)
<1			<0·0001
1	3·30	1·92–5·68
2	3·73	2·09–6·66
3	4·75	2·50–9·04
4	5·66	2·61–12·27
5	3·72	1·09–12·62
6+	2·66	0·91–7·84
Group risk
Dominance change
No			0·86
Yes	1·09	0·40–2·98
6‐month dominance change
No			0·42
Yes	0·68	0·26–1·74
12‐month dominance change
No			0·27
Yes	0·62	0·27–1·45
Group size
<10			0·66
11–20	1·25	0·45–3·46
21–30	0·91	0·24–3·49
>31	0·45	0·05–3·60
Rainfall
<200 mm			0·05
>200 mm	0·39	0·15–1·00
Immigration
No			0·19
Yes	2·09	0·70–6·26
6‐month immigration
No			0·11
Yes	2·23	0·84–5·96
12‐month immigration
No			0·01
Yes	3·13	1·29–7·58
Number of eligible rovers
0–4			0·83
5–9	1·03	0·41–2·59
10+	0·58	0·15–2·18
Number of eligible rovers in the preceding 12 months
0–4			0·79
5–9	1·42	0·52–3·88
10+	1·15	0·39–3·41
Year
2002–2005			0·13
2006–2010	1·32	0·35–4·93
2011–2015	2·69	0·82–8·82