Tuberculosis (TB) is a serious, debilitating and highly contagious disease affecting millions of people worldwide. If not properly treated, it is often fatal.
Spread through the air from one person to another when an infected person coughs or sneezes, the bacteria that cause TB usually attack the lungs. However, TB can attack other parts of the body, including the kidneys, the spine and the brain.
Until the mid-20th century a leading cause of death in the developed world, TB remains a scourge in many developing countries. And new drug-resistant strains have caused its reemergence as a health threat even in regions where until recently medical treatment had kept the disease at bay.
As a result, the TB pandemic continues unabated. Despite efforts to control and treat tuberculosis, every year eight million more people are infected with the disease, and upwards of 1.7 million people — many of them children — die.
Mycobacterium tuberculosis (M.tb), the bacterium that causes tuberculosis, is present in one-third of the world's population, though not everyone shows signs of the disease. Mounting drug resistance, including multi- and extensively drug resistant TB (MDR-TB and XDR-TB), coupled with the growing number of people co-infected with TB and HIV, make the pandemic more threatening and more deadly.
Why a New Vaccine
To win the fight against TB, a comprehensive approach is needed that includes new and more effective vaccines as well as improved diagnostics and treatment.
The Bacille Calmette-Guérin (BCG) vaccine, created in 1921, is the only existing vaccine against TB. Unfortunately, it is only partially effective. It provides some protection against severe forms of pediatric TB, but is unreliable against adult pulmonary TB, which accounts for most of the disease burden worldwide. Although BCG is the most widely administered vaccine in the world, there have never been as many cases of TB on the planet. There is therefore an urgent need for a modern, safe and effective vaccine that would prevent all forms of TB, including the drug-resistant strains, in all age groups and among people with HIV.
Current Challenges
Treating TB is challenging, even in developed countries where there is a modern health care system and infrastructure. Current treatment regimens last six to nine months, and erratic or inconsistent treatment breeds multidrug-resistant and even extensively drug-resistant TB, which means that this pandemic could become even more difficult to control throughout the world.
TB is a leading cause of death among people who are also infected with HIV, according to the World Health Organization. One-third of the 33.2 million people living with HIV also suffer from TB. Without proper treatment, approximately 90 percent of people living with HIV die within two to three months of contracting TB.
The Current Situation
Someone in the world is infected with tuberculosis every second.
Two billion people worldwide are infected with TB — about one out of every three people on the planet.
TB kills nearly 1.8 million people a year.
Among people who are also infected with HIV, TB is a leading cause of death.
Multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of TB are found throughout the world.
Despite being one of the most widely used vaccines in the world today, the TB vaccine — BCG — has had no apparent impact on the TB pandemic.