News / Africa

Tough TB Responds to Drug Treatment

A young patient with potentially fatal MDR TB in isolation in a hospital in South Africa (Photo: D.Taylor)
A young patient with potentially fatal MDR TB in isolation in a hospital in South Africa (Photo: D.Taylor)

Multimedia

Audio
Joe DeCapua
An antibiotic used to treat severe infections shows promise against a very resistant and deadly form of tuberculosis. XDR-TB is resistant to at least four of the drugs used most often against the disease.


Extensively drug resistant tuberculosis – or XDR-TB – is still considered rare, although cases have been reported in nearly 80 countries. Health officials believe the number of XDR-TB cases is underreported because there’s no specific test for it.

It can be cured, but the odds against that happening are often quite high. It can kill quickly, especially if a person is co-infected with HIV, the virus that causes AIDS.

Dr. Ray Chen, a staff clinician at the National Institute of Allergy and Infectious Diseases, says XDR-TB is the next step after MDR-TB, or multi-drug resistant tuberculosis, which is a lot more common.

“That’s been a known problem for many years, primarily as a result of people who don’t take their drugs well. And then the tuberculosis bug slowly develops resistance to the drugs that are used,” he said.

MDR-TB is resistant to two of the top line drugs used for standard tuberculosis therapy. When the disease becomes resistant to two additional first-line drugs, it’s upgraded to XDR-TB.

“It came to world attention in 2006 in a study in South Africa where a number of patients were found to have this extensive resistance to tuberculosis drugs, and they had a very high mortality rate. And so it became recognized as a major problem for tuberculosis,” he said.

In fact, the mortality rate was as high at 90 percent in patients also infected with HIV.

Standard TB treatment can take up to six months. MDR-TB treatment can last between 18 and 24 months.

So researchers knew that more drugs were needed to tackle the various forms of TB.  They had heard of some informal studies using the drug linezolid on TB patients with some success. But there was no formal study.

Linezolid is a drug that’s already on the market and it’s approved for the use of resistant bacteria, which we call gram-positive bacteria that don’t respond to typical antibiotics.

To find out, researchers tested linezolid on 41 patients with XDR-TB. The patients already had been treated for six months with the best TB drugs available, but failed to respond. Chen said linezolid was added to their regimen.

“We found that adding the linezolid had a significant effect and that most of the patients converted their sputum from showing tuberculosis to not having tuberculosis in the sputum by six months. About 87 percent of the patients became negative for tuberculosis within six months. So it showed a very good response,” he said.

That’s the good news. The bad news is many of the patients suffered severe side effects. These include nerve problems with hands and feet going numb. There were also eye problems and abnormalities with red and white blood cells. Use of the drug was stopped before any of the patients suffered permanent damage.

As a result, Chen said more studies are needed to determine whether it can safely be used on a large-scale in combination with other drugs. He also says new, potent antibiotics will be coming on the market and these may be tested on TB, as well.

You May Like

Video For West Ukraine City, Conflict Far Away Yet Near

Physically and culturally close to Western Europe, Lviv feels solidarity with compatriots in country’s east but says they need to decide own future More

West African Women Disproportionately Affected by Ebola

Women's roles in families and the community put them at greater risk for contracting the disease, officials say More

Video NASA's MAVEN Spacecraft Arrives at Mars

Mars Atmosphere and Volatile Evolution craft will measure rates at which gases escape Martian atmosphere into space More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
NASA’s MAVEN Probe Enters Mars Orbiti
X
September 22, 2014 9:20 PM
NASA’s newest Mars probe, called MAVEN, has successfully entered its designated orbit around the Red Planet. Scientists will use its sophisticated instruments to try to learn what happened to the atmosphere Mars had a few billion years ago. VOA’s George Putic has more.
Video

Video NASA’s MAVEN Probe Enters Mars Orbit

NASA’s newest Mars probe, called MAVEN, has successfully entered its designated orbit around the Red Planet. Scientists will use its sophisticated instruments to try to learn what happened to the atmosphere Mars had a few billion years ago. VOA’s George Putic has more.
Video

Video For West Ukraine City, Conflict Far Away Yet Near

The western Ukrainian city of Lviv prides itself on being both physically and culturally close to Western Europe. The Russian-backed separatists in the eastern part of the country are 1,200 kilometers away, and seemingly even farther away in their world view. Still, as VOA’s Al Pessin reports, the war is having an impact in Lviv.
Video

Video Saving Global Fish Stocks Starts in the Kitchen

With an estimated 90 percent of the world’s larger fish populations having already vanished, a growing number of people in the seafood industry are embracing the concept of sustainable fishing and farming practices. One American marine biologist turned restaurateur in Thailand is spreading the word among fellow chefs and customers. VOA Correspondent Steve Herman reports from Bangkok.
Video

Video Chinese Admiral Key in China’s Promotion of Sea Links

China’s President last week wrapped up landmark visits to India, Sri Lanka and Maldives, part of a broader campaign to promote a new “Maritime Silk Road” in Asia. The Chinese government’s promotion efforts rely heavily on the country’s best-known sailor, a 15th century eunuch named Zheng He. VOA's Bill Ide reports from the sailor’s hometown in Yunnan on the effort to promote China’s future by recalling its past.
Video

Video Experts Fear Ebola Outbreak ‘Beyond Our Capability to Contain’

Each day brings with it new warnings about the deadly Ebola outbreak already blamed for killing more than 2,600 people across West Africa. And while countries and international organizations like the United Nations are starting to come through on promises of help for those most affected, the unprecedented speed with which the virus has spread is raising questions about the international response. VOA's Jeff Seldin has more from Washington.
Video

Video Natural Gas Export Plan Divides Maryland Town

A U.S. power company that has been importing natural gas now wants to export it. If approved, its plant in Lusby, Maryland, would likely be the first terminal on the United States East Coast to export liquefied natural gas from American pipelines. While some residents welcome the move because it will create jobs, others oppose it, saying the expansion could be a safety and environmental hazard. VOA’s Deborah Block examines the controversy.
Video

Video Difficult Tactical Battle Ahead Against IS Militants in Syria

The U.S. president has ordered the military to intensify its fight against the Islamic State, including in Syria. But how does the military conduct air strikes in a country that is not a U.S. ally? VOA correspondent Carla Babb reports from the Pentagon.
Video

Video Iran, World Powers Seek Progress in Nuclear Talks

Iran and the five permanent members of the U.N. Security Council plus Germany, known as the P5 + 1, have started a new round of talks on Iran's nuclear program. VOA State Department correspondent Pam Dockins reports that as the negotiations take place in New York, a U.S. envoy is questioning Iran's commitment to peaceful nuclear activity.
Video

Video Migrants Caught in No-Man's Land Called Calais

The deaths of hundreds of migrants in the Mediterranean this week has only recast the spotlight on the perils of reaching Europe. And for those forunate enough to reach a place like Calais, France, only find that their problems aren't over. Lisa Bryant has the story.
Video

Video Westgate Siege Anniversary Brings Back Painful Memories

One year after it happened, the survivors of the terror attack on Nairobi's Westgate Shopping Mall still cannot shake the images of that tragic incident. For VOA, Mohammed Yusuf tells the story of victims still waiting for the answer to the question 'how could this happen?'
Video

Video Whaling Summit Votes to Uphold Ban on Japan Whale Hunt

The International Whaling Commission, meeting in Slovenia, has voted to uphold a court ruling banning Japan from hunting whales in the Antarctic Ocean. Conservationists hailed the ruling as a victory, but Tokyo says it will submit revised plans for a whale hunt in 2015. Henry Ridgwell reports from London.
Video

Video A Dinosaur Fit for Land and Water

Residents and tourists in Washington D.C. can now examine a life-size replica of an unusual dinosaur that lived almost a hundred million years ago in northern Africa. Scientists say studying the behemoth named Spinosaurus helps them better understand how some prehistoric animals adapted to life on land and in water. The Spinosaurus replica is on display at the National Geographic museum. VOA’s George Putic has more.
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