Safety and Health Topics: Tuberculosis

According to the Centers for Disease Control and Prevention (CDC), nearly one-third of the world's population is infected with Tuberculosis (TB), which kills almost 2 million people per year. TB causes more deaths than any other infectious agent in the world. In the mid-1980s, a resurgence of outbreaks in the United States brought renewed attention to TB. An increase in high risk, immuno-suppressed individuals, particularly those infected with HIV, lead to an increase in TB cases. Drug-resistant strains of this deadly disease also contributed to the problem. However, through a broad range of Federal and community initiatives, TB rates have declined steadily over the past decade.

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Guarding Against Tuberculosis Safety Training Videos

Tuberculosis (TB)

Beating the World’s Most Successful Bug

Vaccines being developed by Dr. Jacobs and his colleagues are more severely weakened than the strain of TB in BCG and are weakened through the deliberate and specific deletions of critical M. tb genes.  The bacterium infects one-third of the world’s population and can survive for decades inside immune system cells, called macrophages, that kill many other disease-causing organisms. But Dr. Jacobs, of Albert Einstein College of Medicine in New York City, says a detailed understanding of M. tb ’s genetics is emerging from work in his and other labs and may lead researchers to new and more effective ways to prevent TB.

Tuberculosis researcher William R. Jacobs, Jr., Ph.D., calls his foe, Mycobacterium tuberculosis (M. tb ), the planet’s most successful pathogen.  Dr. Jacobs has devised ways to find which genes M. tb must have to effectively invade and persist inside macrophages as well as the genes needed for robust growth inside the human host. Dr. Jacobs selectively mutates specific M. tb genes to create strains that cannot grow or persist well inside mouse models of TB. He and his colleagues are testing these mutants for their suitability as the basis of new kinds of TB vaccines.

Guidelines for the Investigation of Contacts of Persons with Infectious Tuberculosis

No safe exposure time to airborne M. tuberculosis has been established. If a single bacterium can initiate an infection leading to TB disease, then even the briefest exposure entails a theoretic risk. However, public health officials must focus their resources on finding exposed persons who are more likely to be infected or to become ill with TB disease. These guidelines establish a standard framework for assembling information and using the findings to inform decisions for contact investigations, but they do not diminish the value of experienced judgment that is required. As a practical matter, these guidelines also take into consideration the scope of resources (primarily personnel) that can be allocated for the work.