News / Health

Researchers Develop Simple Test for River Blindness

Jessica Berman
Diagnosing the tropical parasitic illness Onchocerciasis, also known as river blindness, might soon be as easy as testing a urine sample. Such a simple test would permit more effective diagnosis and treatment of a disease that now afflicts nearly 18 million people around the world.

People call Onchocerciasis "river blindness" because it’s caused by the bite of a parasitic-worm-infected black fly that lives near rivers. The illness is most common in sub-Saharan Africa, although it also exists in parts of Yemen and in Central and South America.

The river blindness parasite has an active and inactive phase, making it difficult to treat the disease.  During its active phase, the female worm produces millions of microscopic eggs that migrate to different tissues throughout the body. Infection of the eyes can lead to blindness.

The disease is usually treated with the antiparasitic agent Ivermectin, which lowers the number of eggs produced by the worm, and an antibiotic, doxycycline, which sterilizes it.  

But according to Daniel Globisch, a researcher at Scripps Research Institute in California, it is difficult to determine when the worm is active. That information would help health care providers know whether their treatment is effective or not. It would also reduce the risk that wasteful use of antibiotics might promote drug resistance in the river blindness parasite.

Currently, Globisch says, the only way is to be certain that the worm is active is to do a skin biopsy to look for signs of the parasite.

“This is very invasive and also painful and really uncomfortable for the people. And that’s why a non-invasive diagnostic is as important,” Globisch said.

Globisch and colleagues think they found one. They have identified a single biomarker produced by the worm - a chemical that sends signals from one nerve cell to another - that is present in the patient's urine during the active phase.

“The single marker is linked to the worm’s lifecycle. And that is why we believe this is the perfect marker to get a test,” Globisch said.

Globisch says the test would be inexpensive and portable. Infected individuals also suffer severe itching and the Scripps scientists are investigating treatments to ease that symptom for as long as patients with river blindness harbor the parasite.

An article on a urine test for river blindness is published in the journal Proceedings of the National Academy of Sciences.

You May Like

Video Russia’s Syrian Escalation Tests Obama’s Crisis Response

Critics once again question whether president has been slow to act on Syrian conflict, thus creating opening for powers like Russia More

Ancient African DNA Shows Mass Migration Back Into Africa

First genetic analysis of ancient human remains in Africa suggests massive migration from north around time of Egyptian empire More

NASA: Pluto Has Blue Sky

New photos also reveal the presence of water ice More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Hungary Criticized for Handling of Refugeesi
Henry Ridgwell
October 08, 2015 8:02 PM
Amnesty International has accused Hungary of breaking multiple international and European human rights laws in its handling of the refugee crisis. As Henry Ridgwell reports, thousands of migrants and refugees continue to travel through the Balkans to Hungary every day.

Video Hungary Criticized for Handling of Refugees

Amnesty International has accused Hungary of breaking multiple international and European human rights laws in its handling of the refugee crisis. As Henry Ridgwell reports, thousands of migrants and refugees continue to travel through the Balkans to Hungary every day.

Video Iraqi-Kurdish Teachers Vow to Continue Protest

Sixteen people were injured when police used tear gas and rubber bullets to disperse teachers and other public employees who took to the streets in Iraq’s Kurdish north, demanding their salaries from the Kurdish Regional Government (KRG). VOA’s Dilshad Anwar, in Sulaimaniya, caught up with protesting teachers who say they have not been paid for three months. Parke Brewer narrates his report.

Video Syrian Village Community Faces Double Displacement in Lebanon

Driven by war from their village in southwestern Syria, a group of families found shelter in Lebanon, resettling en masse in a half-built university to form one of the biggest settlements of its kind in Lebanon. Three years later, however, they now face being kicked out and dispersed in a country where finding shelter as a refugee can be especially tough. John Owens has more for VOA from the city of Saida, also known as Sidon.

Video Bat Colony: Unusual Tourist Attraction in Texas

The action hero Batman might be everyone’s favorite but real bats hardly get that kind of adoration. Put more than a million of these creatures of the night together and it only evokes images of horror. Sarah Zaman visited the largest urban bat colony in North America to see just how well bat and human get along with each other.

Video Device Shows Promise of Stopping Motion Sickness

It’s a sickening feeling — the dizziness, nausea and vomiting that comes with motion sickness. But a device now being developed could stop motion sickness by suppressing certain signals in the brain. VOA’s Deborah Block reports.

Video Making a Mint

While apples, corn, and cranberries top the list of fall produce in the US, it’s also the time to harvest gum, candy, and toothpaste—or at least the oil that makes them minty fresh. Erika Celeste reports from South Bend, Indiana on the mint harvest.

Video Activists Decry Lagos Slum Demolition

Acting on a court order, authorities in Nigeria demolished a slum last month in the commercial capital, Lagos. But human rights activists say the order was illegal, and the community was razed to make way for a government housing project. Chris Stein has more from Lagos.

Video TPP Agreed, But Faces Stiff Opposition

President Barack Obama promoted the Trans-Pacific Partnership on Tuesday, one day after 12 Pacific Rim nations reached the free trade deal in Atlanta. The controversial pact that would involve about 40 percent of global trade still needs approval by lawmakers in respective countries. Zlatica Hoke reports Obama is facing strong opposition to the deal, including from members of his own party.

Video Ukranian Artist Portrays Putin in an Unusual Way

As Russian President Vladimir Putin was addressing the United Nations in New York last month, he was also being featured in an art exhibition in Washington. It’s not a flattering exhibit. It’s done by a Ukrainian artist in a unique medium. And its creator says it’s not only a work of art - it’s a political statement. VOA’s Tetiana Kharchenko has more.

Video Nano-tech Filter Cleans Dirty Water

Access to clean water is a problem for hundreds of millions of people around the world. Now, a scientist and chemical engineer in Tanzania (in East Africa) is working to change that by creating an innovative water filter that makes dirty water safe. VOA’s Deborah Block has the story.

Video Demand Rising for Organic Produce in Cambodia

In Cambodia, where rice has long been the main cash crop, farmers are being encouraged to turn to vegetables to satisfy the growing demand for locally produced organic farm products. Daniel de Carteret has more from Phnom Penh.

Video Botanists Grow Furniture, with Pruning Shears

For something a bit out of the ordinary to furnish your home, why not consider wooden chairs, crafted by nature, with a little help from some British botanists with an eye for design. VOA’s Jessica Berman reports.

VOA Blogs