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
. 2010 Apr 14;2010(4):CD006657.
doi: 10.1002/14651858.CD006657.pub2.

Indoor residual spraying for preventing malaria

Bianca Pluess  1 , Frank C Tanser, Christian Lengeler, Brian L Sharp
Affiliations

Indoor residual spraying for preventing malaria

Bianca Pluess et al. Cochrane Database Syst Rev. .

Abstract

Background: Primary malaria prevention on a large scale depends on two vector control interventions: indoor residual spraying (IRS) and insecticide-treated mosquito nets (ITNs). Historically, IRS has reduced malaria transmission in many settings in the world, but the health effects of IRS have never been properly quantified. This is important, and will help compare IRS with other vector control interventions.

Objectives: To quantify the impact of IRS alone, and to compare the relative impacts of IRS and ITNs, on key malariological parameters.

Search strategy: We searched the Cochrane Infectious Diseases Group Specialized Register (September 2009), CENTRAL (The Cochrane Library 2009, Issue 3), MEDLINE (1966 to September 2009), EMBASE (1974 to September 2009), LILACS (1982 to September 2009), mRCT (September 2009), reference lists, and conference abstracts. We also contacted researchers in the field, organizations, and manufacturers of insecticides (June 2007).

Selection criteria: Cluster randomized controlled trials (RCTs), controlled before-and-after studies (CBA) and interrupted time series (ITS) of IRS compared to no IRS or ITNs. Studies examining the impact of IRS on special groups not representative of the general population, or using insecticides and dosages not recommended by the World Health Organization (WHO) were excluded.

Data collection and analysis: Two authors independently reviewed trials for inclusion. Two authors extracted data, assessed risk of bias and analysed the data. Where possible, we adjusted confidence intervals (CIs) for clustering. Studies were grouped into those comparing IRS with no IRS, and IRS compared with ITNs, and then stratified by malaria endemicity.

Main results: IRS versus no IRSStable malaria (entomological inoculation rate (EIR) > 1): In one RCT in Tanzania IRS reduced re-infection with malaria parasites detected by active surveillance in children following treatment; protective efficacy (PE) 54%. In the same setting, malaria case incidence assessed by passive surveillance was marginally reduced in children aged one to five years; PE 14%, but not in children older than five years (PE -2%). In the IRS group, malaria prevalence was slightly lower but this was not significant (PE 6%), but mean haemoglobin was higher (mean difference 0.85 g/dL).In one CBA trial in Nigeria, IRS showed protection against malaria prevalence during the wet season (PE 26%; 95% CI 20 to 32%) but not in the dry season (PE 6%; 95% CI -4 to 15%). In one ITS in Mozambique, the prevalence was reduced substantially over a period of 7 years (from 60 to 65% prevalence to 4 to 8% prevalence; the weighted PE before-after was 74% (95% CI 72 to 76%).Unstable malaria (EIR < 1): In two RCTs, IRS reduced the incidence rate of all malaria infections;PE 31% in India, and 88% (95% CI 69 to 96%) in Pakistan. By malaria species, IRS also reduced the incidence of P. falciparum (PE 93%, 95% CI 61 to 98% in Pakistan) and P. vivax (PE 79%, 95% CI 45 to 90% in Pakistan); There were similar impacts on malaria prevalence for any infection: PE 76% in Pakistan; PE 28% in India. When looking separately by parasite species, for P. falciparum there was a PE of 92% in Pakistan and 34% in India; for P. vivax there was a PE of 68% in Pakistan and no impact demonstrated in India (PE of -2%).IRS versus Insecticide Treated Nets (ITNs)Stable malaria (EIR > 1): Only one RCT was done in an area of stable transmission (in Tanzania). When comparing parasitological re-infection by active surveillance after treatment in short-term cohorts, ITNs appeared better, but it was likely not to be significant as the unadjusted CIs approached 1 (risk ratio IRS:ITN = 1.22). When the incidence of malaria episodes was measured by passive case detection, no difference was found in children aged one to five years (risk ratio = 0.88, direction in favour of IRS). No difference was found for malaria prevalence or haemoglobin.Unstable malaria (EIR < 1): Two studies; for incidence and prevalence, the malaria rates were higher in the IRS group compared to the ITN group in one study. Malaria incidence was higher in the IRS arm in India (risk ratio IRS:ITN = 1.48) and in South Africa (risk ratio 1.34 but the cluster unadjusted CIs included 1). For malaria prevalence, ITNs appeared to give better protection against any infection compared to IRS in India (risk ratio IRS:ITN = 1.70) and also for both P. falciparum (risk ratio IRS:ITN = 1.78) and P. vivax (risk ratio IRS:ITN = 1.37).

Authors' conclusions: Historical and programme documentation has clearly established the impact of IRS. However, the number of high-quality trials are too few to quantify the size of effect in different transmission settings. The evidence from randomized comparisons of IRS versus no IRS confirms that IRS reduces malaria incidence in unstable malaria settings, but randomized trial data from stable malaria settings is very limited. Some limited data suggest that ITN give better protection than IRS in unstable areas, but more trials are needed to compare the effects of ITNs with IRS, as well as to quantify their combined effects.

PubMed Disclaimer

Conflict of interest statement

None known.

Figures

Figure 1
Figure 1
Methodological quality graph: review authors' judgements about each methodological quality item presented as percentages across all included studies.
Figure 2
Figure 2
Methodological quality summary: review authors' judgements about each methodological quality item for each included study.
See this image and copyright information in PMC

Update of

  • doi: 10.1002/14651858.CD006657

References

References to studies included in this review

    1. Curtis CF. Royal Society of Tropical Medicine and Hygiene Meeting at Manson House, London, 21 January 1999 ‐ Malaria control: bednets or spraying? Background trial in Tanzania. Transactions of the Royal Society of Tropical Medicine and Hygiene 1999;93(5):453‐4. - PubMed
    2. Curtis CF, Maxwell CA, Finch RJ, Njunwa KJ. A comparison of use of a pyrethroid either for house spraying or for bednet treatment against malaria vectors. Tropical Medicine & International Health1998; Vol. 3, issue 8:619‐31. - PubMed
    1. Bhatia MR, Fox‐Rushby J, Mills A. Cost‐effectiveness of malaria control interventions when malaria mortality is low: insecticide‐treated nets versus in‐house residual spraying in India. Social Science & Medicine 2004;59(3):525‐39. - PubMed
    2. Misra SP. Indoor residual spray versus treated mosquito nets using deltamethrin to control malaria ‐ a community randomized trial in rural Surat, India (PhD thesis). London: University of London, 1999.
    3. Misra SP, Webber R, Lines J, Jaffar S, Bradley DJ. Malaria control: bednets or spraying? Spray versus treated nets using deltamethrin‐‐a community randomized trial in India. Transactions of the Royal Society of Tropical Medicine and Hygiene 1999;93(5):456‐7. - PubMed
    1. Goodman CA, Mnzava AE, Dlamini SS, Sharp BL, Mthembu DJ, Gumede JK. Comparison of the cost and cost‐effectiveness of insecticide‐treated bednets and residual house‐spraying in KwaZulu‐Natal, South Africa. Tropical Medicine & International Health 2001;6(4):280‐95. - PubMed
    2. Mnazva AE, Dlamini SS, Sharp BL, Mthembu DJ, Gumede K, Kleinschmidt I, et al. Malaria control: bednets or spraying? Trial in Kwazulu‐Natal, South Africa. Transactions of the Royal Society of Tropical Medicine and Hygiene 1999;93(5):455‐6. - PubMed
    3. Mnzava AE, Sharp BL, Mthembu DJ, Sueur D, Dlamini SS, Gumede JK, et al. Malaria control‐‐two years' use of insecticide‐treated bednets compared with insecticide house spraying in KwaZulu‐Natal. South African Medical Journal2001; Vol. 91, issue 11:978‐83. - PubMed
    1. Molineaux L, Gramiccia G. The Garki Project. Research on the Epidemiology and Control of Malaria in the Sudan Savanna of West Africa. Geneva: World Health Organization, 1980.
    1. Rowland M, Mahmood P, Iqbal J, Carneiro I, Chavasse D. Indoor residual spraying with alphacypermethrin controls malaria in Pakistan: a community‐randomized trial. Tropical Medicine & International Health 2000;5(7):472‐481. - PubMed

References to studies excluded from this review

    1. Afifi SED. Malaria eradication pilot projects with special reference to Saudi Arabia (EM/ME‐Tech.2/11). Second Regional Conference on Malaria Eradication;1959 Nov 16‐21; Addis Ababa. Geneva: World Health Organization, 1959.
    1. Afridi MK, Bhatia ML. Malaria control of villages around Quetta (Baluchistan) with D.D.T. Indian Journal of Malariology 1947;1(2):279‐87. - PubMed
    1. Alves W, Blair DM. An experiment in the control of malaria and bilharziasis. Transactions of the Royal Society of Tropical Medicine and Hygiene 1953;47(4):299‐308. - PubMed
    1. Andrews JM. Nation‐wide malaria eradication projects in the Americas. I. The eradication program in the U.S.A. Journal. National Malaria Society 1951;10(2):99‐123. - PubMed
    1. Ansari MA, Sharma VP, Batra CP, Razdan RK, Mittal PK. Village scale trial of the impact of deltamethrin (K‐othrine) spraying in areas with DDT and HCH resistant Anopheles culicifacies. Indian Journal of Malariology1986; Vol. 23, issue 2:127‐31. - PubMed

References to studies awaiting assessment

    1. Kere JF, Kere NK. Bed‐nets or spraying? Cost analyses of malaria control in the Solomon Islands. Health Policy and Planning 1992;7(4):382‐6.
    2. Kere NK. Permethrin impregnated bednets and DDT residual spraying multicentre comparative trial in Solomon Islands [PhD thesis]. London: University College London, 1992.

Additional references

    1. Adinarayanan S, Critchley J, Das PK, Gelband H. Diethylcarbamazine (DEC)‐medicated salt for community‐based control of lymphatic filariasis. Cochrane Database of Systematic Reviews 2007, Issue 1. [DOI: 10.1002/14651858.CD003758.pub2] - DOI - PMC - PubMed
    1. Bennett S, Parpia T, Hayes R, Cousens S. Methods for the analysis of incidence rates in cluster randomized trial. International Journal of Epidemiology 2002;31:839‐846. - PubMed
    1. Carneiro IA, Drakeley CJ, Owusu‐Agyei S, Mbando B, Chandramohan D. Haemoglobin and haematocrit: is the threefold conversion valid for assessing anaemia in malaria‐endemic settings?. Malaria Journal 2007;6(67). [DOI: 10.1186/1475-2875-6-67] - DOI - PMC - PubMed
    1. Curtis C, Mnzava A. Treated nets vs house spraying. Bulletin of the World Health Organization 2001;79(7):687. - PMC - PubMed
    1. Cochrane Effective Practice and Organisation of Care Review Group (EPOC). The data collection checklist. www.epoc.uottawa.ca/checklist2002.doc 2002 (accessed 12 May 2007).

Publication types