The online version of this article (doi:10.1186/s12936-017-1767-2) contains supplementary material, which is available to authorized users.
The protective effect of insecticide-treated bed nets against individual-level malaria transmission is well known, however community-level effects are less understood. Protective effects from community-level bed net use against malaria transmission have been observed in clinical trials, however, the relationship is less clear outside of a controlled research setting. The objective of this research was to investigate the effect of community-level bed net use against malaria transmission outside of a bed net clinical trial setting in Lilongwe, Malawi following national efforts to scale-up ownership of long-lasting, insecticide-treated bed nets.
An annual, cross-sectional, household-randomized, malaria transmission intensity survey was conducted in Lilongwe, Malawi (2011–2013). Health, demographic, and geographic-location data were collected. Participant blood samples were tested for Plasmodium falciparum presence. The percentage of people sleeping under a bed net within 400-m and 1-km radii of all participants was measured. Mixed effects logistic regression models were used to measure the relationship between malaria prevalence and surrounding bed net coverage. Each year, 800 people were enrolled (400 <5 years; 200 5–19 years; 200 ≥20 years; total n = 2400).
From 2011 to 2013, malaria prevalence declined from 12.9 to 5.6%, while bed net use increased from 53.8 to 78.6%. For every 1% increase in community bed net coverage, malaria prevalence decreased among children under 5 years old [adjusted odds ratio: 0.98 (0.96, 1.00)]. Similar effects were observed in participants 5–19 years [unadjusted odds ratio: 0.98 (0.97, 1.00)]; the effect was attenuated after adjusting for individual-level bed net use. Community coverage was not associated with malaria prevalence among adults ≥20 years. Supplemental analyses identified more pronounced indirect protective effects from community-level bed net use against malaria transmission among children under 5 years who were sleeping under a bed net [adjusted odds ratio: 0.97 (0.94, 0.99)], compared to children who were not sleeping under a bed net [adjusted odds ratio: 0.99 (0.97, 1.01)].
Malawi’s efforts to scale up ownership of long-lasting, insecticide-treated bed nets are effective in increasing reported use. Increased community-level bed net coverage appears to provide additional protection against malaria transmission beyond individual use in a real-world context.
Additional file 1. Mixed effects logistic regression results for children under 5 years stratified by bed net use.
Additional file 2. Predicted margins with 95% confidence interval of Plasmodium falciparum infection in children <5 years old for per cent increase in bed net coverage within 400-m. a Children <5 years who sleep under a bed net; b children <5 years who do not sleep under a bed net.
Lengeler C. Insecticide-treated bed nets and curtains for preventing malaria. Cochrane Database Syst Rev. 2004;2:CD000363. doi: 10.1002/14651858.CD000363.pub2/pdf/.
Malawi Ministry of Health and National Malaria Control Programme. Malawi malaria indicator survey. Lilongwe: Malawi Ministry of Health; 2010.
Malawi Ministry of Health. Malaria strategic plan towards universal access 2011–2015. 2010. http://www.rollbackmalaria.org/files/files/countries/malawi2011-2015.pdf. Accessed 27 Feb 2016.
Measure DHS. Malawi demographic and health survey. 2010. https://dhsprogram.com/pubs/pdf/FR247/FR247.pdf. Accessed 19 May 2014.
Mathanga DP, Mwandama DA, Bauleni A, Chisaka J, Shah MP, Landman KZ, et al. The effectiveness of long-lasting, insecticide-treated nets in a setting of pyrethroid resistance: a case–control study among febrile children 6 to 59 months of age in Machinga District, Malawi. Malar J. 2015;14:457. CrossRefPubMedPubMedCentral
Binka FN, Indome F, Smith T. Impact of spatial distribution of permethrin-impregnated bed nets on child mortality in rural northern Ghana. Am J Trop Med Hyg. 1998;59:80–5. PubMed
Gimnig JE, Kolczak MS, Hightower AW, Vulule JM, Schoute E, Kamau L, et al. Effect of permethrin-treated bed nets on the spatial distribution of malaria vectors in western Kenya. Am J Trop Med Hyg. 2003;68(4 suppl):115–20. PubMed
Hawley WA, Phillips-Howard PA, ter Kuile FO, Terlouw DJ, Vulule JM, Ombok M, et al. Community-wide effects of permethrin-treated bed nets on child mortality and malaria morbidity in western Kenya. Am J Trop Med Hyg. 2003;68(4 suppl):121–7. PubMed
RTS,S Clinical Trial Partnership. Efficacy and safety of RTS, S/AS01 malaria vaccine with or without a booster dose in infants and children in Africa: final results of a phase 3, individually randomised, controlled trial. Lancet. 2015;386:31–45. CrossRef
Filmer D, Pritchett LH. Estimating wealth effects without expenditure data—or tears: an application to educational enrollments in states of India. Demography. 2001;38:115–32. PubMed
Silverman BW. Density estimation for statistics and data analysis. Boca Raton: CRC Press; 1986. CrossRef
Presidents malaria initiative: operational plan Malawi FY 2013. https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=presidents%20malaria%20initiative%20operational%20plan%20malawi%20FY%202013&*. Accessed 2 Feb 2016.
National Malaria Control Programme (NMCP) [Malawi] and ICF International. Malawi malaria indicator survey (MIS) 2014. 2014. https://dhsprogram.com/pubs/pdf/MIS18/MIS18.pdf. Accessed 1 Mar 2016.
- Effects of community-level bed net coverage on malaria morbidity in Lilongwe, Malawi
Jonathan J. Juliano
William C. Miller
Irving F. Hoffman
- BioMed Central
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