TB vaccine and Diabetes

The Tuberculosis (TB) BCG vaccine is normally given to children under 5 years of age, and is often given at birth in the developing world, especially where TB is common. In Australia, we usually only give this vaccine to small children who will be visiting countries where TB is common.

TB vaccine and Diabetes

Recent research by Dr. Faustman and her lab have found that the TB vaccine assists in the treatment of Diabetes. This is really weird and a bit exciting. A small group of persons with longstanding diabetes were given two TB vaccines about 4 weeks apart and found after 3 years, that their sugar control was better. ( They still took all their normal insulin and had all their regular treatment; we can’t throw away the insulin quite yet.)  The effect was small but was definitely statistically significant.

This news about TB vaccine and Diabetes from the Faustman lab is certainly attracting media attention.  Here is an article in the Times,  and the WashingtonPost 

This article reports Dr. Faustman discussing the mechanism for why she thinks it works/ how the TB vaccine affects Diabetes. Dr. Faustmans book, “The Value of BCG and TNF in Autoimmunity” is available here.

The story of a really old vaccine helping to ease Diabetes may sound very weird, but the research is being done and published by reputable clinicians in the USA. The numbers are small and more research is needed before we change policy and start recommending TB vaccine for all diabetics, but it is tantalizing research that is worth understanding. The vaccine is generally very safe, so any benefit is rather appealing.

The vaccine for TB is a very old vaccine – first used in 1921.  It is usually given to newborns in high-risk countries, where it is very effective at preventing overwhelming and life-threatening tuberculosis.  It is a very safe vaccine for most people but does not work very well against TB in adults, so that is why it is usually not given after about 15 years of age. Persons born in the late 50’s early 60’s have likely had a BCG vaccine at school. As the rate of TB disease in the community fell, the authorities stopped giving vaccinations to the Australian population.  If you have had a TB vaccine, you will usually have a small round scar on the upper part of your left arm.

The TB vaccine is also a very unusual vaccine. I have previously written to describe reports that persons vaccinated against TB have a lower risk of the dangerous skin cancer, Melanoma.  There is also evidence that the TB vaccine may protect immunized babies from germs other than the tuberculosis germ. BCG is used in the treatment of some bladder cancers. It has also been found in some studies to give more protection against Leprosy then TB.

Old Friends?

The disease, Tuberculosis, has been infecting humans for over 70,000 years.

Have you heard of the “old friend’s hypothesis”?.  (It used to be called the hygiene hypothesis but the problem is not hygiene but the germs that were in the environment so it was re-named). Basically, the theory goes that…  Humans have evolved with their ( old friends ) bacteria over millennia,  to the point where if the ‘old friends’ bacteria are not present, the human body cannot properly calibrate its immune system, so it over-reacts to things – thus causing it to attack itself – meaning people develop auto-immune diseases such as multiple sclerosis.

Before all diabetics roll up their sleeves for a TB vaccine, I should point out that Diabetes Qld issued a cautionary statement reminding sufferers that this research is preliminary and the numbers are small.

The TB vaccine is a prescription product and a live vaccine, so there is always a small risk of side effects from the vaccine. There is not even an Australian registered TB vaccine – as the numbers who need it are very small in this country.

As with all of medicine, if you want to know more, speak to your diabetes doctor about this research and how it may relate to your individual circumstance.

Meantime, watch this space.

TB vaccine scar