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

UN: 1 Million Somalis at Risk of Hunger

Group warns region is in dire need of humanitarian aid, with at least 200,000 children under age of five acutely malnourished as drought hits southern, central part of nation More

Human Rights Groups Allege Supression of Freedoms in Thailand

Thailand’s military, police have suppressed release of independent report assessing human rights in kingdom during first 100 days of latest coup More

Jennifer Lawrence Contacts FBI After Nude Photos Hacked

'Silver Linings Playbook' actress' photos were posted on image-sharing forum 4chan; Federal Bureau of Investigations is looking into matter 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.
Ukraine Schools Resume Classes, Donate to Government Forcesi
X
September 02, 2014 12:58 PM
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 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 Internet, Technology Offer New Tools for Journalists

The Internet and rapidly evolving technology is quickly changing how people receive news and how journalists deliver it. There are now more ways to tell a story than ever before. One school in Los Angeles is teaching the next generation of journalists with the help of a state-of-the-art newsroom. Elizabeth Lee has this report.
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.
Video

Video Cost to Raise Child in US Continues to Rise

The cost of raising a child in the United States continues to rise. In its latest annual report, the U.S. Department of Agriculture says middle income families with a child born in 2013 can expect to spend more than $240,000 before that child turns 18. And sending that child to college more than doubles that amount. VOA’s Deborah Block visited with a couple with one child in Alexandria, Virginia, to learn if the report reflects their lifestyle.
Video

Video Chaotic Afghan Vote Recount Threatens Nation’s Future

Afghanistan’s troubled presidential election continues to be rocked by turmoil as an audit of the ballots drags on. The U.N. says the recount will not be completed before September 10. Observers say repeated disputes and delays are threatening the orderly transfer of power and could have dangerous consequences. VOA correspondent Meredith Buel reports.

AppleAndroid