Drug-resistant TB's prevalence a growing concern

Members of the media met on Monday as part of a background briefing on the growing issue of multi-drug resistant tuberculosis.

Tim McHugh, a professor of medical microbiology with University College London, said that multiple factors led to the growth of multi-drug resistant tuberculosis over the years. The factors include a lack of international interest in TB after the 1950s, globalization and the side effects of current drugs.

The side effects that result from TB drugs cause some patients to stop taking the drugs when symptoms subside. By not completing a full course of treatment, the TB can become resistant to the drug.

McHugh said that going forward, TB must be stopped using a combination of vaccines and drugs.

Ann Ginsberg, the consulting editor of the journal Tuberculosis, said that the last decade or so has seen a lot of stimulation to the TB vaccination effort. Within the last 10 years alone, 12 new vaccine candidates began testing through clinic and human trials. Ginsberg said that each round of experiments will build on the last to create the most effective vaccine.

According to Ginsberg, even a vaccine with a 60 percent efficacy rate could decrease incidence of the disease by 50 percent.

Ginsberg noted Bacille Calmette-Guerin, a TB vaccine that has been used by doctors for the last 90 years. The BCG vaccine is effective against TB in infants but not as effective for TB in the lungs.

MVA85A, however, is a vaccine that, when combined with BCG, strengthens T calls against TB in the immune system. Helen McShane, a professor of vaccinology at the University of Oxford, developed the MVA85A vaccine, which should have trial results by the first quarter of 2013.

Attendees at the meeting included Mark Hennessy of the Irish Times, Elizabeth Blunt from IRIN News, Leigh Phillips of Nature, Tom Feilden from BBC Radio 4, Geoff Watts from BMJ, Trish Reece from BBC News, John von Radowitz from PA, Helen Albert from MedWire News, Keith Alcorn from NAM, Clive Cookson from FT, James Gallagher from BBC News and Hacene Zitouni from MBC News.