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

Photogallery South Africa Bans Travelers From Ebola-stricken Countries

South Africans returning from affected West African countries will be thoroughly screened, required to fill out medical questionnaire, health minister says More

Multimedia UN Launches ‘Biggest Aid Operation in 30 Years’ in Iraq

Move aims to help thousands of Iraqi religious minorities who fled their homes as Kurdish, Iraqi government forces battle Sunni insurgents More

Video African Media Tries to Educate Public About Ebola

IT specialists, together with radio and TV reporters, are battling misinformation and prejudice about disease 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.
Gaza Conflict, Hamas Popularity Challenge Abbasi
X
Scott Stearns
August 21, 2014 9:20 PM
The Palestinian unity government of Mahmoud Abbas has failed to convince Hamas to agree to Egyptian-negotiated terms with Israel on a Gaza cease-fire. VOA State Department Correspondent Scott Stearns reports on what the Gaza conflict means for President Abbas, with whom U.S. officials have worked for years on a two-state solution to the Israeli-Palestinian conflict.
Video

Video Gaza Conflict, Hamas Popularity Challenge Abbas

The Palestinian unity government of Mahmoud Abbas has failed to convince Hamas to agree to Egyptian-negotiated terms with Israel on a Gaza cease-fire. VOA State Department Correspondent Scott Stearns reports on what the Gaza conflict means for President Abbas, with whom U.S. officials have worked for years on a two-state solution to the Israeli-Palestinian conflict.
Video

Video Nigeria's 'Nollywood' Movie Industry Rolls in High Gear

Twenty years after its birth in a video shop in Lagos, Nigeria's "Nollywood" is one of the most prolific film industries on earth. Despite low budgets and whirlwind production schedules, Nigerian films are wildly popular in Africa and industry professionals say they hope, in the future, their films will be as great in quality as they are in quantity. Heather Murdock has more for VOA from Lagos.
Video

Video UN Launches 'Biggest Aid Operation in 30 Years' in Iraq

The United Nations has launched what it describes as one of the biggest aid operations in 30 years in northern Iraq, as hundreds of thousands of refugees flee the extremist Sunni militant group calling itself the Islamic State. As Kurdish and Iraqi forces battle the Sunni insurgents, the fighting has forced more people to flee their homes. Kurdish authorities say the international community must act now to avert a humanitarian catastrophe. Henry Ridgwell reports for VOA from London.
Video

Video Cambodian American Hip Hop Artist Sings of Personal Struggles

A growing underground movement of Cambodian American hip hop artists is rapping about the struggles of living in urban America. Most, if not all of them, are refugees or children of refugees who came to the United States from Cambodia to escape the Khmer Rouge genocide of the 1970s. Through their music, the artists hope to give voice to immigrants who have been struggling quietly for years. Elizabeth Lee reports from Long Beach, California.
Video

Video African Media Tries to Educate Public About Ebola

While the Ebola epidemic continues to claim lives in West Africa, information technology specialists, together with radio and TV reporters, are battling misinformation and prejudice about the disease - using social media to educate the public about the deadly virus. VOA’s George Putic has more.
Video

Video Ferguson Calls for Justice as Anger, Violence Grips Community

Violence, anger and frustration continue to grip the small St. Louis suburb of Ferguson, Missouri. Protests broke out after a white police officer fatally shot an unarmed black teenager on August 9. The case has sparked outrage around the nation and prompted the White House to send U.S. Attorney Eric Holder to the small community of just over 20,000 people. VOA’s Mary Alice Salinas has more from Ferguson.
Video

Video Beheading Of US Journalist Breeds Outrage

U.S. and British authorities have launched an investigation into an Islamic State video showing the beheading of kidnapped American journalist James Foley by a militant with a British accent. The extremist group, which posted the video on the Internet Tuesday, said the murder was revenge for U.S. airstrikes on militant positions in Iraq - and has threatened to execute another American journalist it is holding. Henry Ridgwell has more from London.
Video

Video Family Robots - The Next Big Thing?

Robots that can help us with daily chores like cooking and cleaning are a long way off, but automatons that serve as family companions may be much closer. Researchers in the United States, France, Japan and other countries are racing to build robots that can entertain and perform some simpler tasks for us. VOA’s George Putic reports.
Video

Video In Ukraine, Fear and Distrust Remain Where Fighting has Stopped

As the Ukrainian military reclaims control of eastern cities from pro-Russian separatists, residents are getting a chance to rebuild their lives. VOA's Gabe Joselow reports from the town of Kramatorsk in Donetsk province, where a sense of fear is still in the air, and distrust of the government in Kyiv still runs deep.
Video

Video Five Patients Given Experimental Ebola Drug Said to Be Improving

The World Health Organization has approved the use of experimental treatments for Ebola patients in West Africa. The Ebola outbreak there is unprecedented, the disease deadly. The number of people who have died from Ebola has surpassed 1,200. VOA's Carol Pearson reports on the ethical considerations of allowing experimental drugs to be used.
Video

Video China Targets Overseas Assets of Corrupt Officials

As China presses forward with its anti-graft effort, authorities are targeting corrupt officials who have sent family members and assets overseas. The efforts have stirred up a debate at home on exactly how many officials take that route and how likely it is they will be caught. Rebecca Valli has this report.
Video

Video Leading The Fight Against Islamic State, Kurds Question Iraqi Future

Western countries including the United States have begun arming the Kurdish Peshmerga forces in northern Iraq to aid their battle against extremist Sunni militants from the Islamic State. But there are concerns that a heavily-armed Kurdistan Regional Government, or KRG, might seek to declare independence and cause the break-up of the Iraqi state. As Henry Ridgwell reports from London, the KRG says it will only seek greater autonomy from Baghdad.
Video

Video In Rural Kenya, Pressure Builds Against Female Circumcision

In some Kenyan communities, female genital mutilation remains a rite of passage. But activists are pushing back, with education for girls and with threats of punishment those who perform the circumcision. Mohammed Yusuf looks at the practice in the rural eastern community of Tharaka-Nithi.

AppleAndroid