Scientists reveal a surprisingly simple potential solution to malaria
Researchers at the University of Texas at El Paso have discovered that adding liquid soap to some insecticides can significantly enhance their effectiveness against malaria-carrying mosquitoes. This breakthrough offers a promising approach to combating mosquitoes’ increasing resistance to current insecticides. The research aims to develop an insecticidal formulation of soap for internal use in areas where malaria is widespread, which could affect millions affected by this deadly disease.
Could the solution to the long-term battle against malaria be as straightforward as using soap? This interesting possibility was presented in a recent study published in PLOS Neglected tropical diseases By scientists from the University of Texas at El Paso.
The team found that adding small amounts of liquid soap to some classes of insecticides can increase their effectiveness more than tenfold.
This finding is promising news as malaria-carrying mosquitoes are showing increasing resistance to current insecticides, said Collins Kamdam, lead author of the study and an assistant professor in UTEP’s Department of Biological Sciences.
“Over the past two decades, mosquitoes have become highly resistant to most insecticides,” Kamdem said. “It is now a race to develop alternative compounds with new modes of action.”
Alternative pesticides and field trials
Laboratory tests and field trials have shown that neonicotinoids, a special class of insecticides, are a promising alternative for target populations that show resistance to existing insecticides, said Carolyn Voigt, an assistant research professor at UTEP and the study’s second author. However, neonicotinoids do not kill some mosquito species Classify Unless its effectiveness is enhanced. In this case, Voigt said, the soap is the reinforcement.
University of Texas at El Paso scientists Collins Camdem, Ph.D., left, and Carolyn Voigt, Ph.D., have discovered that adding small amounts of liquid soap to some classes of insecticides can boost their effectiveness by more than tenfold. Credit: University of Texas at El Paso
Malaria is a devastating mosquito-borne disease that spreads across sub-Saharan Africa, Asia, and Latin America. It causes fever, fatigue, headache, and chills; The disease can be fatal. In 2020, there were an estimated 241 million cases of malaria worldwide, according to the Centers for Disease Control, resulting in 627,000 deaths.
Discovering the effectiveness of soap in Cameroon
Prior to joining UTEP, Kamdem worked at the Cameroon Center for Research in Infectious Diseases (CRID); It was there that the first people discovered the effectiveness of soap during a routine test for pesticides.
Current World Health Organization (WHO) protocols for testing mosquitoes’ susceptibility to certain insecticides recommend adding a seed oil-based product to insecticide mixtures. Kamdim noted that when the compound was added, the mosquito mortality rate increased compared to using the insecticide alone.
“This compound belongs to the same class of substances as kitchen soap,” Kamdim said. “We thought: Why not test products that have the same properties?”
He and his team selected three low-cost linseed oil-based soaps common in sub-Saharan Africa — Maitre Savon de Marseille, Caroline Savon Noir, and La Perdrex Savon — and added them to four different neonicotinoids, acetamiprid and clothianidin. Imidacloprid and thiamethoxam.
The intuition paid off. In all cases, the insecticides greatly enhanced their effectiveness, the team wrote in the study. “The three brands of soap increased the mortality rate from 30 percent to 100 percent compared to using pesticides alone,” said Ashu Farid, first author of the study and a Ph.D. Student at the University of Yaounde, Cameroon.
Further research and potential applications
The team also tested adding soap to a class of insecticides known as pyrethroids. But in those cases, they didn’t see any benefits.
The team hopes to conduct additional tests to determine the amount of soap needed to enhance the insecticide.
“We would like to create an insecticidal soap formula that can be used indoors in Africa and is healthy for users,” Kamdem said. “There is something unknown about whether this formulation will adhere to materials such as mosquito nets, but the challenge is both promising and very exciting.”
Reference: “Vegetable oil-based surfactants are adjuvants that enhance the efficacy of neonicotinoid insecticides and can bias susceptibility testing in adult mosquitoes” by Fred A. Asho, Carolyn Voigt, and Marilyn M. Ambadiang, Veronique Pinlap-Peng, and Collins Camdem, November 17, 2023, PLOS Neglected tropical diseases.
DOI: 10.1371/journal.pntd.0011737
Additional authors on the study are doctoral student Marilyn M. Ambadiang of CRID and the University of Yaoundé and Professor Veronique Pinlap Peng, Ph.D., of the University of Yaounde.
The project was supported by a grant from National Institutes of Health.
