A new, more effective vaccine to combat TB could soon be created
Although most of the world's population has been immunised against TB through the use of the BGC vaccine, it is estimated that at least 9 million new cases worldwide are reported each year, killing up to 4,700 people per day. This has sparked calls for a new vaccine to be created so that deaths caused by TB can be effectively prevented.
There is good news however as it seems that scientists are already on the way to developing a new vaccine. They are hoping this will be done using a protein that has been discovered which is secreted by the TB bacteria. TB, or tuberculosis, is caused by the bacterium Mycobacterium tuberculosis (MTB) which attacks the lungs. The bacterium is spread as an airborne infection and passes from person to person by coughing.
The current BCG vaccine is derived from Mycobacterium bovis bacterium which predominantly affects cattle and is also very similar to MTB. However, the new protein, called EspC, which has been discovered, is secreted only by the TB bacterium and not the BCG vaccine. Therefore the current vaccine does not provide an immune response to the protein. It is thought that once the new vaccine has been finalised then it can be used in conjunction with BCG vaccine to provide added immunity. EspC also provides a stronger immune respose so it could be more effective than the BCG vaccine.
It has also been suggested that the EspC protein could have other uses, such as aiding the early diagnosis of TB. The current skin prick test for TB, the Mantoux test, is unable to detect the difference between people who have been vaccinated with the BCG vaccine and those who are carrying the TB infection.
The findings were published in the Proceedings of the National Academy of Scienceswith the authors of the report speculating that the EspC protein could be the foundation for a new generation of both vaccination and diagnostic tool in combating TB.