The Miracle Cure That's Hiding In Plain Sight

You've maybe never heard of Bacillus Calmette–Guérin, but scratch a little deeper and you'll find that BCG, as it's commonly known, is one of the most overlooked wonder-drugs of our time.

BCG is first and foremost the world's most common tuberculosis vaccine, and was first used in humans all the way back in 1921. Made from a weakened strain of live bovine tuberculosis bacteria, it's been show to be up to 80 per cent effective in preventing TB for a duration of 15 years, depending on geographical location. That's pretty impressive, which is why - US aside - it's shoved into many a childhood arm around the world. But that's just the beginning.

Cancer killer

Jumping from TB to cancer is quite a leap, but it's one BCG has made time and again. As far back as 1979, a clinical trial declared that "BCG is beneficial in the treatment of lung cancer". Then, in 1991, a study published in the new England Journal of Medicine suggested that the BCG vaccine offered strong protection against the recurrence of bladder cancer.

There followed a 1994 trial which provided evidence that BCG increased survival time and reduced risk of recurrence in those suffering from malignant melanoma; reports that it was beneficial in the treatment of colorectal cancer; and, most recently, concrete examples of its beneficial effects in bladder cancer treatment.

TB, dead. Four disparate types of cancer kept in check. That alone would make for a pretty impressive scorecard.

But wait, there's more

But BCG has plenty more up its sleeve. Take multiple sclerosis, a disease in which the fatty sheaths around axons in the brain become damaged, in turn leading to scarring and, over time, cognitive disability. In 1999, it was demonstrated that BCG reduced the incidence of MS symptoms.

In a later study, it was shown that this effect was likely due to the fact the vaccineattenuated the scarring of nerve cells by up to 50 percent - an effect that was observed on MRI scans. While it's not commonly used as a treatment, it was deemed a safe and sensible use of the vaccine in the journal Neurology.

The list keeps going. A 2006 paper in the Lancet explained how BCG has a protective effect on leprosy, while another pointed out that it delayed the onset of Buruli ulcers - nasty growths beneath the surface of the skin. There are also a host of animal experiments which promise even more positive news: in particular, a mouse model of Parkinson's disease has shown that BCG provides a mild neuroprotective effect, and it's hoped it can be replicated in humans.

Not bad for a 90-year old treatment.

Old drug, new tricks

BCG's latest feat, though, is perhaps its most unexpected. Several years ago, Harvard professor Denise Faustman showed that BCG could be used to treat diabetes in mice.

She demonstrated that the vaccine helped mice to produce a protein which kills off T-cells, which are responsible for type 1 diabetes. With bated breath, the scientific community waited while the same experiments were replicated in humans. What was at stake? A positive finding could mean that diabetes patients no longer had to inject themselves with insulin.

Four years later, Fausmtan and her colleagues have published results from a very small-scale trial in PLoS One. Their work is limited and caveat-laden - the study looked at three patients for just 20 weeks - but the researchers observed the same protein production and T-cell death as they saw in mice. While it's not quite time for diabetes sufferers to pop the champagne corks and stop injecting insulin just yet, it's certainly a major finding that promises a great deal.

Perplexingly, we don't even really know quite what makes BCG so successful. There are hypotheses that suggest that it activates a protein called the "tumour necrosis factor-alpha" - and the diabetes study lends some weight to that idea - but the research community isn't 100 per cent sure yet. Put simply, though it seems to be helpful across many conditions, we don't yet know exactly why.

Ignore at your own risk

Given the success of BCG against so many disease, you might wonder why it's not more common. It's certainly not unsafe: it's one of the most widely used vaccines in the world, and has few adverse effects other than a little scarring where the injection is given. It's certainly not prohibitively expensive, either, as it's used throughout vast swathes of Asia and South America.

Perhaps more likely is that the US -- usually the pioneer in cutting-edge treatments -- has never really embraced BCG. Instead, it's always shunned the vaccine as a TB preventative, instead preferring to opt for programs of detection and treatment of latent tuberculosis. In turn, BCG is less commonplace in the US: medical professionals aren't as generally aware of it as in other parts of the world and, as a result, it sometimes goes overlooked.

Given what a panacea it's proven to be, though? Perhaps it's time that changed.

Image by Andres Rueda under Creative Commons license

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    80% MAXIMUM efficacy that is GEOLOGICALLY dependent is not impressive at all. Diphtheria, mumps, rubella, rotavirus all have much higher efficacies without geological changes.
    Where on earth did you get the idea that doctors don't know about BCG? Doctors are fully aware of its existence, except that it leaves a rather distinctive almost keloid-like scar, is not funded by the government in the UK or Australia, has little effectiveness in these countries, and has no efficacy when viewed from a public health perspective. The only people who really need BCG vaccines are those who work in refugee camps or in high risk areas or live in such areas for long periods of time, and even then the most the vaccine usually does is prevent further dissemination of bacteria from the infected person rather than preventing infection.

    Seriously, the conjecture on Gizmodo on "medicine" is just ridiculous.

      @ Matt. Yes, yes, GEOGRAPHICALLY. No, I don't know how to differentiate between granite and shale at a glance, but I doubt you know all the causes of clubbing of the fingers either, and I doubt you know rough granite and shale either anyway. Now instead of nitpicking, talk about the actual article.

    @Pili, so what you are saying is that the effectiveness of this vaccine is dependent upon what type of rock someone is standing on? How does standing on an igneous rock, versus a conglomerate rock affect the functionality of a vaccine? So, Diptheria, mumps, rubella, and rotavirus all work better if the recipient is made to stand on the same type of rock? Doctors should stick with being doctors, as they don't seem to know the difference between GEOLOGISTS and GEOGRAPHERS.

      Point taken. Still a poor observation though (my comment had legitimate points and yours had just one).

    I was more interested in the main body of the article which seemed very impressive, judging from the fact that people actually devoted time and money to researching it and obtained positive outcomes.

    I hope some doctors did read this, take issue and tell their friends about it because the more important "bigger issue" is that they do become aware of the alternate uses. Not all doctors devote their spare time to reading journals, many devote it to golf and overseas holidays. ;)

    "Given what a panacea it’s proven to be, though? Perhaps it’s time that changed."
    Ummm... none of the studies referenced in this article are proof of BCG's effectiveness outside it's primary use. At best, they indicate that it might be beneficial to look into it further. The fact that it has been around for so long, and not generally used in developed countries does indicate that other methods are at least as good.
    Once claims are substantiated (or not) the medical industry will respond appropriately.

    the BCG is given to every French and Canadian child at birth. Being permanent resident in Australia, we have been able to have it for my son for free (paid by Medicare). The only thing is that it has to be given before the 6th month of the child, after that, it is no longer effective. It does leave a scar, but you can chose to have it injected on the thigh or the bum instead of the arm.

      BCG is effective up to 5 years of age. It's interesting that your child received it though, as generally in Australia it's not available unless the person is to live in a high-risk area (since 2008).

    I thought this was going to be an article about weed.

    (Reading this post post..)

    Forgetting of course that nearly all health care workers in Australia have the BCG vaccine... (I have, and when I was training it was sort of mandatory.... My wife refuses to have it, as once it is administered the Mantoux test becomes totally ineffective for determining TB status... (though after several Mantoux tests, they start to test positive to the test itself.)

    SO it seems it is Used in Australia... for at-risk personnel only.

    Last edited 23/12/12 11:36 pm

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