Researchers determine how mosquitoes survive dengue virus infection

Feb 13, 2009

Colorado State University researchers have discovered that mosquitoes that transmit deadly viruses such as dengue avoid becoming ill by mounting an immediate, potent immune response. Because their immune system does not eliminate the virus, however, they are able to pass it on to a new victim.

In a study published February 13 in the open-access journal PLoS Pathogens, the researchers show that RNA interference - the mosquito immune response -- is initiated immediately after they ingest blood containing dengue virus, but the virus multiplies in the mosquitoes nevertheless.

Dengue fever and dengue hemorrhagic fever are major global public health burdens, with up to 100 million cases occurring annually, yet no vaccines or specific preventative medicines are currently available. The Aedes aegypti mosquito transmits dengue virus. Determining how the virus evades the mosquito's defense is an important next step in research that aims to fight disease by interrupting the growth of dengue virus within the mosquito before it can be transmitted.

RNA interference is an evolutionarily ancient antiviral defense used by mosquitoes and other invertebrates to destroy the RNA of many invading arthropod-borne viruses. This team of researchers previously showed that ramping up the RNA interference response in mosquitoes prevented dengue infection, and now they show that temporarily impairing this immune response increased virus transmission.

The investigators analyzed RNA from adult mosquitoes, finding that both the trigger and initiator molecules for RNA interference were formed after infection, yet viral RNA could readily be detected in the same mosquitoes. They also measured infectious virus rates in the mosquitoes' saliva, which revealed levels whereby the mosquitoes could transmit the disease to humans.

These findings indicate that genetic manipulation of RNA interference could be a significant weapon in stopping dengue virus transmission by Aedes aegypti.

Sa´nchez-Vargas I, Scott JC, Poole-Smith BK, Franz AWE, Barbosa-Solomieu V, et al. (2009) Dengue Virus Type 2 Infections of Aedes aegypti Are Modulated by the Mosquito's RNA Interference Pathway. PLoS Pathog 5(2): e1000299. doi:10.1371/journal.ppat.1000299 dx.plos.org/10.1371/journal.ppat.1000299

Source: Public Library of Science

Explore further: Researchers bring clean energy a step closer

add to favorites email to friend print save as pdf

Related Stories

Rapid test kit detects dengue antibodies from saliva

Jan 29, 2015

Finding out whether you have been infected with dengue may soon be as easy as spitting into a rapid test kit. The Institute of Bioengineering and Nanotechnology (IBN) of A*STAR has developed a paper-based ...

Charting Colorado's vulnerability to climate change

Feb 05, 2015

Sea-level rise may not be eating away at Colorado's borders, but climate change exposes other critical vulnerabilities in the state, according to a new report. Rising temperatures likely will take a toll ...

GMO mosquito plan sparks outcry in Florida

Jan 31, 2015

A British company's plan to unleash hordes of genetically modified mosquitoes in Florida to reduce the threat of dengue fever and other diseases has sparked an outcry from fearful residents.

Recommended for you

Researchers bring clean energy a step closer

5 hours ago

For nearly half a century, scientists have been trying to replace precious metal catalysts in fuel cells. Now, for the first time, researchers at Case Western Reserve University have shown that an inexpensive metal-free catalyst ...

The construction of ordered nanostructures from benzene

10 hours ago

A way to link benzene rings together in a highly ordered three-dimensional helical structure using a straightforward polymerization procedure has been discovered by researchers from RIKEN Center for Sustainable ...

Superatomic nickel core and unusual molecular reactivity

10 hours ago

A superatom is a combination of two or more atoms that form a stable structural fragment and possess unique physical and chemical properties. Systems, that contain superatoms, open a number of amazing possibilities ...

Oat breakfast cereals may contain a common mold-related toxin

Feb 25, 2015

Oats are often touted for boosting heart health, but scientists warn that the grain and its products might need closer monitoring for potential mold contamination. They report in ACS' Journal of Agricultural and Food Chemistry that s ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.