Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Randomized Controlled Trial
. 2016 Jul 22;15(1):378.
doi: 10.1186/s12936-016-1433-0.

A cluster randomized trial comparing deltamethrin and bendiocarb as insecticides for indoor residual spraying to control malaria on Bioko Island, Equatorial Guinea

John Bradley  1 , Dianna Hergott  2 , Guillermo Garcia  2 , Jo Lines  3 , Jackie Cook  4 , Michel A Slotman  5 , Wonder Philip Phiri  2 , Christopher Schwabe  2 , Immo Kleinschmidt  4   6
Affiliations
Randomized Controlled Trial

A cluster randomized trial comparing deltamethrin and bendiocarb as insecticides for indoor residual spraying to control malaria on Bioko Island, Equatorial Guinea

John Bradley et al. Malar J. .

Abstract

Background: Indoor residual spraying (IRS) has been used on Bioko for malaria control since 2004. In 2013 the insecticide was changed from bendiocarb to deltamethrin. Shortly after this change, there was a marked increase in malaria prevalence on the island. This trial was carried out to compare the effectiveness of bendiocarb and deltamethrin for use in IRS on Bioko.

Methods: Twenty-four clusters of houses were randomized to receive IRS with either bendiocarb or deltamethrin. Approximately 3 months after the intervention, the prevalence of malaria and levels of haemoglobin were measured in children aged 2-14 years in each cluster.

Results: Prevalence of malaria in 2-14 year olds was lower in the bendiocarb arm (16.8, 95 % CI 11.1-24.7, N = 1374) than in the deltamethrin arm (23.2, 95 % CI 16.0-32.3, N = 1330) but this difference was not significant (p = 0.390), even after adjusting for covariates (p = 0.119). Mean haemoglobin in children was marginally higher in the bendiocarb clusters (11.6 g/dl, 95 % CI 11.5-11.8, N = 1326) than in the deltamethrin clusters (11.5 g/dl, 95 % CI 11.3-11.7, N = 1329). This difference was borderline significant after adjusting for covariates (p = 0.049).

Conclusions: The results are suggestive of bendiocarb being more effective at preventing malaria on Bioko although evidence for this was weak. The results are likely due to the fact that local vectors remain fully susceptible to bendiocarb whereas subsequent tests have shown resistance to deltamethrin.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
Overview of trial
Fig. 2
Fig. 2
The trial clusters in Central Malabo. The shaded area around the cluster represents the buffer zone. Pink clusters were sprayed with deltamethrin and blue clusters with bendiocarb
See this image and copyright information in PMC

References

    1. Pluess B, Tanser FC, Lengeler C, Sharp BL. Indoor residual spraying for preventing malaria. Cochrane Database Syst Rev. 2010;4:4. - PMC - PubMed
    1. Najera JA, Gonzalez-Silva M, Alonso PL. Some lessons for the future from the global malaria eradication programme (1955–1969) PLoS Med. 2011;8:e1000412. doi: 10.1371/journal.pmed.1000412. - DOI - PMC - PubMed
    1. WHO. World Malaria Report 2015. Geneva: World Health Organization. 2015. http://www.who.int/malaria/publications/world-malaria-report-2015/en/. Accessed June 2016.
    1. Sharp BL, Ridl FC, Govender D, Kuklinski J, Kleinschmidt I. Malaria vector control by indoor residual insecticide spraying on the tropical island of Bioko, Equatorial Guinea. Malar J. 2007;6:52. doi: 10.1186/1475-2875-6-52. - DOI - PMC - PubMed
    1. Kleinschmidt I, Schwabe C, Benavente L, Torrez M, Ridl FC, Segura JL, et al. Marked increase in child survival after four years of intensive malaria control. Am J Trop Med Hyg. 2009;80:882–888. - PMC - PubMed

Publication types