Scientific News

Malaria discovered on the salivary gland of mosquitoes

There is a sort of “bottleneck” in the body of the mosquitoes that cause malaria and that causes the parasites of this disease are not transmitted all over the body of people when mosquitoes bite them.

The discovery was made by a group of scientists from the Johns Hopkins School of Medicine that parasites inside mosquitoes are stopped by a “road block” during their escape attempt in the insect’s salivary glands during the sting. It is estimated that less than a tenth of the parasites present in the mosquito’s salivary gland at the time of puncture is transmitted into the body of humans, as stated by Michael Wells, a researcher engaged in the study.

The researchers analyzed, in particular, the salivary gland of the Anopheles mosquito. This gland is made up of three lobes of cells that produce saliva enclosed in a sort of protective film called the basement membrane. The parasites, to enter the body of humans, must cross this membrane, penetrate into a layer of salivary cells and then “swim” in an area called the secretory cavity to finally reach the salivary duct. Researchers have discovered that few manage to reach the latter conduit.

This discovery could naturally serve to devise new strategies to reduce malaria infection, one of the most serious diseases, especially in the tropical and subtropical regions of the world, as well as one of the most widespread so that it is estimated that there are 220 million people who they have contracted all over the world. It could also serve as regards the contrast to other diseases transmitted by the same mosquitoes, first of all Zika fever.

Deborah Andrew, professor of cell biology at Johns Hopkins University and one of the main authors of the study, comments as follows: “Our results add substantial details to the role of mosquito salivary glands as access organs to diseases spread by them insects. By improving the transmission barriers that naturally exist in mosquitoes, we can potentially block the spread of malaria and other deadly mosquito-borne diseases, such as Zika fever.”