News / Health

    Researchers Warn Against TB Drug-Resistance

    A patient who tested positive for extreme drug resistant tuberculosis awaits treatment at a rural hospital at Tugela Ferry in South Africa's impoverished KwaZulu Natal province, (File photo).
    A patient who tested positive for extreme drug resistant tuberculosis awaits treatment at a rural hospital at Tugela Ferry in South Africa's impoverished KwaZulu Natal province, (File photo).
    Jessica Berman
    Studies show a short course of an inexpensive anti-tuberculosis drug can dramatically reduce transmission of the bacterial respiratory disease.  That's why many public health experts promote the use of the single antibiotic - called isoniazid - in communities with large populations of HIV-infected individuals -- people with notoriously high rates of secondary TB infections.  Researchers, however, caution that widespread use of isoniazid could speed the emergence of drug-resistant strains of TB. 

    The World Health Organization recommends giving a six-month course of isoniazid preventive therapy (IPT) to three groups of people at risk of becoming infected with tuberculosis and spreading it to others.  Included were individuals infected with HIV, the virus that causes AIDS; children under the age of five with immature immune systems; and people who have been exposed to tuberculosis and test positive for the disease.

    In studies using short course anti-TB therapy, results have been impressive, according to Mario Raviglione, director of the World Health Organization’s Stop-TB office.

    Raviglione says IPT suppresses TB infection in 60 to 70 percent of HIV-negative individuals and 80 to 90 percent of those with HIV.

    “You just don’t become infectious to others and [you] yourself are not affected by the disease,” he said.

    Despite the demonstrated effectiveness of isoniazid preventative therapy, Raviglione says it’s rarely used.  He notes that IPT is limited to about 400,000 HIV-infected individuals, a fraction of the eight million people living with HIV globally who are at highest risk of becoming infected with TB.  And he says the single-drug therapy is almost never used in children or others exposed to TB.

    But with an estimated one-third of the world’s population infected with a latent form of TB that could become active -- and lethal -- at any time, some international public health officials have proposed using isoniazid prophylaxis, or prevention, in entire at-risk communities throughout the developing world.

    Others, like Caroline Colijn, think such widespread use of isoniazid mono-therapy to contain TB is potentially too risky.  

    Colijn, of Imperial College London, and colleagues constructed a mathematical model that shows how blanketing a community with a single anti-TB drug, such as isoniazid in IPT, paves the way for the eventual emergence of drug-resistant strains of the TB bacterium.

    “We don’t argue against doing IPT.  It’s probably one of the best interventions we have against TB," he noted. "But we would definitely argue that we need to consider these long-term consequences and roll out appropriate treatment for resistant TB and treatment for TB.”

    The WHO’s Raviglione agrees, saying the key to a successful tuberculosis prevention strategy is making sure people who are actively infected with TB are not treated with a single drug.

    “This mathematical model doesn’t change our concern because we knew if you are not doing a proper job in screening out, in ruling out, active tuberculosis when you start prophylaxis, then you run the concrete risk of developing drug resistance in that very person,” he explained.

    An article describing the risks of promoting drug-resistant forms of tuberculosis with the widespread use of Isoniazid Preventive Therapy against TB appears in the journal Science Translational Medicine.

    You May Like

    Top US General: Turkish Media Report ‘Absurd'

    General Dunford rejects ‘irresponsible' claims of coup involvement by former four-star Army General Campbell, who led NATO forces in Afghanistan before retiring earlier this year

    Video Saving Ethiopian Children Thought to Be Cursed

    'Omo Child' looks at efforts of one African man to stop killings of ‘mingi’ children

    Protests Over Western Troops Threaten Libyan 'Unity' Government

    Fears mount that Islamist foes of ‘unity' government plan to declare a revolutionaries' council in Tripoli

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    London’s Financial Crown at Risk as Rivals Eye Brexit Opportunitiesi
    X
    VOA News
    July 25, 2016 5:09 PM
    By most measures, London rivals New York as the only true global financial center. But Britain’s vote to leave the European Union – so-called ‘Brexit’ – means the city could lose its right to sell services tariff-free across the bloc, risking its position as Europe’s financial headquarters. Already some banks have said they may shift operations to the mainland. Henry Ridgwell reports from London.
    Video

    Video London’s Financial Crown at Risk as Rivals Eye Brexit Opportunities

    By most measures, London rivals New York as the only true global financial center. But Britain’s vote to leave the European Union – so-called ‘Brexit’ – means the city could lose its right to sell services tariff-free across the bloc, risking its position as Europe’s financial headquarters. Already some banks have said they may shift operations to the mainland. Henry Ridgwell reports from London.
    Video

    Video Recycling Lifeline for Lebanon’s Last Glassblowers

    In a small Lebanese coastal town, one family is preserving a craft that stretches back millennia. The art of glass blowing was developed by Phoenicians in the region, and the Khalifehs say they are the only ones keeping the skill alive in Lebanon. But despite teaming up with an eco-entrepreneur and receiving an unexpected boost from the country’s recent trash crisis the future remains uncertain. John Owens reports from Sarafand.
    Video

    Video Migrants Continue to Risk Lives Crossing US Border from Mexico

    In his speech Thursday before the Republican National Convention, the party’s presidential candidate, Donald Trump, reiterated his proposal to build a wall along the U.S.-Mexico border if elected. Polls show a large percentage of Americans support better control of the nation's southwestern border, but as VOA’s Greg Flakus reports from the border town of Nogales in the Mexican state of Sonora, the situation faced by people trying to cross the border is already daunting.
    Video

    Video In State of Emergency, Turkey’s Erdogan Focuses on Spiritual Movement

    The state of emergency that Turkish President Recep Tayyip Erdogan has declared is giving him even more power to expand a purge that has seen an estimated 60,000 people either arrested or suspended from their jobs. VOA Europe correspondent Luis Ramirez reports from Istanbul.
    Video

    Video Calm the Waters: US Doubles Down Diplomatic Efforts in ASEAN Meetings

    The United States is redoubling diplomatic efforts and looking to upcoming regional meetings to calm the waters after an international tribunal invalidated the legal basis of Beijing's extensive claims in the South China Sea. VOA State Department correspondent Nike Ching has the story.
    Video

    Video Four Brother Goats Arrive in Brooklyn on a Mission

    While it's unusual to see farm animals in cities, it's become familiar for residents of Brooklyn, New York, to see a little herd of goats. Unlike gas-powered mowing equipment, goats remove invasive weeds quietly and without adding more pollution to the air. As Faiza Elmasry tells us, this is a pilot program and if it proves to be successful, the goat gardener program will be extended to other areas of New York. Faith Lapidus narrates.
    Video

    Video Scientists in Poland Race to Save Honeybees

    Honeybees are in danger worldwide. Causes of what's known as colony collapse disorder range from pesticides and loss of habitat to infections. But scientists in Poland say they are on track to finding a cure for one of the diseases. VOA’s George Putic reports.
    Video

    Video Wall Already Runs Along Parts of US-Mexico Border

    The Republican Party’s presidential nominee, Donald Trump, gained the support of many voters by saying he would build a wall to keep undocumented immigrants and drugs from coming across the border from Mexico. Critics have called his idea impractical and offensive to Mexico, while supporters say such a bold approach is needed to control the border. VOA’s Greg Flakus has more from the border town of Nogales, Arizona.
    Video

    Video New HIV Tests Emphasize Rapid Results

    As the global fight against AIDS intensifies, activists have placed increasing importance on getting people to know their HIV status. Some companies are developing new HIV testing methods designed to be quick, easy and accurate. Thuso Khumalo looks at the latest methods, presented at the International AIDS conference in Durban, South Africa.
    Video

    Video African Youth with HIV Urge More Support

    HIV, the virus that causes AIDS, is the top killer of teens in sub-Saharan Africa. But many youths say their experience with the virus is unique and needs to be addressed differently than the adult epidemic. VOA South African Correspondent Anita Powell reports.
    Video

    Video Pop-Up Art Comes to Your Living Room, Backyard and Elsewhere

    Around the world, independent artists and musicians wrestle with a common problem: where to exhibit or perform? Traditional spaces such as museums and galleries are reserved for bigger names, and renting a space is not feasible for many. Enter ArtsUp, which connects artists with venue owners. Whether it’s a living room, restaurant, office or even a boat, pop-up events are bringing music and art to unexpected places. Tina Trinh has more.
    Video

    Video Scotland’s Booming Whisky Industry Fears Brexit Hangover

    After Britain’s vote to leave the European Union, Scotland’s government wants to break away from the United Kingdom – fearing the nation’s exports are at risk. Among the biggest of these is whisky. Henry Ridgwell reports on a time of turmoil for those involved in the ancient art of distilling Scotland’s most famous product.

    Special Report

    Adrift The Invisible African Diaspora