This site uses cookies to collect activity data and personalize content. By continuing to navigate this site, you agree to allow us to collect information using cookies. Learn more about how we care for your data in our privacy notice.

Accept

Promising new tools against malaria

December 27, 2021 by Molly Robertson

Mosquito nets treated with new ingredients show greater reductions in malaria than standard insecticide-treated nets.

Changara District, Mozambique, in October 2021 during durability monitoring data collection. Durability monitoring measures the physical condition and effectiveness of the chemicals on bed nets over time. Photo: PATH/Molly Robertson.

Changara District, Mozambique, in October 2021 during durability monitoring data collection. Durability monitoring measures the physical condition and effectiveness of the chemicals on bed nets over time. Photo: PATH/Molly Robertson.

Malaria cases were predicted to rise dramatically during COVID-19, but thanks to the unwavering efforts of malaria control programs and health care workers, the global community held the line. The recently released WHO World Malaria Report 2021 highlights this incredible collective achievement and makes clear the need for better tools, faster regulatory approval processes, and renewed commitments to make new progress against one of the world’s oldest diseases.

Mosquito nets get a refresh

Making measurable gains in malaria reduction across all endemic countries requires refocused commitments and clear prioritization of new innovations. Global health agencies Unitaid and The Global Fund to Fight AIDS, Tuberculosis and Malaria have made such a commitment by supporting the New Nets Project. Led by the Innovative Vector Control Consortium, the New Nets Project pilots new tools to strengthen the insecticide-treated net (ITN) market. ITNs, when draped over beds or sleeping areas as protection against mosquitoes, are one of the very best tools in the fight against malaria. And now, ITNs have gotten a much-needed refresh through the incorporation of chemical synergists, substances that make current insecticides more effective against resistance, and new active ingredients that kill mosquitoes resistant to pyrethroid, a common insecticide class.

Dr. Adama Gansane, principal investigator for the New Nets Project in Burkina Faso, highlights the toll resistance has taken: “With around 12 million malaria cases yearly and high levels of mosquito resistance to current insecticides, Burkina Faso urgently needs new and effective tools.”

The coordinated efforts of New Nets Project partners and others have brought these new tools to market and helped reduce barriers to access. As a core member of the project team responsible for the design and implementation of evidence pilots, PATH partnered with the national malaria control programs in Burkina Faso, Mozambique, Nigeria, and Rwanda, research institutions in sub-Saharan Africa, and collaborators across the globe to measure and document the effectiveness of these new ITNs in real-world implementation settings.

Our methods, including surveys, mosquito surveillance, and anthropological inquiry, complement ongoing cluster randomized controlled trials and leverage country-led disease and mosquito surveillance systems. More details can be found in a recent publication in Malaria Journal by Gansané, Candrinho, Mbituyumuremyi, et al., and in previous publications by Propopoff et al. on the effectiveness of ITNs with chemical synergists and by Monroe et al. on the importance of human-mosquito interaction.

Interim results show promise

Though work remains to be done to understand the cost-effectiveness of these new ITN types in various malaria-endemic contexts, we are pleased to share widely the interim analyses that illustrate their potential effectiveness. The report shows that, while an increase in access to and use of any type of mosquito net can reduce malaria transmission, districts where the synergist piperonyl butoxide or dual active ingredient ITNs were distributed have seen greater reductions in malaria compared to districts where standard ITNs were distributed.

Across settings in West, Central, and Southern Africa, these new ITNs have reduced the malaria burden and brought real gains to malaria control programs fighting to reduce child mortality and illness. For example, according to Dr. Baltazar Candrinho, project director for Mozambique’s National Malaria Control Program, “We distributed dual active ingredient ITNs in Mozambique’s Niassa and Manica Districts in 2020. While the impact of the ITNs is being evaluated by the New Nets Project, the reduction in malaria cases has been approximately 50 percent according to the official national data.”

“The reduction in malaria cases has been approximately 50 percent according to the official national data.”
— Dr. Baltazar Candrinho, National Malaria Control Program, Mozambique

As Pedro Saide, the Changara District focal point in Mozambique put it, “Hardly anyone comes to the clinic with malaria anymore. You don’t have to show me data. I know that it has worked.”

We are sharing this interim report now because we share a responsibility and a commitment to getting actionable data out quickly and widely. The interim report is not intended as the final analysis; pilots will be completed by the end of 2022 and additional research will continue under The Global Fund’s Net Transition Initiative.

As new data become available, we will incorporate them into subsequent reports. We expect that these results will complement the results from concurrent randomized control trials from additional New Nets Project partners and together the data will inform a World Health Organization policy decision. Pilot study outcomes will be critical to understanding the public health value of nets with synergists or new active ingredients in different settings, which will inform decisions about where to best place different types of nets.

We will send an invitation in the new year to a webinar at which national malaria program directors will share findings and give participants a chance to ask questions. As we move toward a renewed commitment to malaria control and elimination worldwide, we celebrate new innovations and committed partners.

Read More