News / Health

Wind Offers Clue to Curbing Malaria

Study: targeting larval pools downwind from malaria hotspots could help control disease

Malaria is transmitted among humans by female Anopheles mosquitoes like this one.
Malaria is transmitted among humans by female Anopheles mosquitoes like this one.

Multimedia

Audio
Rosanne Skirble

A new malaria prevention strategy might literally be blowing in the wind.

A team of scientists studying the patterns of malaria infection in rural Kenyan villages noticed that, despite a gradual reduction of malaria cases in the region, “hotspots” persisted.



The blood-sucking mosquitos that transmit the malaria parasite to humans breed in water.

So the researchers decided to examine the location of those breeding ponds in relation to the most infected villages. Their findings are published this week in Nature Communications.

Co-author David Smith, an epidemiologist with the Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland, says a curious pattern emerged.

“In this study what we did is we looked at the locations of aquatic habitats and the locations of humans and we were trying to find out if there was some kind of clustering, which there should be and of course there was. But as we looked even closer what we found was that there was an association between the direction of the wind and the location of where people were at risk.”

Smith says while mosquitos aren’t particularly good flyers, their flight pattern is directed by the scent of a potential human host.

This mosquito larval habitat in Kilifi, Kenya, is also used for domestic purposes such as washing.
This mosquito larval habitat in Kilifi, Kenya, is also used for domestic purposes such as washing.

“We had a hypothesis that since scents travel down wind, that the mosquitos were actually tacking across the wind until they found one of those odor plumes and then tacking upwind until they found it. We should expect to find that places with higher risk were upwind of larval habitat.”  

Smith and his research team studied 642 children living in Kenyan villages after the rainy season, when malaria peaks.

Janet Midega is a medical entomologist with the Kenya Medical Research Institute and co-author of the study. She says scientists compared the malaria case data with the proximity of stagnant water pools. “What we did find was a lot of the pools of water did have immature mosquito stages, and so we sampled these pools of water. We sampled these mosquitos and identified them as the mosquito species that is responsible for malaria transmission in the area.”  

The study found that the shorter the distance from those larval incubators, the higher the prevalence of malaria.  

Smith says factoring wind into the equation makes it possible to target larval pools downwind from malaria hotspots and so control the disease at its source.

“And the philosophy here is just that knowing it better we might be able to predict the distribution of risk a little bit better, or at least understand what mosquitos are doing so that we can do a better job of distributing nets or interventions.”

Co-author Janet Midega says while plans are already underway to expand the study in Kenya, replicating it elsewhere presents an obvious challenge.  

“The applicability of the outcome of these results will be extremely dependent on the local conditions and the mosquitos that are common in that local environment so that control measures are tailored for the local epidemiological situation.”

So, Midega says, prevention strategies will depend on where you live, as some 30 to 40 different mosquito species transmit malaria.  Almost half the world’s population - about 3.3 billion people - is at risk.  In fact, the mosquito-borne parasitic disease strikes some 250 million people every year, and results in nearly one million deaths, largely in sub-Saharan Africa.

You May Like

Karzai's Legacy: Missed Opportunities?

Afghanistan's president leaves behind a much different nation than the one he inherited, yet his legacy from 13 years in power is getting mixed reviews More

US Secret Service Head: White House Security Lapse 'Unacceptable'

Julia Pierson faces tough questions from lawmakers after a recent intrusion at the White House: 'It is clear that our security plan was not executed properly' More

Frustrated, Liberian Students Want Ebola Fight Role

Thousands have volunteered to go to counties, rural villages to talk to people in their language about deadly virus 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.
Malaysia Struggles to Stop People Joining Jihadi
X
Mahi Ramakrishnan
September 30, 2014 2:16 PM
Malaysian authorities say militant groups like the so-called "Islamic State" have used social media to entice at least three dozen Malaysian Muslims to fight in what they call "jihad" in Syria and Iraq. As Mahi Ramkrishnan reports from Kuala Lumpur, counterterrorism police are deeply worried about what could happen when these militants return home.
Video

Video Malaysia Struggles to Stop People Joining Jihad

Malaysian authorities say militant groups like the so-called "Islamic State" have used social media to entice at least three dozen Malaysian Muslims to fight in what they call "jihad" in Syria and Iraq. As Mahi Ramkrishnan reports from Kuala Lumpur, counterterrorism police are deeply worried about what could happen when these militants return home.
Video

Video Could US Have Done More to Stop Rise of Islamic State?

President Obama says airstrikes against Islamic State militants in Syria will likely continue for some time because, in his words, "there is a cancer that has grown for too long." So what if President Obama had acted sooner in Syria to arm more-moderate opponents of both the Islamic State and the Syrian government? VOA State Department Correspondent Scott Stearns reports from the United Nations.
Video

Video Treasure Hunters Seek 'Hidden Treasure' in Central Kenya

Could a cave in a small village in central Kenya be the site of buried treasure? A rumor of riches, left behind by colonialists, has some residents dreaming of wealth, while others see it as a dangerous hoax. VOA's Gabe Joselow has the story.
Video

Video Iran's Rouhani Skeptical on Syria Strikes

Iranian President Hassan Rouhani expressed skepticism Friday that U.S.-led airstrikes in Iraq and Syria could crush Islamic State militants. From New York, VOA’s Margaret Besheer reports the president was also hopeful that questions about Iran’s nuclear program could be resolved soon.
Video

Video US House Speaker: Congress Should Debate Authorization Against IS

As wave after wave of U.S. airstrikes target Islamic State militants, the speaker of the Republican-controlled House of Representatives says he would be willing to call Congress back into session to debate a formal, broad authorization for the use of military force. VOA’s Michael Bowman reports from Washington, where legislators left town 10 days ago for a seven-week recess.
Video

Video Ebola Patients Find No Treatment at Sierra Leone Holding Center

At a holding facility in Makeni, central Sierra Leone, dozens of sick people sit on the floor in an empty university building. They wait in filthy conditions. It's a 16-hour drive by ambulance to Kailahun Ebola treatment center. Adam Bailes was there and reports on what he says are some of the worst situations he has seen since the beginning of this Ebola outbreak. And he says it appears case numbers may already be far worse than authorities acknowledge.
Video

Video Identifying Bodies Found in Texas Border Region

Thousands of immigrants have died after crossing the border from Mexico into remote areas of the southwestern United States in recent years. Local officials in south Texas alone have found hundreds of unidentified bodies and buried them in mass graves in local cemeteries. Now an anthropologist and her students at Baylor University have been exhuming bodies and looking for clues to identify them. VOA’s Greg Flakus has more from Waco, Texas.
Video

Video Ebola Robs Liberians of Chance to Say Good-Bye to Loved Ones

In Liberia, where Ebola has killed more than 1,500 people, authorities have worked hard to convince people to allow specialized burial teams to take away dead bodies. But these safety measures, while necessary, make it hard for people to say good bye to their loved ones. VOA's Anne Look reports on the tragedy from Liberia.
Colonel Steve ‘Spiros’ Pisanos left Greece and came to the U.S. to learn to fly. He flew fighters for the Allies in World War II, narrowly escaping death multiple times.Colonel Steve ‘Spiros’ Pisanos left Greece and came to the U.S. to learn to fly. He flew fighters for the Allies in World War II, narrowly escaping death multiple times.

AppleAndroid