WHO approves spatial repellents for malaria control: What it is and how it works
The World Health Organization (WHO) has approved a new way to fight malaria: spatial repellents. These compact devices slowly release mosquito-repelling chemicals into the air and are meant to be used alongside insecticide-treated nets. Unlike traditional tools, spatial repellents offer protection when people are moving inside their homes – not just when sleeping under a bed net. This news signals a major leap in malaria prevention, offering extra protection in places where mosquitoes resist conventional methods.
What are spatial repellents, and how do they work?
Spatial repellents, also called spatial emanators, are small sheets or mesh panels that you hang indoors, typically on walls. They gradually release volatile chemicals into the air that repel or even kill mosquitoes, keeping them from entering the space or biting occupants. Because they act through the air, they do not require physical contact with mosquitoes like treated nets do.Trials have shown that when used together with bed nets, spatial repellents can reduce malaria cases by about one-third.In mid-August this year, the WHO issued a conditional recommendation supporting the use of spatial repellents alongside insecticide-treated nets (ITNs) to control malaria in regions with ongoing transmission. This is the first new malaria control tool endorsed by WHO in decades. WHO issued a conditional recommendation for using spatial repellents alongside insecticide-treated nets. It also prequalified two products: Mosquito Shield and Guardian by SC Johnson & Son, which means aid agencies can purchase them for deployment in affected areas. These represent the first new class of vector control tools in decades, marking a significant advancement in malaria prevention.
What are the benefits of spatial repellents?
Consistent, round-the-clock protection: Unlike bed nets that only work at night, spatial repellents provide continuous indoor protection, including when people are awake and moving around.Easy to deploy: Lightweight and compact, these devices are easy to hang; no electricity or heat is needed.Adaptable to resistance: Since they don’t touch humans directly, chemicals can be quickly updated if mosquitoes develop resistance.Versatile settings: Especially useful in places where nets or sprays are hard to use, such as humanitarian camps, public spaces, or urban areas lacking proper infrastructure.Long duration: Some versions, like Guardian, can last up to one year, offering long-term protection.Is it all perks and no cons?Turns out that’s not true.
What are the limitations?
Not a standalone fix yet: Its efficacy alone is still under study. WHO recommends using spatial repellents along with existing tools, not as replacements.Risk of net abandonment: Some people may stop using bed nets after installing spatial repellents, potentially reducing overall protection.Environmental and disposal concerns: Improper disposal could harm the environment. Proper messaging and disposal protocols are essential.Research gaps: Effectiveness in outdoor settings and emergencies is still being studied.Despite those few gaps, the spatial repellent has already achieved significant success in the Kenya trial, as in Busia County, the use of Mosquito Shield™ reduced malaria infection by about 33% among children aged 6 months to 10 years old.Furthermore, Unitaid has committed US$18 million through its CANVeCT project to study standalone efficacy and use in humanitarian settings, led by research partners in Cameroon, the UK, and beyond. In addition, SC Johnson, after over a decade of R&D, has ramped up production, launching new manufacturing in Kenya and Argentina to support mass distribution.
