The success and popularity of Long Lasting Insecticidal net (LLIN) campaigns combined with the agricultural use of insecticides has contributed to the emergence of pyrethroid insecticide resistance among mosquito populations in Africa and other malaria endemic countries. Olyset Plus is the ‘bite-back’ solution with enhanced knockdown and kill against pyrethroid-resistant mosquitoes.
Olyset Plus is a durable polyethylene net containing 2% permethrin combined with 1% of the synergist PBO (piperonyl butoxide), which is incorporated into all the fibres on each side including the roof. Using patented slow-release technology, the net fibres release the two ingredients at a constant ratio of 2:1, ensuring optimum efficacy against mosquitoes, including those that are resistant, in even the toughest conditions.
For more information on insecticide resistance please visit Insecticide Resistance Action Committee’s (IRAC) guidance on ‘Prevention and Management of Insecticide Resistance In Vectors of Public Health Importance’
How does Olyset Plus work?
Olyset Plus Regeneration
Building on Olyset Net technology, liquid permethrin is released into tough polyethylene fibres, but with the addition of PBO to boost efficacy. The rate in which PBO and permethrin migrate from the fibre’s internal reservoir to the surface of the net has been adjusted in Olyset Plus to provide rapid regeneration, making the net fully active again within 1-2 days after washing.
We believe that in areas where resistant mosquitoes have been found, rapid regeneration after washing of both synergist and insecticide is required to ensure that LLINs repel, kill and prevent mosquitos from biting adults and young children.
What is Piperonyl Butoxide?
Piperonyl butoxide (PBO) is a synergist which has been safely used for over 50 years to enhance the performance of pyrethroid insecticides, especially in household aerosols. When combined with permethrin, the protective effect of the insecticide is dramatically increased.
How does Piperonyl Butoxide combat resistance?
All insects, whether susceptible or resistant, have enzymes that can metabolise insecticides into harmless components. Some of these enzymes, known as cytochrome P450s, are powerful oxidising agents that can detoxify an active ingredient before the desired effect is achieved. By adding PBO, this action can be blocked. The synergist inhibits the breakdown or the metabolism of insecticides in resistant insects, rendering the insecticide more effective; while at the same time the activity of pyrethroids to susceptible insects is increased. For this reason, adding PBO to an LLIN is beneficial even in areas where there is no insecticide resistance.
Distribution of pyrethroid resistance in Africa using data collected between 2000 to 2010
Due to the excellent results from LLIN campaigns the adoption of pyrethroid treated nets as a key intervention in the battle against malaria has reached new heights. In many endemic countries, usage had reached 80% by 2011. Yet the pressure of using a single class of insecticides, pyrethroids, in all LNs as well as for Indoor Residual Spraying and agriculture has resulted in insecticide resistance in many parts of the world, particularly in Africa.
Reference: Ranson et al, Trends in Parasitology, Feb 2011, Vol 27, No.2
Olyset Plus is the first and only net on the market to incorporate PBO into every fibre and all surfaces of the net, providing enhanced knockdown and kill against pyrethroid-resistant mosquitoes.