It's a big story (and getting bigger every day), so it won't be knocked over quickly. I anticipate that it may take several weeks to tell, in several parts. I plan for it to be a thread of blog entries that runs in the background, liberally interspersed with blog entries on other matters, as they arise.
As always, I welcome your comments - particularly if I have made any mistakes or have missed or glossed over something that is relevant.
Tuberculosis (TB).
Cellestis' current main product line is a method for diagnosing Tuberculosis. This diagnostic method does have many other current and potential applications. I will get to those but for the moment I will concentrate on TB as it is the "company maker".
What is TB?
TB is an infection by the bacterium Mycobacterium tuberculosis. Whilst this bacterium is most commonly known as an an infection of the lungs, it can and does infect practically any part of the body. If not successfully treated, TB can result in death.
Some facts about TB.
If you are anything like I was before I started learning about TB, you may have thought "But wasn't TB eradicated back in the 1960's?". Nothing could be further from the truth. Check out these facts.
- - Around 2 million people die from the TB disease each year;
- - It is estimated that there are around 10 million new cases of TB each year;
- - TB is found in every country in the world;
- - TB is the leading killer of people with HIV/AIDS;
- - An undiagnosed person with active TB spreads the disease to 10 to 15 other people in a year;
- - It is thought that around 30% of people in the world are currently infected with TB (the majority in the underdeveloped world) and that a person infected with TB has a 10% lifetime risk of developing full blown (active) TB. *
* I will be commenting on this statistic later
As you delve further into the TB story you will find many references to these two "forms" of TB (more correctly - "states" of TB). Particularly as it relates to Cellestis, it is a concept that needs to be understood. (and you are still thinking about your own 30% chance of being infected).
The TB bacterium is an insidious little bug. Fortunately, under normal circumstance, the body has a most amazing (I really mean amazing - I am fascinated by it every day) immune system for dealing with all sorts of infections - including TB. There is a constant war going on our body. If we have a competent immune system then we are able to attack and destroy most infections that attack us daily. However, TB is particularly tricky, when it is attacked by the immune system, it retreats and goes into a dormant state. I like to visualize this as it building a protective shell over itself while the immune system waits outside to keep it contained. A sort of "standoff". This "dormant" state is termed latent TB. In this state the TB causes you no harm. But, it is sitting there quietly waiting for conditions to be right for it to break out of it's shell and become full blown TB disease - active TB.
Latent TB is not transmissible. Only when TB becomes active can you "catch" TB from another person - essentially by breathing in the TB germs that somebody breathes, sneezes, coughs or spits into the air.
If for any reason the immune system becomes weakened then the latent TB can and will become active. Over a lifetime there are many factors that may cause the immune system to weaken - infection with other disease, certain treatments for other disease (TNF blockers commonly used for arthritis treatment are an example), old age, malnourishment etc etc. (I'm betting that a light bulb just went on flashing the realisation of why so many HIV sufferers die of TB).
Treatment of TB.
Both active and latent TB are treated (usually successfully) with various cocktails of antibiotics. However, unfortunately over time, the TB bacterium has evolved to be resistant to many of these antibiotics. The reason for this is primarily the non completion of treatment - allowing those bacterium with a natural resilience to the antibiotics to strengthen and flourish. This has resulted in a number of variants of TB to be circulating in the community. MDRTB (Multi Drug Resistant TB), XDRTB (Extensively Drug Resistant TB) and more recently the very nasty XXDRTB (Extremely Drug Resistant TB) which is virtually untreatable. All of the various incarnations of TB are equally transmissible. All of these variants of TB have been found throughout the world.
Bearing in mind that, statistically, a person with latent TB has a lifetime risk of 10% of a latent TB infection becoming active and then spreading to others, the only way that TB will ever be brought under control is to identify and treat that huge reservoir of latent TB sufferers. Incidentally, TB is much easier to treat at the latent stage than it is once it has become active.
Surely by now there must be a Vaccine?
Yes there is. The BCG vaccine has been available since 1921 and is the most widely used vaccine in the world. In simple terms it is a non virulent strain of TB derived from bovine TB that is injected into the body to "teach" the body how to fight TB if it should be encountered later. There is much ongoing research and discussion about the true effectiveness of this vaccine. It seems that it's best results are when it is administered to infants where it seems it might give between 10 and 15 years of protection. It's usefulness in adults is much less. Many countries have now ceased routine administration of the BCG vaccine.
Aside from the doubts about it's effectiveness, the BCG has one other major problem. This relates to the diagnosis of TB which we will come to next.
Diagnosis of TB.
This is where "the wheels hit the ground" with regard to the part that Cellestis is playing in the TB field.
Rather than rush this important topic, I will hold it over for the next chapter in this saga.
Read on ...
The Cellestis Story. Part Two.
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