News / Health

Genetically-Modified Mosquito Can't Transmit Malaria

But major obstacles remain before 'malaria-proof' is released from lab

Under UV light, this mosquito larva reveals a red fluorescent marker in its nervous system, causing eyes and nerves to glow. The marker's presence tells the researchers in Riehle's team that this individual carries the genetic construct rendering it immun
Under UV light, this mosquito larva reveals a red fluorescent marker in its nervous system, causing eyes and nerves to glow. The marker's presence tells the researchers in Riehle's team that this individual carries the genetic construct rendering it immun

Multimedia

Audio
Art Chimes

Malaria kills about a million people each year, mostly children in Africa.

Efforts to combat the disease have centered on controlling the mosquito that transmits the malaria parasite. Bed nets and eradication programs have had success, but now a team of U.S. researchers is trying a different approach — a genetically modified mosquito that can not transmit the disease.

University of Arizona scientist Michael Riehle explains that as the malaria parasite reproduces inside the mosquito, there is one part of the parasite's life cycle when it is particularly vulnerable.

"We're targeting the malaria parasites as they travel across the midgut," he explained. "And we chose that because that's the stage where the fewest number of malaria parasites are present."

Only a few dozen of the plasmodium parasites, in fact. Unless they're stopped, they would eventually multiply in the thousands to infect the next person bit by the mosquito.

Michael Riehle, holding genetically altered mosquitoes, and his team work in a highly secure lab environment to prevent genetically altered mosquitoes from escaping.
Michael Riehle, holding genetically altered mosquitoes, and his team work in a highly secure lab environment to prevent genetically altered mosquitoes from escaping.

So Riehle and his colleagues developed a genetic modification that disrupts some key functions in the mosquito, including its immune response and lifespan. The modified mosquitoes die sooner, meaning they have less time to bite a new victim and transmit malaria. More importantly, the genetic changes kill the parasites in the midgut.

But Riehle admits, they don't know exactly why.

"One of the things we want to know is definitely how this is working. We have some ideas as to how the parasite's being killed, but we really don't know at this point. And so future studies are going to figure out what exactly this gene is doing in there to kill the malaria parasite. And that should help us generate an even more effective malaria-proof mosquito."

If they succeed, a malaria-proof mosquito could be a powerful weapon in the fight against a killer disease assuming it can actually be deployed.

Riehle says the engineered mosquito would have to be further modified to displace the mosquitoes that carry malaria.

"And the idea is, you give the mosquitoes some sort of mechanism that gives them a competitive advantage in the wild. Therefore, when you release them, the mosquitoes can out-compete the wild mosquitoes, and over time, over a period of several years, actually replace the population."

Creating a genetically-modified mosquito to prevent malaria transmission is one thing; modifying it to drive the existing mosquitoes to extinction may be another. And University of Arizona scientist Michael Riehle admits there are, as he put it, "a number of hurdles" to overcome. In any event, he says it will be at least 10 years before the genetically modified mosquitoes might be ready to leave the lab.

He describes this novel way of preventing the spread of malaria in the journal PloS Pathogens.

You May Like

EU Court Fines Poland for Hosting CIA 'Black Sites'

Ruling is first time a court has acknowledged suspects were held and tortured at the sites, under US program launched following the 9/11 terrorist attacks More

Migrant Issues Close to Home Spur Groups to Take Action

Groups placing water, food in the desert, or aiding detainees after release, have one common goal: no more deaths of migrants crossing illegally into the US More

Video At AIDS Conference, Prevention Pill Stirs Excitement

Truveda shows promise, spurring debate over access and other approaches More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Israel Targets Gaza Supply Tunnelsi
X
July 24, 2014 4:42 AM
The Israeli military has launched a ground operation in Gaza to destroy the myriad tunnels that may have been used to smuggle weapons to Hamas. VOA's Zlatica Hoke reports that could mean more hardship for the people of Gaza, who obtain some of their essential supplies through these underground passages
Video

Video Israel Targets Gaza Supply Tunnels

The Israeli military has launched a ground operation in Gaza to destroy the myriad tunnels that may have been used to smuggle weapons to Hamas. VOA's Zlatica Hoke reports that could mean more hardship for the people of Gaza, who obtain some of their essential supplies through these underground passages
Video

Video MH17's 'Black Boxes' Could Reveal Crash Details

The government of Malaysia now has custody of the cockpit voice and flight data recorders from Malaysia Airlines Flight 17, which was hit by a missile over Ukraine before crashing last week. As VOA's Carolyn Presutti reports, the so-called black boxes may hold information about the final minutes of the flight.
Video

Video Living in the Shadows Panel Discussion

Following a screening of the new VOA documentary, "AIDS - Living in the Shadows," at the World AIDS conference in Melbourne, a panel discussed the film and how to combat the stigma associated with HIV/AIDS.
Video

Video IAEA: Iran Turns its Enriched Uranium Into Less Harmful Form

Iran has converted its stockpiles of enriched uranium into a less dangerous form that is more difficult to use for nuclear weapons, according to the United Nations’ Atomic Energy Agency. The move complies with an interim deal reached with Western powers on Iran's nuclear program last year, in exchange for easing of sanctions. Henry Ridgwell reports for VOA from London.
Video

Video Relic of Saint Draws Catholics Worried About Immigration Issue

A Roman Catholic saint who is a figure of devotion for those crossing the border into the United States is attracting believers concerned about the plight of undocumented immigrants. Mike O'Sullivan reports from Los Angeles, where a relic of Saint Toribio has drawn thousands to local churches.
Video

Video US Awards Medal of Honor for Heroics in Bloodiest of Afghan Battles

U.S. combat troops are withdrawing from Afghanistan, on pace to leave the country by the end of this year. But on Monday, U.S. President Barack Obama took time to honor a soldier whose actions while under fire in Afghanistan earned him the Medal of Honor. VOA's Jeff Seldin has more from the Pentagon.
Video

Video Ukraine Rebels Surrender MH17 Black Boxes

After days of negotiations, a senior separatist leader handed over two black boxes from an airliner downed over eastern Ukraine to Malaysian experts early Tuesday. While on Monday, the U.N. Security Council unanimously demanded that armed groups controlling the crash site allow safe and unrestricted access to the wreckage.
Video

Video In Cambodia, HIV Diagnosis Brings Deadly Shame

Although HIV/AIDS is now a treatable condition, a positive diagnosis is still a life altering experience. In Cambodia, people living with HIV are often disowned by friends, family and the community. This humiliation can be unbearable. We bring you one Cambodian woman’s struggle to overcome a life tragedy and her own HIV positive diagnosis.

AppleAndroid