6 June 2012 | EN | FR
Bednets may become less effective with rising insecticide resistance in mosquitoes
[KAMPALA] The WHO has launched a strategic plan to curb the spread of insecticide-resistant mosquitoes, which have already been identified in 64 malaria-ridden countries, most of them in Sub-Saharan Africa.
The Global Plan for Insecticide Resistance Management, published last month (15 May), includes a research agenda geared towards developing innovative new vector control tools and frameworks for tackling mosquitoes without using traditional insecticides.
The new tools include repellents, sugar- or odour-baited traps, and the treatment of other animal vectors, which mosquitoes feed on, to inhibit mosquito survival.
The WHO also recommends setting up a vector control advisory group, responsible for evaluating evidence related to new forms of vector control — currently a neglected area.
"This group would consist of experts in a range of entomological and vector control disciplines," the plan says. An important focus area would be the clarification and acceleration of the processes by which new tools are integrated into public health practice.
The plan calls for capacity building in entomology, and more partnerships with regional and local research institutes, as well as a global insecticide resistance database. It presents a pipeline of new products at different stages of development — from proof of concept to country registration level.
The plan's research agenda is one of five 'pillars' of the WHO's short-term action plan, aimed at different stakeholders, including the agricultural sector, governments, funding agencies and academic institutions. Other pillars include insecticide resistance management and monitoring.
James Ssekitooleko, of the integrated community case management project being implemented by the Malaria Consortium, with support from the Canadian International Development Agency, in Uganda, said high levels of resistance will render bednets and indoor residue spraying ineffective.
According to the WHO, insecticide resistance could result in 26 million more malaria cases every year, and necessitate spending an extra US$30–60 million annually on tests and medicines.
More research was required into the causes of resistance and the management of its spread, Ssekitooleko said, adding that the outstanding challenges were both the uncontrolled use of chemicals and inadequate surveillance for monitoring the spread of resistance.
Myers Lugemwa, team leader at the Ugandan Ministry of Health's malaria control programme, agreed that resistance must be monitored through susceptibility studies, and curbed by alternating use of different insecticides.
Lugemwa said the ministry was currently studying mosquitoes' susceptibility to different chemicals, but that research of this type required further government funds, which were not yet available.
John Vulule, head of the Centre for Global Health Research at the Kenya Medical Research Institute, told SciDev.Net: "Ensuring that local vector populations remain susceptible to prescribed insecticides is a prerequisite for the success of vector control, and a key step towards eradicating malaria."
Link to the action plan [2.1MB]
Additional reporting by Ochieng' Ogodo.
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