Impact of mass distribution of free long-lasting insecticidal nets on childhood malaria morbidity: The Togo National Integrated Child Health Campaign

Abstract

Background: An evaluation of the short-term impact on childhood malaria morbidity of mass distribution of free

long-lasting insecticidal nets (LLINs) to households with children aged 9-59 months as part of the Togo National

Integrated Child Health Campaign.

Methods: The prevalence of anaemia and malaria in children aged zero to 59 months was measured during two

cross-sectional household cluster-sample surveys conducted during the peak malaria transmission, three months

before (Sept 2004, n = 2521) and nine months after the campaign (Sept 2005, n = 2813) in three districts

representative of Togo’s three epidemiological malaria transmission regions: southern tropical coastal plains (Yoto),

central fertile highlands (Ogou) and northern semi-arid savannah (Tone).

Results: In households with children <5 years of age, insecticide-treated net (ITN) ownership increased from <1%

to >65% in all 3 districts. Reported ITN use by children during the previous night was 35.9%, 43.8% and 80.6% in

Yoto, Ogou and Tone, respectively. Rainfall patterns were comparable in both years. The overall prevalence of

moderate to severe anaemia (Hb < 8.0 g/dL) was reduced by 28% (prevalence ratio [PR] 0.72, 95% CI 0.62-0.84) and

mean haemoglobin was increased by 0.35 g/dL (95% CI 0.25-0.45).

The effect was predominantly seen in children aged 18-59 months and in the two southern districts: PR (95% CI)

for moderate to severe anaemia and clinical malaria: Yoto 0.62 (0.44-0.88) and 0.49 (0.35-0.75); Ogou 0.54 (0.37-0.79)

and 0.85 (0.57-1.27), respectively. Similar reductions occurred in children <18 months in Ogou, but not in Yoto. No

effect was seen in the semi-arid northern district despite a high malaria burden and ITN coverage.

Conclusions: A marked reduction in childhood malaria associated morbidity was observed in the year following

mass distribution of free LLINs in two of the three districts in Togo. Sub-national level impact evaluations will

contribute to a better understanding of the impact of expanding national malaria control efforts.