Crop protection companies collaborate on global malaria prevention strategies
Cases of malaria are now back on the increase, but new initiatives led by national administrations, the private sector and non-governmental organisations such as the Bill and Melinda Gates Foundation are leading the fightback.
At the Malaria Summit in London last week (April 18), attended by Commonwealth leaders, funding commitments of more than £2.9 billion ($4.1bn) were made.
“History has shown that with malaria there is no standing still – we move forward or risk resurgence,” Bill Gates, whose organisation has committed US$1 billion in new finance over the next five years, said at the event.
“It’s a disease that is preventable, treatable and ultimately beatable, but progress against malaria is not inevitable. We hope this marks a turning point against the disease, and that the Commonwealth takes a leading role in saving lives and ending malaria for good.”
Commonwealth leaders are being urged to commit to halving cases of the disease by 2023, with around 90% of those living in their countries exposed to malaria-carrying mosquitoes.
This initiative would help to prevent 350 million cases of malaria over the next five years, and save 650,000 lives, predominantly of children and pregnant women, who remain the groups most at risk.
As a new report, produced by IEG Policy’s sister title Animal Pharm, has demonstrated, the worldwide commitment to eradicate malaria has also highlighted the need to develop a cadre of professionals who understand the ecology of the vectors involved in its transmission, such as its pioneering author, Dr Jacques Derek Charlwood, who has worked in Eritrea, Mozambique, Tanzania; and São Tomé and Princípe, among others.
From the agribusiness and crop protection sectors, several new innovative products have been announced to overcome the growing threat of insecticide resistance.
Five major crop protection companies - BASF, Bayer, Mitsui Chemicals, Sumitomo Chemical, and Syngenta, have launched ZERO by 40, a joint initiative supported by the Liverpool, UK-based Innovative Vector Control Consortium (IVCC), and the Bill and Melinda Gates Foundation, to accelerate development of innovative vector control tools, and completely eliminate malaria globally by 2040.
In 2008, these companies provided the IVCC with access to their chemical libraries, to support the search for novel insecticide modes of action that could be developed for public health use.
A decade on, this collaboration between the public and private sectors has produced a pipeline of novel vector control solutions for malaria and other vector-borne diseases, said IVCC CEO Dr Nick Hamon. “Some 4.5 million compounds have been examined over the past decade and our job now is to get this down to the 3 or 4 most effective compounds,” he explained.
Some 663 million cases of malaria have been averted since 2000, 78% of which are directly due to mosquito control interventions, such as sprays and bed nets.
However, the malaria parasite and the mosquitoes that carry it are continually evolving resistance to existing interventions. In 2016, the number of global malaria cases reached 216 million, up 5 million on the previous year, demonstrating the need for novel approaches.
Nets have traditionally been impregnated with pyrethroid-based compounds, but resistance is increasingly widespread.
So the introduction of nets treated with piperonyl butoxide (PBO), a synergist which increases the performance of the active ingredient permethrin and enhances activity against both susceptible and pyrethroid-resistant mosquitoes, is being warmly awaited.
The Against Malaria Foundation has purchased some 6 million of these PBO enhanced long-lasting Olyset Plus nets, manufactured by Vestergaard and Sumitomo, for a large trial across Uganda, expected in 2019.
Meanwhile, Sumitomo has also launched SumiShield 50WG, an Indoor Residual Spray (IRS), based on clothiandin, a neonicotinoid insecticide, which is being used in Ghana, after a pilot campaign in Tanzania.
BASF has received a recommendation from the World Health Organization (WHO) for Interceptor G2, a long-lasting insecticide-treated mosquito net based on chlorfenapyr, creating a completely new insecticide class for combating mosquitoes for public health. This is the first WHO recommendation for a product based on a new insecticide class in more than 30 years.
A second chlorfenapyr-based product, an IRS branded as Sylando 240SC, is also in the final phases of WHO evaluation. However, a BASF spokesperson emphasised that despite WHO approval, which is favoured by donors, these products still need to meet regulatory requirements in each country, adding to the timeframe and costs for eventual adoption.
Bayer’s Fludora Fusion, combining the active ingredients clothianidin and deltamethrin, a neonicotinoid and a pyrethroid, is currently undergoing the final stages of trials required for WHO pre-qualification. Syngenta also has its Icon and Actellic advanced mosquito control products.
Outdoor biting adult mosquitos are also being tackled by an Attractive Toxic Sugar Bait (ATSB) technology being trialled in Mali, and developed by Israeli company Westham. This novel solution decimates mosquito populations in their natural environment using a patented ‘attract & kill’ method based on the instinct of mosquitoes to feed on sugar for energy.
“Mosquitoes have adapted to indoor insecticides by altering their behaviour and becoming more active outside, in the open air,” said Dr Nick Hamon, CEO of the IVCC.
Improved methods to track malaria in the field are also being launched, such as DiSARM, which uses Google Earth as a mapping tool, with data processed via tablets and smartphones.
Health workers in Botswana and Namibia are using it to predict where malaria outbreaks will next occur. Pilots are planned also for South Africa and Zimbabwe for smart interventions, so that sprays, bed nets and medicines can be delivered in a timely strategy where they are most urgently needed.
The use of mobile phones, big data and artificial intelligence tools, such as by San Francisco-based Zenysis Technologies in Ethiopia, should also help to tackle the significant impact of malaria on farmers. Syngenta has estimated that crop yields fall 48% on average when a smallholder is infected during the harvest season.
Drones such as the DJI Phantom are likewise being deployed to better target insecticide spraying in Zanzibar, pioneered by Aberystwyth University in Wales, to survey malaria hot spots and identify water-laden areas where malaria-carrying mosquitoes are prevalent for breeding.
For further details of Animal Pharm’s report Ecology of Malaria Vectors, please follow this link.