Volume 19, Number 7—July 2013
Dispatch
Reducing Visceral Leishmaniasis by Insecticide Impregnation of Bed-Nets, Bangladesh
, M. Mamun Huda, Mithun Kumar Karmoker, Debashis Ghosh, Greg Matlashewski, Shah Golam Nabi, and Axel Kroeger
Table 1
VL incidence and affected households before and after bed-net impregnation program, Bangladesh, 2006–2010*
| Group | Bed-net impregnation |
Rate changes (p value) | % Reduction† compared with control (p value)‡ | |
|---|---|---|---|---|
| Before, no. (%) affected | After, no. (%) affected | |||
| HH§ | ||||
| Intervention, n = 2,512 | 40 (15.92) | 3 (1.19) | –14.73 (<0.0001) | –70.52% (0.0007) |
| Control, n = 3,143 | 21 (6.68) | 10 (3.18) | –3.50 (0.0476) | |
| Total, n = 5,655 |
61 (10.79) |
13 (2.30) |
–8.49 (<0.0001) |
|
| Population¶ | ||||
| Intervention, n = 11,426 | 43 (37.63) | 3 (2.63) | –35.01(<0.0001) | –66.49% (0.001) |
| Control, n = 14,021 | 26 (18.54) | 12 (8.56) | –9.99 (0.023) | |
| Total, n = 25,447 | 69 (27.12) | 15 (5.89) | –21.22 (<0.0001) | |
*VL, visceral leishmaniasis; HH, households.
†Effect of intervention: (B/A) – (D/C) Where A = baseline value for VL-affected HH per 1,000 HH/VL incidence per 10,000 persons in the intervention area; B = post-intervention value for VL-affected HH per 1,000 HH/VL incidence per 10,000 persons in the intervention area; C = baseline value for VL-affected HH per 1,000 HH/VL incidence per 10,000 persons in the control area; D = post-intervention value for VL-affected HH per 1,000 HHs/VL incidence per 10,000 persons in the control area. The effect is negative or positive if the VL-affected HH per 1,000 HHs/VL incidence per 10,000 persons is decreased or increased after intervention. Then the percentage reduction by intervention is calculated as (EI/[A]) × 100.
‡p values were calculated by Z statistic for pre- or post-rate differences between intervention and control areas.
§Incidence per 1,000 HH.
¶Incidence per 10,000 persons.