Integrated Vector Management for the Control of Vector Borne Diseases
Submitting InstitutionUniversity of Durham
Unit of AssessmentBiological Sciences
Summary Impact TypeHealth
Research Subject Area(s)
Medical and Health Sciences: Medical Microbiology
Summary of the impact
Integrated Vector Management (IVM) was developed by the World Health
Organisation to control vector borne diseases using combinations of
interventions. Professor Steve Lindsay and his team have contributed to
the development and assessment of many of the tools used for vector
control, including insecticide-treated bed nets (ITNs), larval source
management and house screening for malaria control. This research has
influenced international policy on the control of malaria and other
important diseases. It is estimated that 294 million ITNs have been
purchased for malaria control, and have helped save 1.1 million lives over
the past decade.
IVM has lacked evidence about many of the potential tools that could be
used for vector control and there has been little evidence supporting the
use of combinations of tools for the control of VBDs. Prof Lindsay and
colleagues have carried out studies in Africa to measure the efficacy of a
range of vector control tools against malaria and other major VBDs, and
his teams carried out 3 of the 4 major recent trials of microbial
larvicides in Africa. These studies have provided important evidence
required for making policy decisions for disease control. Importantly,
unusually and in-line with the IVM strategy, some of these tools, such as
screened housing, can be used by development agencies outside the health
Prof. Lindsay was a member of the team which first demonstrated that
insecticide treated bednets (ITNs) reduced deaths from malaria in African
children2. Since treated nets and indoor residual spraying of
insecticides target only indoor mosquitoes, further reductions in
transmission were proposed to be achieved by targeting outdoor biting
mosquitoes. This led to the group carrying out large-scale field trials of
microbial larvicides to control both indoor and outdoor biting vector
mosquitoes in Kenya, Tanzania and The Gambia3. This work
demonstrated that (1) larval control could reduce malaria transmission in
Africa, which challenged the accepted dogma, and (2) larviciding by ground
teams failed to work in areas with extensive breeding sites. Of particular
note was the field trial conducted in the Western Kenyan Highlands where
long-lasting insecticidal nets were combined with larval control which
demonstrated for the first time that combinations of interventions can
provide additional protection against malaria infection in children3.
The importance of larval source management for malaria control was also
highlighted by Lindsay's recent meta-analysis for the Cochrane Library4.
These studies are internationally recognised as being the strongest
evidence for assessing the efficacy of any health intervention.
In recent years we have seen a rise in mosquitoes resistant to
insecticides used on nets or walls, and in the future we may lack
effective insecticides for malaria control threatening the hard-won gains
made over the past 10 years. The Durham team therefore carried out a
randomised controlled trial in The Gambia to determine whether house
screening, with no insecticides, would protect children against malaria.
It found that house screening reduced anaemia in children by half5.
Since anaemia is a major killer of children under two years old, house
screening is also likely to protect young children from dying from
malaria. This work has strengthened the hypothesis that socio-economic
development should be considered as a `health intervention'. A systematic
review and meta-analysis published in The Lancet1 demonstrated
that the poorest were twice as likely to have malaria than the less poor,
implying that development may well act as an effective long-term
intervention against malaria.
The Durham group also studies fly-borne diseases, and was the first to
demonstrate that the human face fly, Musca sorbens, transmitted
trachoma an important cause of blindness in the world. Importantly they
showed that fly control by space spraying insecticides or installing pit
latrines could reduce trachoma in African children (Emerson, Lindsay)6.
References to the research
1. Tusting L, Willey B, Lucas H, Thompson J, Kafy HT, Smith R, Lindsay SW
(2013) Is socio-economic development the most cost-effective
`intervention' against malaria? The Lancet 382: 963-72.
2. Alonso PL, Lindsay SW, Armstrong Schellenberg JRM, Gomez, P, Hill, AG,
David, PH, Fegan, G, Cham, K & Greenwood, B.M. (1993) A malaria
control trial using insecticide-treated bed nets and targeted
chemoprophylaxis in a rural area of The Gambia, West Africa. 2. Mortality
and morbidity from malaria in the study area. Transactions of the
Royal Society of Tropical Medicine and Hygiene 87, supplement 2:
13-8. DOI: 10.1016/0035-9203(93)90170-U.
3. Fillinger U, Ndenga B, Githeko A, Lindsay SW (2009). Integrated
malaria vector control with microbial larvicides and insecticide-treated
nets in western Kenya: A controlled trial. Bulletion of the World
Health Organization; 87: 655-65. DOI: 10.2471/BLT.08.055632
4. Tusting L, Thwing J, Sinclair D, Fillinger U, Gimnig J, Bonner KE,
Bottomley C, Lindsay SW (2013) Mosquito larval source management for
controlling malaria (Review). The Cochrane Library 8: DOI:
5. Kirby MJ, Ameh D, Bottomley C, Green C, Jawara M, Milligan PJ, Snell
PC, Conway DJ, Lindsay S. W. (2009) Effect of two different house
screening interventions on exposure to malaria vectors and on anaemia in
children in The Gambia: a randomised controlled trial. The Lancet;
374: 998-1009. DOI: 10.1016/S0140-6736(09)60871-0.
6. Emerson PM, Lindsay SW, Alexander N, Bah M, Dibba SM, Faal HB, Lowe K,
McAdam KPWJ, Ratcliffe AA, Walraven GEL, Bailey RL (2004). Role of flies
and provision of latrines in trachoma control: cluster-randomised
controlled trial. The Lancet 363: 1093-8. http://dx.doi.org/10.1016/S0140-
Grants supporting the research described above.
UNDP/World Bank/WHO Special Programme for Research and Training in
(TDR). A malaria control trial using insecticide-treated bed nets and
targeted chemoprphylaxis in a rural area of The Gambia, West Africa.
Edna McConnell Clarke Foundation. A community randomised intervention
against house flies for the control of trachoma and diarrhoea. £95,808.
August 1999-July 2002.
Department for International Development. Health and Population Division
(R7448, RD567). Trachoma and diarrhoea transmission by synanthropic flies
with the development of sustainable strategies for fly control. £324,867.
August 1999- July 2002.
Environmental Health Project, United States Agency for International
Development. Field Studies of Anti-larval Methods for Malaria Control in
Africa. $359,027. January 2003-August 2004 (R020411).
National Institutes of Health, USA. Anti-larval measures for malaria
control in The Gambia. $2,090,895. September 2003-August 2008.
Medical Research Council. House screening against malaria. £534,000. 1st
May 2005-31st October 2008 (R020583).
Bill & Melinda Gates Foundation Framework for Integrated Vector
Control. $1M. 1st September 2012- 28th February
Details of the impact
The research trial described in Section 2 led to the World Health
Organisation (WHO) carrying out further studies across sub-Saharan Africa
which confirmed the results, demonstrating that using insecticide-treated
nets (ITNs) resulted in a 20% fall in mortality in children under five
years old . Today treated nets are the major tool used for reducing
malaria in Africa and many parts of the tropics . They are cheap and
cost only US$1.39 per person per year of protection (www.rbm.who.int/keyfacts.html,
accessed 25th April 2013). It is estimated that 294 million
nets were purchased for malaria control between 2008 and 2010, enough to
cover 73% of the 800 million people living at risk of malaria . As a
consequence the percentage of households with at least one ITN in
sub-Saharan Africa has risen from 3% in 2000 to 53% in 2012 . It is
estimated that the massive roll-out of ITNs and, to a lesser extent,
indoor residual spraying, has saved 1.1 million lives .
Over the last 10 years Lindsay's teams carried out 3 of the 4 major
recent trials of microbial larvicides in Africa: in Kenya,
Tanzania and The Gambia . The results from this trial
provided WHO with much needed information on the protective efficacy of
this intervention and led to larval source management being recognised by
WHO in an `Interim Position Statement on the role of larviciding for
malaria control in sub-Saharan Africa' that references this work . For
the first time Larval Source Management was included in the World Malaria
Report in 2012, which is a statement of support for this intervention.
In recent years the interest in larval control for malaria control has
grown and there are presently 27 malaria endemic countries using larval
control for malaria control, including 9 in Africa, 5 in the Americas, 3
in the Eastern Mediterranean, 6 in Europe, 2 in South-East Asia and 2 in
the Western Pacific . Since these countries look to WHO for advice on
malaria control, the work done by Lindsay and colleagues has significantly
influenced the uptake of this intervention, providing the evidence that
larval control is an effective intervention against malaria.
Lindsay is presently the Chair of the Larval Source Management workstream
for the Roll Back Malaria Partnership, a global framework for coordinated
action against malaria that informs international policy. This workstream
provides the technical support for WHO and national malaria control
managers around the world by providing the evidence required for decision
making. Lindsay and his team, supported by WHO, have (1) carried out the
analysis and written the Cochrane review on Larval Source Management
, which provides the evidence that this intervention is
protective and (2) led and written the WHO manual on larval source
management that shows national control managers how to implement this
intervention. Thus the work of this team has contributed
to larval source management being supported by WHO and have provided
material that assists national malaria control programme managers around
The team also demonstrated for the first time that Musca sorbens,
the face fly of humans, transmits trachoma, the second cause of
preventative blindness in the world. This is recognised by WHO (http://www.who.int/topics/trachoma/en/)
and the International Coalition for Trachoma Control
Carter Center had planned to construct 10,000 latrines in rural Ethiopia
to improve sanitation by reducing face fly breeding in surface faeces. The
program was so successful more than 90,000 latrines were ultimately
constructed. This activity was directly related to our demonstration that
face flies transmit trachoma (http://www.cartercenter.org/news/documents/doc2198.html).
Latrines reduce fly numbers because these flies do not enter latrines to
Because of Prof Lindsay's expertise in the development of new tools for
vector control he has been invited to participate and chair several
meetings helping to shape WHO's policy on IVM and contributed to the
'Report of the WHO consultation on integrated vector management (IVM)'
 and `Development of a global action plan for integrated vector
management (IVM) Report of a WHO Consultation'  which led to WHO
adopting this policy  and producing a handbook on IVM  which
references some of his team's research. He also provides support to the
Bill and Melinda Gates Foundation, advising on funding vector control
research and has recently joined WHO's Vector Control Advisory Group
(VCAG) on New Tools. His work on health and development also influences
policy at the highest international level and his work  is referenced
repeatedly in the recent policy document produced by Roll Back
Malaria/UNDP entitled `Multisectoral Action Framework for Malaria' 
which represents a new approach to global malaria control.
Sources to corroborate the impact
- Lengeler C. Insecticide-treated bed nets and curtains for preventing
malaria. The Cochrane Database of Systematic Reviews. 2004; (2):
CD000363 pub2. DOI: 10.1002/146.
- WHO. World Malaria Report 2011. Geneva: World Health Organization;
- WHO. World malaria report. 2012. Geneva: World Health Organization;
- Geissbühler Y, Kannady K, Chaki PP, Emidi B, Govella NJ, Mayagaya V,
et al. Microbial larvicide application by a large-scale, community-based
program reduces malaria infection prevalence in urban Dar Es Salaam,
Tanzania. PLoS ONE. 2009; 4(3).
- Majambere S, Pinder M, Fillinger U, Ameh D, Conway DJ, Green C, et al.
Is mosquito larval source management appropriate for reducing malaria in
areas of extensive flooding in The Gambia? a cross-over intervention
trial. Am J Trop Med Hyg. 2010; 82: 176-84.
- WHO. Interim Position Statement: The role of larviciding for malaria
control in sub-Saharan Africa. Geneva: World Health Organization; 2012.
- WHO. Larval Source Management. A supplement ary measure for malaria
vector control. Geneva: WHO; 2013. http://apps.who.int/iris/bitstream/10665/85379/1/9789241505604_eng.pdf
- WHO. Report of the WHO consultation on integrated vector management
(IVM). Geneva: World Health Organization; 2007. http://whqlibdoc.who.int/hq/2007/WHO_CDS_NTD_VEM_2007.1_eng.pdf
- WHO. Development of a global action plan for integrated vector
management (IVM) Report of a WHO Consultation. Geneva: World Health
Organization; 2008. http://whqlibdoc.who.int/hq/2009/WHO_HTM_NTD_VEM_2009.1_eng.pdf
- WHO. WHO position statement on integrated vector management. Wkly
Epidemiol Rec. 2008; 83(20): 177-81. http://www.unboundmedicine.com/harrietlane/ub/citation/18488269/WHO_position_statement_
- WHO. Handbook on Integrated Vector Management (IVM). Geneva: World
Health Organization; 2010. p. 78 http://whqlibdoc.who.int/publications/2012/9789241502801_eng.pdf
- RBM/UNDP. Multisectoral action framework for malaria Geneva,
Switzerland: UNDP and RBM; 2013. http://reliefweb.int/sites/reliefweb.int/files/resources/Multisectoral-Action-Framework-for-