Impact of insecticide treated mosquito nets and low dose monthly diethylcarbamazine on lymphatic filariasis infection between 1999 and 2004 in two endemic communities of north-eastern Tanzania

TY - JOUR

T1 - Impact of insecticide treated mosquito nets and low dose monthly diethylcarbamazine on lymphatic filariasis infection between 1999 and 2004 in two endemic communities of north-eastern Tanzania

AU - Lemnge, Martha M.

AU - Mmbando, Bruno P.

AU - Segeja, Method D.

AU - Gesase, Samwel

AU - Bygbjerg, Ib C.

PY - 2012/11/5

Y1 - 2012/11/5

N2 - Lymphatic filariasis (LF) is among the poverty related neglected tropical diseases earmarked for elimination using mass drug administration (MDA) strategy. Additional use of insecticide treated mosquito nets (ITNs) might enhance elimination of LF infection. Between August 1998 and July 1999, all individuals aged ≥ 8 months from Magoda and Mpapayu villages in northeastern Tanzania, were administered with monthly low dose diethylcarbamazine (DEC) at a dosage of 50mg in children aged < 15 years and 100mg in adults aged ≥ 15 years. ITNs were also distributed to Magoda in December 1998 and to Mpapayu in March 2001. The main objective of our study was to assess the impact of ITNs and low dose DEC on microfilaria (mf) prevalence and intensity and incidence of new mf infections. Four annual cross-sectional surveys were conducted between 1999 and 2004 in the two villages to screen for Wuchereria bancrofti microfilariae in individuals aged ≥ 1 year. Overall, 80% of the population in Magoda and 66% in Mpapayu were covered during these surveys. Results revealed a significant decrease in both mf prevalence and intensity in both villages. Furthermore, there was a steady decrease in mf incidence in Magoda; with 36.7 cases per 1000 person years in 2000 and 7.4 in 2004. In Mpapayu, the incidence initially increased from 20.8 cases in 2000 to 24.3 in 2001 and then decreased to 7.2 cases in 2004. Individuals using ITNs in Magoda had significantly lower risk of mf (OR=0.681; 95%CI: 0.496-0.934); and the risk of new infections was reduced by 58.8% (95%CI: 30.3-75.4). These results suggest that when MDA is complemented with ITNs there is high likelihood to half filariasis transmission within a shorter period than using chemotherapy alone.

AB - Lymphatic filariasis (LF) is among the poverty related neglected tropical diseases earmarked for elimination using mass drug administration (MDA) strategy. Additional use of insecticide treated mosquito nets (ITNs) might enhance elimination of LF infection. Between August 1998 and July 1999, all individuals aged ≥ 8 months from Magoda and Mpapayu villages in northeastern Tanzania, were administered with monthly low dose diethylcarbamazine (DEC) at a dosage of 50mg in children aged < 15 years and 100mg in adults aged ≥ 15 years. ITNs were also distributed to Magoda in December 1998 and to Mpapayu in March 2001. The main objective of our study was to assess the impact of ITNs and low dose DEC on microfilaria (mf) prevalence and intensity and incidence of new mf infections. Four annual cross-sectional surveys were conducted between 1999 and 2004 in the two villages to screen for Wuchereria bancrofti microfilariae in individuals aged ≥ 1 year. Overall, 80% of the population in Magoda and 66% in Mpapayu were covered during these surveys. Results revealed a significant decrease in both mf prevalence and intensity in both villages. Furthermore, there was a steady decrease in mf incidence in Magoda; with 36.7 cases per 1000 person years in 2000 and 7.4 in 2004. In Mpapayu, the incidence initially increased from 20.8 cases in 2000 to 24.3 in 2001 and then decreased to 7.2 cases in 2004. Individuals using ITNs in Magoda had significantly lower risk of mf (OR=0.681; 95%CI: 0.496-0.934); and the risk of new infections was reduced by 58.8% (95%CI: 30.3-75.4). These results suggest that when MDA is complemented with ITNs there is high likelihood to half filariasis transmission within a shorter period than using chemotherapy alone.

KW - Diethylcarbamazine

KW - Insecticide mosquito nets

KW - Lymphatic filariasis

KW - Tanzania

UR - http://www.scopus.com/inward/record.url?scp=84868151711&partnerID=8YFLogxK

U2 - 10.4314/thrb.v14i3.2

DO - 10.4314/thrb.v14i3.2

M3 - Journal article

C2 - 26591753

AN - SCOPUS:84868151711

SN - 1821-6404

VL - 14

JO - Tanzania Journal of Health Research

JF - Tanzania Journal of Health Research

IS - 3

ER -