Table 3.

Prevalence of trachomatous inflammation—follicular (TF) and trichiasis or trachomatous trichiasis (TT) at baseline and impact surveys, 15 local government areas of Kebbi, Sokoto and Zamfara States, Nigeria.

			Baseline survey data						Impact survey data
State	Local government area	Population	Year	Trichiasisa prevalence in ≥15-year-olds, % [95% confidence interval]	Estimated TT backlog	TF prevalence in 1-9-year-olds, % [95% confidence interval]	Number of people operated for TT	Rounds of MDA	Year	TT prevalence in ≥15-year-olds, % [95% confidence interval]	TF prevalence in 1-9-year-olds (%) [95% confidence interval]
Kebbi	Argungu	200,248	2004	1.8 [0.5–3.1]	2018	16.3 [12.6–20.0]	2415	3	2014	0.05 [0.00–0.14]	2.8 [1.7–4.3]
	Augie	116,368	2004	0.9 [0–1.8]	586	21.3 [17.1–25.5]	1675	3	2014	0.26 [0.07–0.48]	6.7 [4.1–10.0]
	Arewa	198,728	2004	1.0 [0.1–1.9]	1113	13.6 [10.2–17.0]	2390	3	2014	0.77 [0.51–1.10]	4.3 [3.3–5.4]
Sokoto	Gada	249,051	2004	3.1 [1.6–4.6]	4324	29.1 [24.7–33.5]	1632	3	2016	0.1 [0.0–0.3]	9.7 [6.5–13.5]
	Gwadabawa	231,569	2006	4.0 [2.5–6.3]	5187	49 [42.9–55.1]	927	5	2014	0.03 [0.00–0.08]	4.2 [2.2–7.1]
	Kware	134,084	2006	5.6 [3.2–8.0]	4205	43 [36.9–49.1]	666	1	2014	0.3 [0.1–0.4]	2.2 [0.7–2.9]
	Binji	104,274	2006	2.1 [0.6–3.6]	1226	29 [23.4–3.6]	413	3	2016	0.4 [0.0–0.9]	5.9 [4.1–7.9]
	Goronyo	182,118	2004	5.9 [3.8–8.0]	6017	26.8 [22.5–31.1]	1290	3	2016	0.03 [0.0–0.1]	7 [4.8–9.1]
	Illela	150,133	2004	3.1 [1.6–4.6]	2606	29.7 [25.4–34.0]	1309	3	2016	0.04 [0.0–0.09]	10.3 [7.2–14.3]
	Isa	150,268	2004	2.9 [1.5–4.3]	2440	13.5 [10.2–16.8]	2163	3	2016	0.04 [0.0–0.12]	5.4 [3.7–7.7]
	Rabah	149,152	2004	2.8 [1.4–4.2]	2339	21.4 [17.5–25.3]	1339	3	2016	0	3.8 [1.5–5.7]
	Tangaza	114,770	2004	2.7 [1.3–4.1]	1735	21.4 [17.5–25.4]	1431	3	2016	0.1 [0.0–0.28]	6.5 [4.3–9.3]
Zamfara	Birnin Magajib	184,083	2004	1.4 [0.4–2.4]	1443	32.1 [27.6–36.6]	696	4	2016	0.22 [0.07–0.43]	1.7 [1.1–2.3]
	Shinkafi	135,964	2004	1.2 [0.25–2.15]	914	17.9 [14.1–21.6]	803	3	2015	0.01 [0.00–0.04]	1.4 [0.5–2.9]
	Zurmi	293,977	2004	1.1 [0.2–1.9]	1811	22.7 [18.7–26.7]	711	3	2015	0.18 [0.03–0.38]	1.2 [0.6–2.1]

^aBaseline surveys were conducted by other investigators; for many of these surveys, fieldwork and analysis protocols could not be located. Baseline survey data have been provided as reported, and only as a comparator for our impact survey data. We assume, based on then-current practice that the presence of TS was not required for “trachomatous trichiasis” to be diagnosed at baseline, even though the survey reports refer to prevalence estimates of “trachomatous trichiasis”.

^bSecond impact survey (2016).