10% Human: How Your Body’s Microbes Hold the Key to Health and Happiness. Alanna Collen

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СКАЧАТЬ had no clear idea of the form that death was taking on its passage from the morgue to the maternity ward, but he had an idea of how to stop it. To rid themselves of the stench of rotting flesh, doctors often washed with a solution of chlorinated lime. Semmelweis reasoned that if it could remove the smell, perhaps it could remove the vector of death as well. He instituted a policy that doctors must wash their hands in chlorinated lime between conducting autopsies and examining their patients. Within a month, the death rate in his clinic had dropped to match that of the midwives’ clinic.

      Despite the dramatic results Semmelweis achieved in Vienna and later in two hospitals in Hungary, he was ridiculed and ignored by his contemporaries. The stiffness and stench of a surgeon’s scrubs were said to be a mark of his experience and expertise. ‘Doctors are gentlemen, and gentlemen’s hands are clean,’ said one leading obstetrician at the time, all the while infecting and killing dozens of women each month. The mere notion that doctors could be responsible for bringing death, not life, to their patients caused huge offence, and Semmelweis was cast out of the establishment. Women continued to risk their lives giving birth for decades, as they paid the price of the doctors’ arrogance.

      Twenty years later, the great Frenchman Louis Pasteur developed the germ theory of disease, which attributed infection and illness to microbes, not miasma. In 1884, Pasteur’s theory was proved by the elegant experiments of the German Nobel prize-winning doctor Robert Koch. By this time, Semmelweis was long dead. He had become obsessed by childbed fever, and had gone mad with rage and desperation. He railed against the establishment, pushing his theories and accusing his contemporaries of being irresponsible murderers. He was lured by a colleague to an insane asylum, under the pretence of a visit, then forced to drink castor oil and beaten by the guards. Two weeks later, he died of a fever, probably from his infected wounds.

      Nonetheless, germ theory was the breakthrough that gave Semmelweis’s observations and policies a truly scientific explanation. Steadily, antiseptic hand-washing was adopted by surgeons across Europe. Hygienic practices became common after the work of the British surgeon Joseph Lister. In the 1860s, Lister read of Pasteur’s work on microbes and food, and decided to experiment with chemical solutions on wounds to reduce the risk of gangrene and septicaemia. He used carbolic acid, which was known to stop wood from rotting, to wash his instruments, soak dressings and even to clean wounds during surgery. Just as Semmelweis had achieved a drop in the death rate, so too did Lister. Where 45 per cent of those he operated on had died before, Lister’s pioneering use of carbolic acid slashed mortality by two-thirds, to around 15 per cent.

      Closely following Semmelweis’s and Lister’s work on hygienic medical practice was a third public health innovation – a development that prevented millions from becoming ill in the first place. As in many developing countries today, water-borne diseases were a major health hazard in the West before the twentieth century. The sinister forces of miasma were still at work, polluting rivers, wells and pumps. In August 1854, the residents of London’s Soho district began to fall ill. They developed diarrhoea, but not as you or I might know it. This was white, watery stuff, and there was no end of it. Each person could produce up to 20 litres per day, all of which was dumped in the cesspits beneath Soho’s cramped houses. The disease was cholera, and it killed people in their hundreds.

      Dr John Snow, a British doctor, was sceptical of the miasma theory, and had spent some years looking for an alternative explanation. From previous epidemics, he had begun to suspect that cholera was water-borne. The latest outbreak in Soho gave him the opportunity to test his theory. He interviewed Soho residents and mapped cholera cases and deaths, looking for a common source. Snow realised that the victims had all drunk from the same water pump on Broad Street (now Broadwick Street) at the heart of the outbreak. Even deaths further afield could be traced back to the Broad Street pump, as cholera was carried and passed on by those infected there. There was one anomaly: a group of monks in a Soho monastery who got their water from the same pump were completely unaffected. It was not their faith that had afforded them protection, though, but their habit of drinking the pump’s water only after they had turned it into beer.

      Snow had looked for patterns – connections between those who had become ill, reasons why others had escaped, links explaining the appearance of the disease outside its Broad Street epicentre. His rational study used logic and evidence to unravel the outbreak and trace its source, eliminating red herrings and accounting for anomalies. His work led to the disabling of the Broad Street pump and the subsequent discovery that a nearby cesspit had overflowed and was contaminating the water supply. It was the first-ever epidemiological study – that is, it used the distribution and patterns of a disease to understand its source. John Snow went on to use chlorine to disinfect the water supplying the Broad Street pump, and his chlorination methods were quickly put to use elsewhere. As the nineteenth century came to a close, water sanitation had become widespread.

      As the twentieth century unfolded, all three public health innovations became more and more sophisticated. By the end of the Second World War, a further five diseases could be prevented through vaccination, taking the total to ten. Medical hygiene techniques were adopted internationally, and chlorination became a standard process in water-treatment plants. The fourth and final innovation to put an end to the reign of microbes in the developed world began with one world war and concluded with the second. It was the result of the hard work, and good fortune, of a handful of men. The first of these, the Scottish biologist Sir Alexander Fleming, is famously credited with ‘accidentally’ discovering penicillin in his laboratory at St Mary’s Hospital in London. In fact, Fleming had been hunting for antibacterial compounds for years.

      During the First World War he had treated wounded soldiers on the Western Front in France, only to see many of them die from sepsis. When the war came to an end and Fleming returned to the UK, he made it his mission to improve upon Lister’s antiseptic carbolic acid dressings. He soon discovered a natural antiseptic in nasal mucus, which he called lysozyme. But, as with carbolic acid, it could not penetrate beneath the surface of wounds, so deep infections festered. Some years later, in 1928, Fleming was investigating staphylococci bacteria – responsible for boils and sore throats – when he noticed something odd on one of his Petri dishes. He had been on holiday, and had returned to a messy lab bench full of old bacterial cultures, many of which had been contaminated with moulds. As he sorted through them, he noticed one dish in particular. Surrounding a patch of Penicillium mould was a clear ring, completely free of the staphylococci colonies that covered the remainder of the plate. Fleming spotted its significance: the mould had released a ‘juice’ that had killed the bacteria around it. That juice was penicillin.

      Though growing the Penicillium had been unintentional, Fleming’s recognition of its potential importance was anything but accidental. It began a process of experimentation and discovery that would span two continents and twenty years, and revolutionise medicine. In 1939, a team of scientists at Oxford University, led by the Australian pharmacologist Howard Florey, thought they could make more use of penicillin. Fleming had struggled to grow significant quantities of the mould, or to extract the penicillin it produced. Florey’s team managed it, isolating small amounts of liquid antibiotic. By 1944, with the financial support of the War Production Board in the United States, penicillin was produced in sufficient quantities to meet the needs of soldiers returning from the D-Day invasion of Europe. Sir Alexander Fleming’s dream of beating the infections of the war wounded was realised, and the following year he, Florey, and one other member of the Oxford team, Sir Ernst Boris Chain, received the Nobel Prize in Medicine or Physiology.

      Over twenty varieties of antibiotics have subsequently been developed, each attacking a different bacterial weakness, and providing our immune systems with backup when they are overwhelmed by infection. Before 1944, even scratches and grazes could mean a frighteningly high chance of death by infection. In 1940, a British policeman in Oxfordshire called Albert Alexander was scratched by a rose thorn. His face became so badly infected that he had to have his eye removed, and he was on the verge of death. Howard Florey’s wife Ethel, who was a doctor, persuaded Florey that Constable Alexander should become the first recipient of penicillin.

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