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Saturday, 8 November 2014

Antibiotics – Ignorant Musings

Q: How many people owe (or have owed) their lives to antibiotics?

A: Countless millions – perhaps billions.

We should really be asking about person/years. A person who was injected with penicillin in the 1940s may be dead now but may well have enjoyed many years of post-infection life. What is more, they may have borne/begotten offspring of which the same is true.

An example: Gordon was wounded in WWII. Gangrene set in. It was defeated with penicillin (plus 40 person/years or more). He had four children who were saved from death by penicillin or its successors (from pneumonia or whatever). If each one lived (on average) an additional 30 years (as a result of treatment with penicillin), we are already talking 160 p/y. Perhaps some of them might have fought off the infection on their own. But then some of them might have had offspring whose lives were likewise saved by teramycin or its successors.

My enchanting granddaughter, Clara, is the product of 2 parents, 4 grandparents and 8 great grandparents, every one of which might have been carried off by infection, but for antibiotics, in the more than half-century since Alexander Fleming’s great discovery. The very thought leaves me tremulous. [Lord, Jesus Christ, make Your face to shine upon AF.] Multiply precious Clara by the many millions of babies born this year. The number is staggering!

Antibiotics have served us very well. But there are problems. There are now populations of disease causing bacteria which cannot be destroyed with antibiotics: C-Dif and MRSA, for example. Ebola is a different case – viruses cannot be killed with antibiotics.

It may be that doctors prescribe antibiotics too readily. It may be that patients do not use their medications as responsibly as they should.

Whatever, the orthodox (Darwinian) explanation is that bacteria mutate (viruses too, allegedly). I have a problem with this and I know I am not on a secure footing here. Please keep peppered moths in mind here – and bear with me. I will read your comments respectfully.

Is fortuitous mutation the explanation? How do bacteria know how to produce antibiotic resistant offspring? Pace Rupert Sheldrake, who may have a better explanation, I hazard the following. Let us reverse the scenario. Let us think of a human population invaded by a disease (instead of a bacterial population attacked by an antibiotic), the plague, for example. When it struck, some people, with natural immunity, survived – and so did their offspring. Europe was not wiped out by the plague. Europe survived.

A population of bacteria is stricken by antibiotic chemicals; some individual bugs, with natural immunity, survive.

Scenario 1) There are not enough survivors to kill the patient. Her own immune system sees them off.

Scenario 2) The survivors are numerous and potent enough to make the patient sick and/or infectious. She may survive but if she infects another person, he is now hosting a population of resistant bugs. No mutation is required but his doctors cannot treat him with the same antibiotic chemical because only resistant bugs were passed on to him.

Digression: Peppered Moths. One of the arguments in the Origin [sic] of Species featured peppered moths. Entomologists had observed that with the advent of industrial pollution, which darkened the trunks of trees, only dark coloured moths were to be found, whereas earlier the observed moths of this species had been light coloured. Darwin surmised (he was a clever bloke) that Natural Selection had turned light coloured moths into dark coloured moths. The trouble is: there had always been both light and dark moths. Pollution favoured the dark coloured ones – they were camouflaged against dark trunks and predatory birds couldn’t see them. With decreased pollution, following Clean Air legislation, the light coloured moths predominated because now they were the ones with camouflage – a perfect case of micro-evolution. Jonathan Wells cites Peppered Moths in his Icons of Evolution.

What about the future? Will the clever microbiologists at Big Pharma continue to stay ahead of the bugs? Or will the next breakthrough involve beefing up our immune systems? Are the clever microbiologists on the case already? I hope so. I am already worrying about Clara’s offspring.

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