Prevalence of Trachoma in 47 Administrative Districts of Zambia: Results of 32 Population-Based Prevalence Surveys

Figures & data

Figure 1. Trachoma prevalence surveys undertaken in Zambia, 2012, using either the integrated threshold mapping (ITM) methodology, or a population-based prevalence survey (PBPS) approach. Key to districts: 1. Chibombo; 2. Chisamba; 3. Chitambo; 4. Itezhi tezhi; 5. Kabwe Rural; 6. Kapiri Mposhi; 7. Luano; 8. Mkushi; 9. Mumbwa; 10. Ngabwe; 11. Serenje; 12. Chililbombwe; 13. Chingola; 14. Kalulushi; 15. Kitwe; 16. Luanshya; 17. Lufwanyama; 18. Masaiti; 19. Mpongwe; 20. Mufulira; 21. Ndola; 22. Chadiza; 23. Chipata; 24. Katete; 25. Lundazi; 26. Mambwe; 27. Nyimba; 28. Petauke; 29. Sinda; 30. Vubwi; 31. Chembe; 32. Chienge; 33. Chipili; 34. Kawambwa; 35. Lunga; 36. Mansa; 37. Milenge; 38. Mwansabombwe; 39. Mwense; 40. Nchelenge; 41. Samfya; 42. Chilanga; 43. Chirundu; 44. Chongwe; 45. Kafue; 46. Luangwa; 47. Lusaka; 48. Rufunsa; 49. Shibuyunji; 50. Chama; 51. Chinsali; 52. Isoka; 53. Mafinga; 54. Mpika; 55. Nakonde; 56. Shiwangandu; 57. Chavuma; 58. Ikelenge; 59. Kabompo; 60. Kasempa; 61. Manyinga; 62. Mufumbwe; 63. Mwinilunga; 64. Solwezi; 65. Zambezi; 66. Chilubi; 67. Kaputa; 68. Kasama; 69. Luwingu; 70. Mbala; 71. Mporokoso; 72. Mpulungu; 73. Mungwi; 74. Nsama; 75. Chikankata; 76. Choma; 77. Gwembe; 78. Kalomo; 79. Kazungula; 80. Livingstone; 81. Mazabuka; 82. Monze; 83. Namwala; 84. Pemba; 85. Siavonga; 86. Sinazongwe; 87. Zimba; 88. Kalabo; 89. Kaoma; 90. Limulunga; 91. Luampa; 92. Lukulu; 93. Mitete; 94. Mongu 95. Mulobezi; 96. Mwandi; 97. Nalolo; 98. Nkeyema; 99. Senanga; 100. Sesheke; 101. Shang’ombo; 102. Sikongo; 103. Sioma.

Table 1. Number of ≥15-year-olds and number of 1–9-year-olds resident, examined, absent and refused in selected households; prevalence of all trichiasis; prevalence of all trichiasis unknown to the health system; prevalence of trichiasis+TS unknown to the health system; and prevalence of trachomatous inflammation—follicular (TF); by evaluation unit, trachoma prevalence surveys, Zambia, 2016–2017, with comparison to prevalence estimates from previous surveys, where available.

				2016–2017 (current) survey data
		2008–2012 survey data		≥15-year-olds							1–9-year-olds
Province	Districts included in evaluation unit [district label in Figure 1–3] (estimated evaluation unit population in 2017)	TF prevalence^e, %	Trichiasis prevalence^c, %	Resident	Examined	Absent	Refused	Prevalence of all trichiasis, %^a (95% CI) [NOC]	Prevalence of all trichiasis UTTHS, %^a (95% CI) [NOC]	Prevalence of trichiasis+TS UTTHS, %^a (95% CI) [NOC]	Resident	Examined	Absent	Refused	TF prevalence, %^b (95% CI)
Luapula	Chembe [31], Mansa [36] (209,090)	C: ND; M: 10.5^d	C: ND; M: 1.7^d	1598	1469	118	11	0.02 (0.00–0.05) [2]	0.02 (0.00–0.05) [2]	0.02 (0.00–0.05) [2]	1,318	1,287	30	1	3.8 (1.5–6.6)
	Mwansabombwe [38], Kawambwa [34] (156,662)	M: ND; K: 7.3^d	M: ND; K: 0.7^d	1736	1609	123	4	0.13 (0.02–0.26) [5]	0.07 (0.00–0.18) [2]	0.05 (0.00–0.16) [1]	1,337	1,310	27	0	1.1 (0.4–1.9)
	Milenge [37], Samfya [41], Lunga [35] (275,242)	M: 16.4^d; S: 7.9^d; L: ND	M: 0.8^d; S: 0.5^d; L: ND	1689	1573	109	7	0.07 (0.01–0.13) [5]	0.05 (0.01–0.09) [4]	0.05 (0.01–0.09) [4]	1,377	1,347	30	0	3.7 (2.3–5.4)
Central	Itezhi tezhi [4], Mumbwa [9] (260,188)	I: 35.8^d; M: 4.0	I: 0.5^d; M: 0.0^d	1973	1830	137	6	0.14 (0.05–0.28) [7]	0.09 (0.01–0.21) [5]	0.09 (0.01–0.21) [5]	1,408	1,355	48	5	4.7 (2.0–7.1)
	Kapiri Mposhi [6] (253,706)	13.3^d	6.9^d	1568	1,414	139	13	0.20 (0.06–0.40) [10]	0.12 (0.02–0.26) [7]	0.09 (0.00–0.22) [5]	1,105	1,067	35	3	5.6 (2.8–9.2)
	Mkushi [8] (155,534)	4.0^d	0.0^d	1493	1378	109	5	0.07 (0.00–0.17) [3]	0.05 (0.00–0.13) [2]	0.03 (0.00–0.09) [1]	1,243	1,223	16	4	6.8 (3.6–11.6)
	Kabwe Rural [5] (199,042)	7.2^d	1.2^d	1313	1170	143	0	0.07 (0.00–0.12) [3]	0.07 (0.00–0.12) [3]	0.07 (0.00–0.12) [3]	808	789	19	0	1.2 (0.5–2.0)
	Serenje [11], Chitambo [3] (274,434)	15.3^d	0.5^d	1590	1434	147	9	0.01 (0.00–0.04) [1]	0.00 (0.00–0.00) [0]	0.00 (0.00–0.00) [0]	1,263	1,230	33	0	4.1 (1.5–6.6)
Lusaka	Kafue [45] (137,883)	7.1^d	0.0^d	1646	1517	128	1	0.08 (0.00–0.25) [2]	0.08 (0.00–0.23) [1]	0.08 (0.00–0.23) [1]	1,045	1,009	36	0	1.8 (1.0–3.0)
Muchinga	Chama [50] (125,670)	15.5^d	4.5^d	1263	1178	76	7	0.79 (0.34–1.36) [15]	0.48 (0.17–0.85) [11]	0.30 (0.05–0.64) [7]	975	954	20	1	4.7 (1.7–9.1)
	Nakonde [55] (98,867)	0.8^d	0.7	1564	1435	126	3	0.23 (0.06–0.51) [8]	0.20 (0.03–0.47) [6]	0.02 (0.00–0.04) [2]	1,045	1,010	35	0	3.8 (1.5–6.6)
	Isoka [52], Mafinga [53] (149,372)	I: 20.0^d; M: ND	I: 1.8^d; M: ND	1584	1474	104	6	0.08 (0.00–0.21) [4]	0.08 (0.00–0.21) [4]	0.05 (0.00–0.16) [3]	1,109	1,080	28	1	2.1 (0.5–3.4)
	Chinsali [51], Shiwangandu [56] (149,664)	C: 28.5^d; S: ND	C: 0.6^d; S: ND	1500	1371	120	8	0.28 (0.08–0.57) [7]	0.15 (0.04–0.31) [4]	0.11 (0.00–0.26) [3]	1,119	1,074	45	0	5.0 (2.5–8.4)
	Mpika [54] (19,436)	9.7^e	0.3^e	1446	1297	143	6	0.39 (0.07–0.81) [10]	0.23 (0.04–0.51) [7]	0.21 (0.02–0.51) [6]	1,105	1,064	38	3	3.8 (1.5–6.6)
Eastern	Chadiza [22], Vubwi [30] (111,646)	C: 14.4^d; V: ND	C: 0.5^d; V: ND	1461	1363	95	3	0.09 (0.00–0.16) [4]	0.09 (0.00–0.16) [4]	0.03 (0.00–0.08) [1]	1,098	1,060	36	2	1.9 (0.6–4.1)
	Lundazi [25] (354,689)	16.0^d	3.7^d	1494	1382	109	3	0.13 (0.01–0.29) [4]	0.07 (0.00–0.20) [2]	0.07 (0.00–0.21) [2]	1,152	1,120	31	1	4.2 (2.5–6.3)
	Katete [24], Mambwe [26] (284,899)	K: 0.5^d; M: 8.2^d	K: 0.2^d; M: 1.5^d	1696	1518	176	2	0.26 (0.03–0.61) [6]	0.21 (0.01–0.57) [5]	0.21 (0.01–0.55) [5]	899	868	30	1	0.1 (0.0–0.4)
Western	Mulobezi [95], Mwandi [96], Sesheke [100] (118,491)	M: ND; M: ND; S: 4.7^d	M: ND; M: ND; S: 0.0	1482	1408	73	0	0.28 (0.11–0.50) [15]	0.21 (0.05–0.44) [11]	0.16 (0.02–0.37) [9]	1,107	1,090	15	2	7.7 (4.1–11.7)
	Nalolo [97], Senanga [99] (110,395)	N: ND; S: 7.4^d	N: ND; S: 0.0^d	1485	1431	51	3	0.45 (0.15–0.90) [12]	0.43 (0.13–0.88) [11]	0.37 (0.08–0.82) [9]	1,074	1,050	23	0	13.4 (9.7–17.3)
Northern	Chilubi [66] (77,804)	15.6^d	0.7^d	1510	1392	109	9	0.28 (0.02–0.47) [7]	0.28 (0.02–0.46) [7]	0.27 (0.00–0.47) [6]	1,333	1,300	31	2	10.4 (6.9–14.3)
	Kaputa [67], Nsama [74] (119,514)	K: 19.6^d; N: ND	K: 1.7^d; N: ND	1516	1450	55	10	0.17 (0.03–0.30) [6]	0.15 (0.00–0.27) [5]	0.15 (0.00–0.27) [5]	1,293	1,261	32	0	5.6 (3.2–8.9)
	Kasama [68] (127,441)	11.4^d	2.8^d	1466	1323	137	6	0.33 (0.08–0.56) [13]	0.14 (0.05–0.27) [9]	0.13 (0.04–0.26) [8]	1,075	1,045	29	1	5.7 (2.4–9.1)
	Luwingu [69] (114,258)	10.1^d	1.6^d	1604	1434	159	11	0.16 (0.03–0.36) [7]	0.13 (0.02–0.31) [5]	0.11 (0.00–0.29) [4]	1,242	1,221	20	1	5.2 (1.9–9.8)
	Mbala [70] (75,475)	3.2^d	0.9^d	1550	1433	112	5	0.13 (0.03–0.24) [5]	0.13 (0.03–0.24) [5]	0.13 (0.03–0.23) [5]	1,071	1,041	28	2	2.5 (1.1–4.1)
	Mporokoso [71] (95,842)	18.7^d	2.4^d	1500	1377	117	6	0.13 (0.05–0.23) [8]	0.09 (0.02–0.18) [5]	0.09 (0.02–0.18) [5]	1,167	1,134	33	0	5.4 (2.8–7.3)
	Mpulungu [72] (98,043)	4.2^d	1.8	1574	1442	125	7	0.55 (0.04–1.45) [7]	0.13 (0.01–0.34) [5]	0.13 (0.01–0.34) [5]	1,158	1,120	37	1	4.7 (2.7–7.0)
	Mungwi [73] (151,058)	16.5^d	2.3^d	1463	1342	111	10	0.45 (0.20–0.71) [14]	0.35 (0.12–0.59) [10]	0.28 (0.08–0.49) [8]	1,124	1,097	26	1	8.6 (5.0–12.2)
Copperbelt	Chililbombwe [12] (79,326)	17.8^d	0.0^d	1718	1513	193	11	0.01 (0.00–0.02) [1]	0.01 (0.00–0.02) [1]	0.01 (0.00–0.02) [1]	980	906	70	4	0.6 (0.2–1.2)
	Chingola [13] (216,626)	13.7^d	0.0^d	1785	1524	240	21	0.08 (0.00–0.16) [2]	0.04 (0.00–0.12) [1]	0.04 (0.00–0.12) [1]	1,038	959	71	8	0.7 (0.3–1.4)
	Kalulushi [14] (100,381)	14.6^d	0.0^d	1591	1328	243	19	0.06 (0.00–0.17) [3]	0.03 (0.00–0.09) [2]	0.00 (0.00–0.00) [0]	965	922	42	1	1.7 (0.4–3.5)
	Luanshya [16] (152,933)	13.6^d	0.0^d	1523	1364	146	13	0.16 (0.00–0.40) [4]	0.15 (0.00–0.39) [3]	0.10 (0.00–0.25) [2]	856	813	35	8	1.0 (0.3–1.9)
	Lufwanyama [17], Mpongwe [19] (171,883)	L: 11.0^d; M: 10.1^d	L: 0.0^d; M: 0.0^d	1145	1075	55	14	0.14 (0.00–0.39) [2]	0.14 (0.00–0.38) [2]	0.14 (0.00–0.38) [2]	831	807	18	6	1.7 (0.6–3.6)

^aAdjusted for gender and age in 5-year age bands (see text).

^bAdjusted for age in 1-year age bands (see text).

^cSingle letters are used in this column to abbreviate the names of administrative districts shown in the column headed “Evaluation unit”, where administrative district-level surveys (as opposed to surveys covering the whole of the evaluation unit) were previously undertaken

^d2012 estimate.

^e2008 estimate.

CI, confidence interval; ND, no data; NOC, number of cases; TS, trachomatous scarring; UTTHS, unknown to the health system.

Figure 2. Prevalence of trichiasis + trachomatous scarring (TS) unknown to the health system (UTTHS), in ≥15-year-olds, by evaluation unit, trachoma prevalence surveys, Zambia, 2016–2017.

Figure 3. Prevalence of trachomatous inflammation—follicular (TF) in 1–9-year-olds, by evaluation unit, trachoma prevalence surveys, Zambia, 2016–2017.