Nothing Romantic About Tuberculosis (TB)

2009-03-25 | |
Last updated: 2009-03-25

When people think of tuberculosis or TB, they often think of a scourge that plagued mankind until the early 20th century when modern medicine finally conquered the disease. The reality of the situation is more about trying to stay one step ahead of a very resourceful and dangerous foe. Tuberculosis has been with humankind for at least the last 9000 years, but it was not until 1921 that the first vaccine called “BCG” was created to prevent infection and not until 1946 that the streptomycin antibiotic was available to cure the disease.

Despite the availability of a cure, one third of the world’s population is currently infected with this disease that will kill roughly 1.3 million this year or roughly 1.8 million when those who die of dual infection with HIV are also included. While most infected with TB will not develop the full-blown disease, 1 in 10 will and 50% of those who do will die. For a disease cured more than 60 years ago, there are still a considerable number of people dying. If we consider that the rate of new infections of the disease has only been decreasing since 2004, we can see that the fight against this disease has been very long, very difficult and is far from over.

While there exists a TB cure in the form of antibiotics, in the battle against TB, the primary means of fighting the disease has been through vaccination with more than 2 million infants inoculated per week around the world. However, over time the “BCG” vaccine has become less effective and in 1999 McGill University researchers were suggesting that that the bacteria used to create the vaccine had evolved so much that it had lost much of its similarity to TB, possibly making it completely ineffective. At the same time, drug and multi-drug resistant strains of TB are continuing to increase, effectively creating the potential for untreatable forms of the disease.

If we also consider the results of reports from both the European Union and Australia warning of the potential to lose significant ground in the battle against the disease, it is quite clear that considerable ongoing research effort is required to continue staying ahead of the disease.

To this end, a number of research efforts are underway that are crucial to maintaining the slight upper hand that we have against this disease.

One such effort has been the development of a means to deliver the vaccine in the same manner as the disease can spread; through the air. Researchers at the University of North Carolina at Chapel Hill and Harvard University have created a form of vaccine that can be delivered in aerosol form. When the aerosol was tested on animals exposed to both airborne TB and the vaccine aerosol at the same time, the rate of infection was between 5 and 10 times less than those animals that had received the “BCG” vaccine through injection. Were the results as favorable in human studies, the vaccine could be delivered through the use of inhalers at less cost and more easily than through injections.

Another avenue of research with considerable importance is the development of new and faster tests. One such test being developed involves a bacteria-attacking virus that has been genetically altered to glow green. When placed in the presence of drug resistant TB, the virus causes the TB bacteria to glow green and thus allows a clinic to quickly determine that the patient will need more aggressive drug therapy. Should this testing be successful, many more lives could be saved with more timely and appropriate treatment.

A final important area of research is the creation of new TB vaccine to replace the waning “BCG” variety. In this case, the announcement by McMaster University regarding the start of clinical trials is very important news. Given the importance of vaccine in the battle against the disease, this research alone suggests some promise in staying one step ahead.

While HIV may be the top scourge in terms of deadly infectious disease, TB has plenty of blood on its hands and must continually be fought. Despite humankind having had a cure for the disease for more than 60 years, the disease continues to kill and it will only be through relentless research that we may someday eradicate the disease and be able to forget about March 24th as World TB day.

Related Links:

Tags: , , , ,

Category: Uncategorized

Comments are closed.