Fears of "Extreme" TB Strain
    By Robin McKie
    The Observer UK

    Sunday 03 September 2006

New drug-resistant infection is "nightmare" say health experts.

    Health experts are to hold an emergency meeting in Johannesburg this week, following the discovery of a deadly new strain of tuberculosis.

    The strain - known as extreme drug-resistant TB - has horrified World Health Organisation doctors. In one outbreak in South Africa, 52 of 53 patients died within weeks of becoming infected.

    "This new strain leaves us facing a nightmare,' said Paul Nunn, coordinator of the WHO's drug-resistance unit. "It is resistant to nearly every drug in our arsenal. We are now on the threshold of the appearance of a strain of TB that is resistant to every medicine known to science."

    The strain was originally discovered by scientists earlier this year. They looked at cases of multiple drug-resistant TB - which has developed over the past decade in many parts of the world - and discovered that among these a worrying new "extreme" strain had evolved.

    "Mainstream drugs are ineffective against multiple drug-resistant TB," said Nunn. "However, there are half a dozen second-line medicines that can be used to tackle it. Now this new extreme resistant strain has appeared. It is not only resistant to our principal anti-TB drugs, but to many of our second-line defences. In short, we are now on the last line of our defences against tuberculosis."

    Among the areas found to have been affected by extreme drug-resistant TB are Latvia and South Africa. Scientists discovered the strain last month among HIV-infected patients in the Kwazulu-Natal region. "Fifty two of the 53 infected people are already dead, and the last may well have died by now," added Nunn.

    An estimated 4.5 million people in South Africa have HIV. Extreme drug-resistance TB could devastate the population. "If countries don't have the diagnostic capacity to find these patients, they will die without proper treatment," said Nunn.

    As a result, WHO is to hold its emergency meeting in Johannesburg to help establish measures that will lead to the rapid diagnosis of the new strain.

    "It appears to kill within a few weeks and that does not give us a lot of time to spot it and treat it with the right drugs," added Nunn. The few classes of drugs that are still effective against this strain of TB are expensive and can be toxic.

    The meeting will be attended by officials from WHO and its partners, including the South African Medical Research Council and the US Centers for Disease Control and Prevention.