Background
Methods
Monitoring survivorship/Attrition
Monitoring integrity
Interview questionnaire
Data analysis
Survivorship
Study clearance
Results
Net survivorship/attrition
Water for washing nets | Kessounou (South) | Malanville (North) | Allada (South) | Kandi (North) | Total | |
---|---|---|---|---|---|---|
Near | Distant | |||||
Distance to water for washing LLINs | <0.05 km | <0.05 km | >5.0 km | >5.0 km | ||
Baseline (T0) | Households enrolled | 501 | 501 | 500 | 500 | 2002 |
After 6 months (T6) | Households eligible | 501 | 501 | 500 | 500 | 2002 |
Households visited/opened | 493 | 455 | 420 | 451 | 1819 | |
Coded LLINs found | 444 | 424 | 374 | 430 | 1672 | |
(LLINs lost) | (49) | (31) | (46) | (21) | (147) | |
Survivorship (%) | 90 | 94 | 91 | 96 | 93 | |
After 12 months (T12) | Households eligible | 452 | 470 | 454 | 479 | 1855 |
Households visited/opened | 393 | 411 | 396 | 442 | 1642 | |
Coded LLINs found | 253 | 338 | 286 | 348 | 1225 | |
(LLINs lost) | (140) | (73) | (110) | (94) | (417) | |
Survivorship (%) | 62 | 79 | 69 | 77 | 72 | |
95% confidence interval | 58.20-66.70 | 75.80-82.90 | 64.90-73.00 | 73.40-80.80 | 69.90-73.80 | |
After 18 months (T18) | Households eligible | 312 | 397 | 344 | 385 | 1438 |
Households visited/opened | 293 | 350 | 274 | 345 | 1262 | |
Coded LLINs found | 227 | 279 | 184 | 283 | 973 | |
(LLINs lost) | (66) | (71) | (90) | (62) | (289) | |
Survivorship (%) | 49 | 65 | 51 | 65 | 57 | |
95% confidence interval | 44.90-53.70 | 62.90-71.10 | 46.60-55.40 | 58.70-67.20 | 55.30-59.60 |
Reasons for net loss
Kessounou (South) | Malanville (North) | Allada (South) | Kandi (North) | Total | ||
---|---|---|---|---|---|---|
After 6 months (T6) | (LLINs lost) | (49) | (31) | (46) | (21) | (147) |
‘physical damage’ responses | 10 | 3 | 5 | 1 | 19 | |
‘removal’ responses | 35 | 28 | 41 | 20 | 124 | |
‘re-purposed’ responses | 4 | 0 | 0 | 0 | 4 | |
After 12 months (T12) | (LLINs lost) | (140) | (73) | (110) | (94) | (417) |
Questionnaires administered | 140 | 73 | 110 | 94 | 417 | |
‘physical damage’ responses | 79 | 19 | 13 | 7 | 118 | |
‘removal” resonses | 34 | 49 | 85 | 72 | 240 | |
‘re-purposed’ responses | 27 | 05 | 12 | 15 | 59 | |
Attrition rate-1 (%) | 18 | 05 | 04 | 02 | 07 | |
95% confidence interval | 14.67-21-35 | 02.92-06.56 | 02.29-05.62 | 00.81-03.13 | 05.82-08.03 | |
Attrition rate-2 | 14 | 15 | 25 | 18 | 18 | |
95% confidence interval | 11.03-17.07 | 12.48-18.79 | 21.59-29.18 | 15.25-22.03 | 16.55-19.93 | |
Attrition rate-3 | 06 | 01 | 02 | 03 | 03 | |
95% confidence interval | 04.-39-08.65 | 00.43-02.31 | 01.38-04.15 | 01.83-04.89 | 02.47-04.01 | |
% net loss (total attrition) | 38 | 21 | 31 | 23 | 28 | |
After 18 months (T18) | (LLINs lost) | (66) | (71) | (90) | (62) | (289) |
Questionnaires administered | 66 | 71 | 90 | 62 | 289 | |
‘physical damage’ responses | 38 | 36 | 31 | 27 | 132 | |
‘removal’ responses | 26 | 34 | 59 | 35 | 154 | |
‘re-purposed’ responses | 2 | 1 | 0 | 0 | 3 | |
Attrition rate-1 | 25 | 12 | 10 | 07 | 14 | |
95% confidence interval | 21.74-29.34 | 09.06-14.68 | 07.49-12.72 | 05.08-09.58 | 12.01-15.00 | |
Attrition rate-2 | 19 | 22 | 37 | 25 | 26 | |
95% confidence interval | 15.77-22.63 | 18.74-26.00 | 32.88-41.32 | 21.78-29.39 | 24.00-27.84 | |
Attrition rate-3 | 07 | 01 | 02 | 03 | 03 | |
95% confidence interval | 04.73-09.11 | 00.55-02.59 | 01.38-04.15 | 01.83-04.89 | 02.60-04.17 | |
% net loss (total attrition) | 51 | 35 | 49 | 35 | 43 |
LLIN fabric integrity
Kessounou South | Malanville North | Allada South | Kandi North | |||||
---|---|---|---|---|---|---|---|---|
T12 | T18 | T12 | T18 | T12 | T18 | T12 | T18 | |
Tagged LLINs found | 253 | 227 | 338 | 279 | 286 | 184 | 348 | 283 |
n (%) of nets found with any hole (s) | 219 (87) | 210 (92) | 294 (87) | 260 (93) | 178 (62) | 133 (72) | 241 (69) | 208 (73) |
CI95 of (%) | 81.73-90.51 | 88.28-95.58 | 82.92-90.38 | 89.57-95.85 | 56.34-67.88 | 65.22-78.62 | 64.11-74.06 | 67.95-78.55 |
Mean pHI | 799 | 1479 | 691 | 888 | 398 | 623 | 510 | 447 |
Median pHI | 290 | 706 | 243 | 312 | 46 | 105 | 86 | 96 |
IQR pHI | 1034 | 2057 | 978 | 1156 | 439 | 667 | 560 | 477 |
n (%) of nets in pHI<64 ‘good’ catagory | 69 (27) | 43 (19) | 107(32) | 73 (26) | 162 (57) | 83 (46) | 161 (46) | 133 (47) |
CI95 (%) | 22.16-33.07 | 14.38-24.54 | 26.93-36.80 | 21.36-31.62 | 50.8-62.26 | 39.2-53.67 | 41.10-51.52 | 41.26-52.81 |
n (%) of nets in 64<pHI<768 ‘serviceable’ catagory | 100 (40) | 74 (33) | 129 (38) | 105 (38) | 79 (28) | 53 (30) | 112(32) | 99 (35) |
CI95
| 33.70-45.66 | 26.83-38.94 | 33.15-43.45 | 32.1-43.45 | 22.76-33.08 | 23.4-36.67 | 27.49-37.26 | 29.66-40.71 |
n (%) of nets in pHI >768 ‘needs replacement’ catagory | 84 (33) | 110 (48) | 102 (30) | 101 (36) | 45 (16) | 43 (24) | 75 (22) | 51 (18) |
CI95
| 27.69-39.22 | 42.04-54.93 | 25.53-35.27 | 30.7-41.27 | 11.9-20.40 | 18.3-30.78 | 17.5-26.17 | 13.98-22.92 |
Kessounou South | Malanville North | Allada South | Kandi North | |||||
---|---|---|---|---|---|---|---|---|
Distance to water for washing nets | < 0.05 km | > 5.0 km | ||||||
Assessment visit | T12 | T18 | T12 | T18 | T12 | T18 | T12 | T18 |
n of nets found with any hole (s) | 219 | 210 | 294 | 260 | 178 | 133 | 241 | 208 |
n (%) of nets with ‘rip in the fabric’ | 158 (72) | 142 (68) | 279 (95) | 248 (95) | 133 (75) | 114 (86) | 219 (91) | 178 (86) |
CI 95% | 65.87-77.66 | 61.02-73.58 | 91.75-96.88 | 92.11-97.34 | 67.86-80.54 | 78.76-90.66 | 86.57-93.89 | 80.16-89.71 |
n (%) of nets with ‘rip in the seam’ | 4 (2) | 5 (2) | 3 (1) | 5 (2) | 10 (6) | 3 (2) | 9 (4) | 16 (8) |
CI 95% | 00.71-04.60 | 01.02-05.45 | 00.35-02.96 | 00.82-04.42 | 03.08-10.03 | 00.77-06.42 | 01.98-06.94 | 04.79-12.13 |
n (%) of nets with ‘burn holes’ | 52 (24) | 62 (29) | 9 (3) | 6 (2) | 26 (14) | 11 (8) | 12 (5) | 9 (4) |
CI 95% | 18.59-29.80 | 23.77-36.02 | 01.62-05.71 | 01.06-04.94 | 10.17-20.54 | 04.68-14.20 | 02.87-08.50 | 02.29-08.02 |
n (%) of nets chewing by rodent | 5 (2) | 2 (1) | 3 (1) | 1 (1) | 9 (5) | 5 (4) | 1 (0) | 5 (2) |
CI 95% | 00.98-05.23 | 00.26-03.41 | 00.35-02.96 | 00.07-02.15 | 02.68-09.33 | 01.62-08.50 | 00.07-02.31 | 01.03-05.50 |
Factors associated with loss of integrity
Factors | Modalities | KESSOUNOU | MALANVILLE | ALLADA | KANDI | ||||
---|---|---|---|---|---|---|---|---|---|
T12 | T18 | T12 | T18 | T12 | T18 | T12 | T18 | ||
Washing frequency
| None | 08.16 | 02.17 | 04.00 | 00.00 | 28.00 | 31.91 | 14.29 | 22.45 |
1 time | 04.08 | 02.17 | 06.00 | 06.12 | 30.00 | 10.64 | 16.33 | 12.24 | |
2-5 times | 61.22 | 36.96 | 52.00 | 24.49 | 38.00 | 44.68 | 63.27 | 48.98 | |
6-10 times | 16.33 | 39.13 | 24.00 | 34.69 | 04.00 | 12.77 | 06.12 | 16.33 | |
10 and more | 10.20 | 19.57 | 14.00 | 34.69 | 00.00 | 00.00 | 00.00 | 00.00 | |
LLINs maintenance
| Clean | 30.61 | 41.30 | 46.00 | 26.53 | 28.00 | 25.53 | 36.73 | 28.57 |
Dirty | 69.39 | 58.70 | 54.00 | 73.47 | 72.00 | 74.47 | 63.27 | 71.43 | |
LLINs use
| Not at all | 04.08 | 04.35 | 00.00 | 06.12 | 08.00 | 00.00 | 02.04 | 2.04 |
Often | 26.53 | 30.43 | 16.00 | 34.69 | 22.00 | 25.53 | 16.33 | 42.86 | |
Every night | 69.39 | 65.22 | 84.00 | 57.14 | 70.00 | 74.47 | 81.63 | 55.10 | |
Roofing material
| Paving stone | 2.04 | 02.17 | 02.00 | 01.15 | 02.00 | 02.13 | 01.00 | 02.04 |
Straw | 20.41 | 34.78 | 22.00 | 21.30 | 00.00 | 00.00 | 06.12 | 02.04 | |
Steel sheet | 77.55 | 63.04 | 76.00 | 77.55 | 98.0 | 97.87 | 92.88 | 95.92 | |
Daytime location of LLIN
| Hanging | 71.43 | 71.74 | 74.00 | 59.18 | 64.00 | 80.85 | 81.63 | 71.43 |
Folded | 22.45 | 23.91 | 26.00 | 36.73 | 20.00 | 14.89 | 16.33 | 28.57 | |
Tidy away | 6.12 | 04.35 | 00.00 | 04.08 | 16.00 | 04.26 | 02.04 | 00.00 | |
Location of the kitchen
| Outside | 83.67 | 76.52 | 90.00 | 100.0 | 96.00 | 93.62 | 97.96 | 100.0 |
Inside | 16.33 | 23.48 | 10.00 | 00.00 | 04.00 | 06.38 | 02.04 | 00.00 | |
Cooking fuel
| Firewood | 97.96 | 97.83 | 90.00 | 97.96 | 62.00 | 68.09 | 67.35 | 87.76 |
Chacoral | 02.04 | 02.17 | 08.00 | 02.04 | 36.00 | 29.79 | 30.61 | 10.20 | |
Gas | 00.00 | 00.00 | 02.00 | 00.00 | 02.00 | 00.00 | 02.04 | 02.04 | |
kerosene | 0.00 | 00.00 | 0.00 | 00.00 | 0.00 | 02.13 | 0.00 | 00.00 | |
Sleeping material
| Other | 0.00 | 00.00 | 8.00 | 12.24 | 4.00 | 02.13 | 20.41 | 10.20 |
Bed | 4.08 | 08.70 | 42.00 | 30.61 | 44.00 | 48.94 | 51.02 | 51.02 | |
Matting | 95.92 | 91.30 | 50.00 | 57.14 | 52.00 | 48.94 | 28.57 | 38.78 | |
Total number of households visited/opened
| 393 | 293 | 411 | 350 | 396 | 274 | 442 | 345 |
Factors | Modalities | Coefficients | Rate ratio | CI-% (RR) | P (Wald test) | P (LR-test) |
---|---|---|---|---|---|---|
Washing frequency
| None | - | 1.00 | - | - | <0.0001 |
1 | 0.744 | 2.1 | [0.92-04.84] | 0.07967 | ||
2-5 | 1.024 | 2.78 | [1.40-05.55] | 0.00355 | ||
>=6 | 1.766 | 5.85 | [2.85-11.99] | <0.0001 | ||
Type of roof
| Steel sheet | - | 1.00 | - | - | 0.168491 |
Straw | −0.324 | 0.72 | [0.46-01.15] | 0.16930 | ||
Location of kitchen in the house
| Outside | - | 1.00 | - | - | 0.026399 |
Inside | 0.543 | 1.72 | [1.06-02.79] | 0.027699 | ||
Cooking fuel
| Charcoal | - | 1.00 | - | - | 0.034210 |
Firewood | 0.582 | 1.79 | [1.04-03.09] | 0.036875 | ||
Sleeping material
| Other | - | 1.00 | - | - | 0.774194 |
Bed | −0.229 | 0.79 | [0.43-01.49] | 0.472834 | ||
Matting | −0.142 | 0.87 | [0.48-01.56] | 0.6365219 | ||
LLINs maintenance
| High | - | 1.00 | - | - | 0.002677 |
Low | 0.526 | 1.69 | [1.20-02.39] | 0.002908 | ||
Frequency of net use
| Not at all | - | 1.00 | - | - | 0.077341 |
Often | −0.889 | 0.41 | [0.19-00.88] | 0.02139 | ||
Every night | −0.718 | 0.49 | [0.24-01.00] | 0.05074 | ||
Distance to water for washing
| >5 km | - | 1 | - | - | 0.000106 |
<0.5 km | 0.48 | 1.61 | [1.27-2.05] | 0.000106 | ||
Number of sleeper/Net
| - | 0.105 | 1.11 | [0.96-01.28] | 0.14466 | 0.153694 |