For decades, chemical pesticides have been the most important means of controlling insects such as mosquitoes that transmit malaria to humans. Unfortunately, mosquitoes have countered and evolved genetic shields have allowed mosquitoes to protect themselves and their offspring against future attacks.

In an article published in Parasitology Trends, a series of fascinating genetic changes that confer mosquito resistance are summarized. The paper was written by postdoctoral researcher Colin Camden and two colleagues at the Department of Entomology at the University of California, Riverside. These findings highlight the interplay between human interventions, mosquito evolution and disease outcomes and will help scientists develop new strategies to overcome pesticide resistance.According to the World Health Organization, there are about 212 million malaria cases by 2015, with an estimated 429,000 deaths from malaria. Although global prevention and control measures have reduced global malaria mortality by 29% since 2010, the increase in drug-resistant insects underscores the need for a new strategy. "One of the major barriers to the eradication of malaria is the enormous diversity and adaptability of the mosquito Anopheles mosquito so the genes, behavioral and ecological factors that better understand its resistance to evolutionary ability are key to controlling this disease," said Card Muden said.

In sub-Saharan Africa, a number of factors, including the widespread use of long-acting insecticidal nets, indoor spray-in, chemical pollutant exposure, urbanization and agricultural practices, have led the malaria mosquito species to have developed altitude Resistant.Camden's article highlights several ways mosquitoes can adapt to pesticide exposure. A favorable mutation of the target site of the insecticide is a major source of resistance, highlighting the direct impact of human intervention on the mosquito genome. Other mutations increase the activity of the enzyme before it degrades or isolates the insecticide from reaching the cellular target. In some cases, mosquitoes change behavior and avoid contact with pesticides.

Camden said: "These changes occur at the molecular, physiological and behavioral levels, but there are often multiple changes that, with the availability of DNA sequencing, are now at the genome level to identify these evolutionary changes.Camden said the high genetic diversity among mosquito species and their ability to exchange genes make it hard to stop the development of pesticide-resistant populations. Gene-driven systems use genetic means to kill mosquitoes, prevent them from multiplying or prevent them from spreading the parasites that cause malaria, but are under development, but what worries people is that mosquitoes may also become resistant to these technologies. Camden said: "The insights gained from the intensive use of pesticides and their impact on mosquito genomes are crucial to the successful implementation of gene editing systems as a new method of controlling mosquito-borne diseases due to the emergence of mosquito-borne diseases such as walrus , Some countries are implementing them on a large scale or are preparing to deploy vector control strategies. One of the most pressing needs is to design evidence-based surveillance tools to fight the inevitable resistance of mosquitoes. "