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

Video Experts Warn World Losing Ebola Fight

Doctors Without Borders says world is losing battle against Ebola, unless wealthy nations dispatch specialized biological disaster response teams More

Video Experts: Rise of Islamic State Significant Development in Jihadism

Many analysts contend the group - which grew out of al-Qaida in Iraq - has been rebuilding for years More

US-Based Hong Kongers Pledge Support for Pro-Democracy Activists

Democracy advocates call on Chinese living abroad to join them in opposing new election rules for their home territory 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.
Larger Than Life Chinese Lanterns Make Southern California Appearancei
X
Elizabeth Lee
September 02, 2014 8:57 PM
Chinese lanterns with a long history are lighting up in 21st century style at the Los Angeles County Fair in southern California. Visitors can see traditional lanterns that hang, but also lanterns in the shape of animals, iconic landmarks and many other objects, all created by artisans from a place in China known for its lanterns. Elizabeth Lee has the details from the fair in the city of Pomona.
Video

Video Larger Than Life Chinese Lanterns Make Southern California Appearance

Chinese lanterns with a long history are lighting up in 21st century style at the Los Angeles County Fair in southern California. Visitors can see traditional lanterns that hang, but also lanterns in the shape of animals, iconic landmarks and many other objects, all created by artisans from a place in China known for its lanterns. Elizabeth Lee has the details from the fair in the city of Pomona.
Video

Video Experts See Rise of ISIS as Significant Development

The Islamic State’s rise seems sudden. It caught the U.S. by surprise this summer when it captured large portions of northern Iraq and spread its wings in neighboring Syria. But many analysts contend that the group - which grew out of al-Qaida in Iraq - has been rebuilding for years. VOA's Jela de Franceschi takes a closer look at the rise of ISIS and its implications for the Middle East and beyond.
Video

Video Israel Concerned Over Syrian Rebels in Golan

Israeli officials are following with concern the recent fighting between Syrian rebels and government forces near the contested Golan Heights. Forty-four U.N. peacekeepers from Fiji have been seized by Syrian Islamist rebels and the clashes occasionally have spilled into Israel. VOA’s Scott Bobb reports from Jerusalem.
Video

Video Ukraine Schools Resume Classes, Donate to Government Forces

A new school year has started in Ukraine but thousands of children in the war-torn east are unable to attend because of ongoing clashes with pro-Russia rebels. In Ukraine's capital, patriotic education has become the norm along with donations to support injured security forces fighting to take back rebel-held areas. VOA's Daniel Schearf reports from Kyiv.
Video

Video US Detainees Want Negotiators for Freedom in North Korea

The three U.S. detainees held in North Korea were permitted to speak with foreign media Monday. The government of Kim Jong Un restricted the topics of the questions, and the interviews in Pyongyang were limited to five minutes. Each of the men asked Washington to send a representative to Pyongyang to secure his release. VOA’s Carolyn Presutti has our story.
Video

Video Turkmen From Amerli Describe Survival of IS Siege

Over the past few weeks, hundreds of Shi'ite Turkmen have fled the town of Amerli seeking refuge in the northern city of Kirkuk. Despite recent military gains after U.S. airstrikes that were coordinated with Iraqi and Kurdish forces, the situation remains dire for Amerli’s residents. Sebastian Meyer went to Kirkuk for VOA to speak to those who managed to escape.
Video

Video West Africa Ebola Vaccine Trials Possible by Early 2015

A U.S. health agency is speeding up clinical trials of a possible vaccine against the deadly Ebola virus that so far has killed more than 1,500 people in West Africa. If successful, the next step would be a larger trial in countries where the outbreak is occurring. VOA's Carol Pearson has more.
Video

Video Survivors Commemorate 70th Anniversary of Nazi Liquidation of Jewish Ghetto

When the German Nazi army occupied the Polish city of Lodz in 1939, it marked the beginning of a long nightmare for the Jewish community that once made up one third of the population. Roughly 200,000 people were forced into the Lodz Ghetto. Less than 7,000 survived. As VOA’s Kane Farabaugh reports, some survivors gathered at the Union League Club in Chicago on the 70th anniversary of the liquidation of the Lodz Ghetto to remember those who suffered at the hands of the Nazi regime.

AppleAndroid