Ground zero: Mosquito gut may hold key to preventing dengue, Zika
A mosquito’s ability to replicate and transmit a virus depends on the environment of tissues in its midgut and may hold the key to preventing mosquito-borne diseases like Zika and dengue, a study has found.
The midgut is the primary site of infection, according to the researchers. By targeting the sphingolipid pathway, which links together several pathways important for cell signalling and subcellular structure that are altered by virus infection, researchers could devise strategies that stall viral replication in the mosquito and prevent its transmission to humans.
“The strategies that are being pursued right now often involve sterilising mosquitoes or eradicating them, and those might work, but a subtler way would be simply changing the ability of the virus to exploit a pathway and let the mosquito continue on like nothing happened,” said Richard Kuhn, from Purdue University in the US.
“It’s fairly common these days to alter the expression of genes, so we might be able to create a different form of the enzyme that is not susceptible to virus manipulation,” Kuhn said.
Arboviruses move between mosquitoes (or ticks) and hosts. After an infected mosquito bites a host, the host comes down with the disease, and eventually another mosquito bites the host, picks up the disease in its blood meal and the cycle continues.
When a mosquito is infected, its metabolism changes to accommodate the virus. In the case of Aedes aegypti, the “yellow fever mosquito,” there are big fluctuations in molecules that function as membrane building blocks, energy storage molecules and intermediates in lipid production.
These changes could be a result of cellular resources being redistributed for viral replication, the cellular response to infection, or both. The consequences for mosquitoes aren’t totally clear.
“There is a lot we don’t know about the ‘cost’ to the vector, but there is no argument there is one,” said Catherine Hill, a researcher at Purdue. Hindustan Times