With the recent changes in the climate, most species of plants and animals are evolving to adapt to their surroundings. Recently, researchers at the Liverpool School of Tropical Medicine have identified a new mechanism in Anopheles mosquitoes that makes them invincible.
WHAT ARE Anopheles MOSQUITOES?
Anopheles is a genus of mosquitoes with over 460 species and was first described by German entomologist J.W. Meigen in 1818. The Anopheles mosquitoes are notoriously known for being carriers of the single-celled parasite called Plasmodium, which causes malaria. However, not all species of Anopheles are carriers of Plasmodium. In fact, out of 460 species, only 100 species of Anopheles are carriers, and one of the most famous species is the Anopheles gambiae.
The research team closely observed two of the most abundant malaria carriers in West Africa: the Anopheles gambiae and the Anopheles coluzzii and found that there are abundant amounts of binding protein situated in the legs of these mosquitoes that make them invulnerable to insecticide.
ARE Anopheles MOSQUITOES CAPABLE TO SURVIVE INSECTICIDE?
In a press release issued by the Liverpool School of Tropical Medicine, Dr. Victoria Ingham says: "We have found a completely new insecticide resistance mechanism that we think is contributing to the lower than expected efficacy of bed nets." Dr. Ingham explains that the research team found a family of binding proteins located at the legs of both two Anopheles species, which makes them resistant to insecticide.
According to Dr. Ingham, the protein which is based in the mosquitoes legs is coming into direct contact with the insecticide as soon as the mosquito lands on the bed net. On a lighter note, these findings provide good news as it gives researchers an idea on how to effectively prevent diseases like malaria carried by these insecticide-resistant mosquitoes.
WHAT MAKES THE Anopheles MOSQUITO RESISTANT TO INSECTICIDES?
Dr. Victoria Ingham and her team of researchers analyzed the two species of Anopheles and found that the binding protein called SAP2 was abundant in insecticide-resistant mosquito populations at becomes more effective when SAP2 came in contact with pyrethroids, a type of insecticide commonly used in bed nets. In the experiment, the researchers discovered that when SAP2 is reduced through partial silencing of the gene, the resistance to pyrethroids is also reduced.
Entomologists noted an increase in a mosquito's ability to resist insecticides across different populations, and this discovery has led to the development of bed nets that are treated with the synergist piperonyl butoxide along with pyrethroid - the former aims to attack the most widespread and potent resistance mechanisms produced by cytochrome P405. However, mosquitoes are quick to adapt and evolve more resistance mechanisms challenging scientists to identify additional synergists that can restore the insect's susceptibility.
According to senior author Professor Hilary Ranson, long-lasting insecticide-treated bed nets remain one of the key interventions in malaria control. "It is vital that we understand and mitigate resistance within the mosquito population in order to ensure that the dramatic reductions in disease rates in previous decades are not reversed." Professor Ranson explains that the newly discovered resistance mechanism can provide scientists with a paramount target for monitoring the resistance and the development of compounds that are able to block pyrethroid resistance. The findings of this research are published in Nature.
