The findings, published in the journal Nature Communications, could lead to new ways to control the spread of dengue virus, which infects an estimated 390 million people worldwide each year.
Dengue virus is spread by mosquitoes of the Aedes genus. When a mosquito bites an infected person, it ingests the virus along with blood. The virus then replicates in the mosquito's midgut, and can be transmitted to other people when the mosquito bites again.
However, not all mosquitoes that ingest the dengue virus become infected. Some mosquitoes are able to resist the infection, and these mosquitoes are known as refractory.
The researchers found that refractory mosquitoes have a higher level of a certain type of protein called ferritin in their midgut. Ferritin is a protein that stores iron, and it is thought that the high levels of ferritin in refractory mosquitoes help to protect them from the dengue virus.
The researchers also found that refractory mosquitoes have a lower level of a certain type of sugar called trehalose in their midgut. Trehalose is a sugar that is thought to help the dengue virus replicate, and the low levels of trehalose in refractory mosquitoes may help to prevent the virus from replicating.
The researchers believe that the high levels of ferritin and the low levels of trehalose in refractory mosquitoes work together to protect them from the dengue virus. These findings could lead to new ways to control the spread of dengue virus, such as developing drugs that target ferritin or trehalose in mosquitoes.
"Understanding the mechanisms that allow some mosquitoes to resist dengue infection opens new avenues for innovative approaches to control dengue transmission," said study author Maria V. Dengue-Muller, Ph.D., of the National Institute of Allergy and Infectious Diseases (NIAID), part of NIH.
