After 100 years, hope of a new vaccine against TB

New Delhi: A new vaccine against tuberculosis could be available in eight years. Currently, the only available vaccine for the prevention of TB is Bacille-Calmette-Guérin (BCG), which was discovered almost 100 years ago.      Saying the world was finally waking up to the need for an effective new-age TB vaccine, the World Health Organization on Thursday announced that 11 vaccine candidates were undergoing phase-1 or phase-2 trials for TB prevention while one immunotherapeutic vaccine was being put through phase-3 trial. The WHO said, "It is hoped that one or two of the candidates currently undergoing phase- 2 trial will enter a phase-3 trial over the next three years, with the possibility of licensing at least one new vaccine by 2020."      A new vaccine that prevents tuberculosis could significantly reduce the huge financial burden of treating drug-resistant TB, which can cost Rs 1 lakh a patient in India, which is home to about 73,000 drug-resistant TB patients. It can also prevent the toll the disease takes on patients who are subjected to 18-24 months of strong medications with side effects that can be as severe as hearing loss or psychosis.  Only 1.6% of MDR TB patients enrolled      In a shocking disclosure, the World Health Organization on Thursday said while India has 73,000 patients with multi-drug resistant TB (MDR TB)—the highest in the world—just about 1.6% of the affected people had enrolled for treatment. P 17 2 approaches being used to develop TB vaccines: WHO  New Delhi: A new vaccine to prevent tuberculosis (TB) is expected in about eight years and it may come as a boon for India, which is home to a big number of people suffering from the deadly airborne disease.      In 2011, there were an estimated 8.7 million new cases of TB and 1.4 million people died from the disease, including one million deaths among HIV-negative individuals and 4.3 lakh among people who were HIV-positive. TB is one of the top killers of women, with 3 lakh deaths among HIV-negative women and 2 lakh mortalities among those HIV-positive last year.      BCG vaccine protects against severe forms of TB in children, but its efficacy in preventing pulmonary TB in adults is highly variable. BCG is also not recommended for use in infants known to be infected with HIV due to the risk of disseminated BCG disease.      WHO says that two different approaches are being used to develop TB vaccines. The first approach is to develop vaccines that will do better than BCG and replace it — such as an improved version of BCG or a new attenuated live M tuberculosis vaccine.      The second approach is to develop a "prime-boost" strategy in which BCG continues to be given to neonates (as now) since it prevents TB in infants and children, and giving the new vaccine as a "booster" dose at a later stage.