Preliminary testing in humans of a new TB vaccine is expected to begin by the end of the year, experts said yesterday in Washington at the Fourth World Congress on Tuberculosis. The planned safety trial would mark the first time in about 80 years that a new vaccine has been tested against the TB bacterium, which infects an estimated one-third of the world's population. In the past decade, there has been a resurgence of scientific effort and international funding to fight TB, which kills about 2 million people worldwide each year.

About 15 percent of funds from the Global Fund to Fight HIV, Tuberculosis and Malaria have been allocated to TB detection and treatment, said Kenneth Castro of the CDC. Bacterial strains that resist drug treatment are becoming increasingly prevalent, making the development of new drugs and vaccines essential to controlling the epidemic.

The TB vaccine is a new version of BCG, a partially effective vaccine introduced 80 years ago. BCG is widely used in developing countries to prevent severe TB in childhood. Developed by California researcher Marcus Horwitz, the new vaccine is genetically engineered to prompt production of a specific bacterial protein that has been found to protect mice from the disease, said Carol Nacy of the Sequella Foundation. The clinical trial is scheduled to take place in San Francisco.

Other vaccines being developed may be used to boost the immune system of TB-infected individuals to reduce their likelihood of developing active disease, or as an adjunct to drug treatment to prevent relapse, Nacy said. "We are not anywhere convinced that any of the vaccines [about to undergo] testing in humans today are going to be the vaccine," she said. "We simply have no way to know what is going to work."

Back to other CDC news for June 4, 2002

Previous Updates | Search the CDC archive