Summary:
The long standing wisdom that every form of bacteria is bad has led to the proliferation of sanitary practices that use chemicals more to provide a sense of control to humans (classified as war on germs, at least in the developed world) than for its long term effectiveness. With the increasing adoption of sanitation systems (including sewage systems, chlorinated water, food processing, refrigeration) has come a whole host of inflammatory diseases (skin and respiratory allergies) that have turned fatal across all age groups in the developed world. As the book calls it, skin and respiratory allergies are the 'Citizenship' disease that immigrants seem to suffer after they have acclimatized themselves in the developed world. People in developing and third world countries, who touch soil, drink unfiltered water and eat minimally processed and crudely stored food generally
have low incidence of inflammatory diseases. In addition, drug resistance has now developed for every known kind of disease causing bacteria. Antibiotics attack all the bacteria (harmful or not) in the human body. The widespread use of antibiotics in livestock feed in developed world has resulted in those antibiotics making their way into human bodies (through milk, eggs, meat). The book does not advocate going back to an era before antibiotics provided humans with a way to counter deadly epidemics. Rather, it focuses on using the power of antibiotics properly by learning about its interactions with bacteria in human body. In addition, the book suggests a host of approaches to handle outbreaks of bacterial diseases, some old (like being properly vaccinated) and some new (including genetic techniques, drug innovations).
Analysis:
Infectious diseases have been with humans for a very long time. Hunter gatherers lived in small pockets so infections did not have enough raw material (human bodies) to last long. In addition, the tribes did not interact with each other on a constant basis which would have enabled microbes to jump from one tribe to another. When humans walked out of Africa and developed settlements, the crowding and water contamination led to emergence of virulent microbes. The microbes that had lain quietly in human body for eons died with the hosts but the violent ones became successful (and lived longer) by jumping across hosts. Sumerians recorded the first recorded instance of infection. They
appeased gods to help them stave off death. In 16th century, Girolamo Fracastoro of Vienna came up with the scientific basis that became the germ theory of infectious diseases (it sounds like common sense now but in 16th century it was revolutionary):
1. Infectious disease always spreads through invisible contagious seeds
2. It does so by direct contact, contact with contaminated objects and through the air
3. Germs have distinct identities so one that causes fever is different from one that causes smallpox
4. Different disease (or germs) respond to different treatments
In late 17th century, Antonie Van Leeuwenhoek in Netherlands developed the first microscope to look at microbes. Hospitals opened in Europe for treating patients but lack of sterilization meant admission to hospital was deadlier than staying put at home. A doctor in England, Joseph Lister showed how sterile bandages and surgical instruments could improve survival rates of patients.With advances in understanding of germs, scientists in Europe split into 2 groups: Contagionists who stayed true to the original germ theory and hygienists who believed that the germs arose from filth and decay of European cities ('miasmas') and were transmitted through the air. Louis Pasteur showed through experiments that microbes are everywhere around us and that they do not arise from sterile matter spontaneously. This led to scientists on the contagion side gaining upper hand but hygienists played an important part in improving survival rates of patients by cleaning hospitals and preventing germs from infecting patients (Florence Nightingale was the most famous among them). From his studies of microbes, Pasteur put forward the theory that not all bacteria was harmful to humans and that some of them were quite beneficial. However, his student, Elie Metchnikoff argued that any bacteria was bad and his ideas have led to our present day approach of using antibiotics to obliterate all bacteria, whether harmful or not, from the human body. The next big advance came with the discovery of Penicillin by Alexander Fleming even though we would be talking about Ernest Duchesne of France if only he had survived. He was the first to come very close to discovering penicillin 20 years before Fleming but died of tuberculosis during his experimentation.
Some bacteria protect humans even before they are born. The book does an excellent job of taking the reader on a bacterial journey from before a baby is born, to its infancy. Lactobacilli (mother's vagina) and bifidobacteria (mother's breastmilk) protect newborns against a variety of harmful bacteria. When a baby is delivered vaginally, it is exposed to bacteria from her mother's body that are present in her birth canal whereas a baby delivered through cesarean section misses out on the benefit of these microbes. When the baby comes out of the mother's womb, the modern day practice of cleaning up the baby quickly also removes beneficial bacteria that covers the baby's skin. With the
increased use of antibiotics, the beneficial bacteria get wiped out as well, allowing the harmful bacteria to thrive in infants. Harmful bacteria are always looking for chinks in the armor of a human body. Using antibiotics to kill off beneficial bacteria just makes the job of virulent bacteria that much easier. Scientists have observed that exposing a baby to antibiotics in its first year doubles the rate of allergies and asthma in later childhood years. Sanitary systems play a part too in the explosion of skin and respiratory allergies - scientists have shown that the children in highly sanitized countries have more of adult micro flora than children in developing and third world countries and consequently more allergies). A baby's mouth and nose have mechanisms that eject bacteria out of the body either through swallowing or coughing.
When the baby grows up, the risk of developing skin or respiratory allergies decreases with an increase in the number of children in the family. This led a British scientist, David Strachan to formulate the original hygiene hypothesis - The decrease in viral infections (measles, mumps, rubella, common cold etc.,.) suffered by modern day babies led to an increase in skin and respiratory allergies. However, after the initial observations, it could not be replicated. It was then modified into the present day hypothesis - Lack of early and continued exposure to microbes (around other children, animals, unsanitized water) appeared to promote auto immune disorders as children grew up. This has led to scientists coming up with vaccines that use bacteria from dirt (Mycobacterium Vaccae) to prod the immune system into action against harmful microbes. A variation of hygiene hypothesis put forth by Graham Rook,identifies 3 types of immune regulating organisms in human body - bacteria around us, bacteria within us and intestinal worms (it does not mean we have to let children suffer from intestinal worms as it causes stunted development, dysentery, anemia) inside us. The prevalence of drug resistant bacteria leads to more infections and scientists have found that more infections a person experiences, the greater the chances of arthritis,heart disease, stroke and cancer as it is the inflammation after the infection that lingers for a long time.
Antibiotics allowed doctors to save countless lives during deadly epidemics. Doctors also observed bacteria adapting to antibiotics very quickly. That led to pharmaceutical companies coming up with a whole class of antibiotics (clindamycin, fluoroquinolones, cephalosporin) that could wipe out any type of bacteria in the human body. Doctors started using these antibiotics as a matter of course as it allowed them to respond quickly to a patient instead of going through the painstaking step of identifying the specific bug killing the patient and using an antibiotic geared towards that bacteria. In addition, doctors also over prescribe antibiotics because they rely on tradition instead of evidence when it comes to determining the dosage amount. Even worse, some doctors prescribe antibiotics as a preventive measure against bacterial infections. With these antibiotics, in addition to the harmful bacteria, trillions of beneficial bacteria got wiped out as well. The ones who survive the antibiotics are the ones who developed resistance to these drugs.
Scientists showed that bacteria did not survive these antibiotics through adaptation but through pre- existing mutations. In response, doctors started administering multiple antibiotics in the hope of killing bacteria that survived the first dose but it only served to supercharge the evolution of disease resistant bacteria. The indiscriminate use of antibiotics has now led to the entire bacterial kingdom operating as a super organism by exchanging genes (this section of the book is absolutely fascinating), driven by the fundamental need for survival. After widespread news coverage of drug resistant bacterial epidemics (Clostridium Difficile in 2006), some doctors are now more aware
of the need to rein in antibiotics usage. However, the extensive use of antibiotics has now led to humans (at least in the developed world) becoming a reservoir of drug resistant bacteria. In addition to antibiotics, chemicals used in modern day antibacterial products like triclosan (used in antibacterial soaps, toothpastes, mouth washes, household cleaning products) have become fodder for the drug resistant bacteria. Hence, the desire of people in Western world to take their sanitary levels to ever extreme heights itself plays into the spread of drug resistant bacteria.
The other major source of antibiotic use is from livestock. In April 1950, Thomas Jukes and Robert Stokstad of Lederle Labs showed that adding 5 pounds of unpurified antibiotics to one tonne of animal feed would increase growth rate of piglets by 50%. This led to widespread use of antibiotics in what has now become "warehouse style" farming of animals. In the beginning, some Wisconsin cheesemakers did report that milk from their cows that had penicillin or aureomycin, was curdling more. However, those complaints were ignored. Furthermore, in their zeal for using antibiotics in animal feed, scientists claimed that antibiotics fed to an animal would do its job and then be broken down in the animal's stomach, never making its way to the dinner plate. That has been proven wrong time and again resulting in Salmonella and Campylobacter send 3 - 4 million Americans to hospital every year. The best evidence of downsides of using antibiotics in livestock feed comes from Europe. European Union banned usage of antibiotics in animal feed in 1999 and it has seen a sharp decline in the antibiotic exposure of Europeans. However, US and Canada continue to use antibiotics in their animal feed and the response of their livestock industry has been to turn the tables on scientists arguing that it is the microbes from humans that make their way into animals that then land back on humans dinner plate (in spite of scientists repeatedly disproving it).
The author provides some solutions for reducing antibiotics even though it is not at all clear whether they can be successful in practice - Doctors should eliminate unnecessary prescriptions, wean patients off antibiotics faster and use less disruptive and more targeted drugs wherever possible. She also goes through solutions that have already been tried and that worked in some cases but with some downsides (bacterial resistance) - using bacteriophages, plasmids, reducing antibiotics in livestock feed, drugs with on off switches). Some solutions that work without downsides (at least none that have been observed yet):
1. Vaccinations - Because vaccines use a dead version of bacteria themselves , it leverages human body's immune reaction
2. Probiotics - This allows development of intestinal microflora in human bodies but the difficulty is in distinguishing between scientifically sound ones and deceptively marketed commercial products
3. Drugs that bind to toxins in harmful bacteria - This immobilizes the harmful bacteria and allows the human body to replenish itself with normal intestinal microflora that can then be used to fight off the infection
Doctors nowadays are slowly moving away from heavy use of antibiotics and towards supporting patients by rapid infusion of replacement fluids, better vessel constricting drugs and maintaining optimum blood glucose levels when fighting off an infection. Dietary changes like increasing dietary fats (olive oil, fish oils) can help protect from inflammations and ease the pain from chronic inflammatory disorders. In the long term, humans should acknowledge bacteria outnumbers them in this world by quite a margin and attempts to protect ourselves by sterilizing surfaces and objects (door knobs, skin) is a fool's errand. I am reminded of an episode of Monk when trash piles up in San Francisco and to alleviate his obvious distress, his boss takes him to an ultra clean environment (chip manufacturing facility) to show him what a place devoid of germs looks and smells like. The constant drumbeat of fears about a terrorist attack using biological weapons has also played its part in people hiding behind an array of germ fighting techniques that target bacteria with a hammer and not a scalpel.
Other Books for Reference:
Chasing Dirt: The American Pursuit of Cleanliness - Suellen Hoy
The Antibiotic Paradox - Stuart Levy
The long standing wisdom that every form of bacteria is bad has led to the proliferation of sanitary practices that use chemicals more to provide a sense of control to humans (classified as war on germs, at least in the developed world) than for its long term effectiveness. With the increasing adoption of sanitation systems (including sewage systems, chlorinated water, food processing, refrigeration) has come a whole host of inflammatory diseases (skin and respiratory allergies) that have turned fatal across all age groups in the developed world. As the book calls it, skin and respiratory allergies are the 'Citizenship' disease that immigrants seem to suffer after they have acclimatized themselves in the developed world. People in developing and third world countries, who touch soil, drink unfiltered water and eat minimally processed and crudely stored food generally
have low incidence of inflammatory diseases. In addition, drug resistance has now developed for every known kind of disease causing bacteria. Antibiotics attack all the bacteria (harmful or not) in the human body. The widespread use of antibiotics in livestock feed in developed world has resulted in those antibiotics making their way into human bodies (through milk, eggs, meat). The book does not advocate going back to an era before antibiotics provided humans with a way to counter deadly epidemics. Rather, it focuses on using the power of antibiotics properly by learning about its interactions with bacteria in human body. In addition, the book suggests a host of approaches to handle outbreaks of bacterial diseases, some old (like being properly vaccinated) and some new (including genetic techniques, drug innovations).
Analysis:
Infectious diseases have been with humans for a very long time. Hunter gatherers lived in small pockets so infections did not have enough raw material (human bodies) to last long. In addition, the tribes did not interact with each other on a constant basis which would have enabled microbes to jump from one tribe to another. When humans walked out of Africa and developed settlements, the crowding and water contamination led to emergence of virulent microbes. The microbes that had lain quietly in human body for eons died with the hosts but the violent ones became successful (and lived longer) by jumping across hosts. Sumerians recorded the first recorded instance of infection. They
appeased gods to help them stave off death. In 16th century, Girolamo Fracastoro of Vienna came up with the scientific basis that became the germ theory of infectious diseases (it sounds like common sense now but in 16th century it was revolutionary):
1. Infectious disease always spreads through invisible contagious seeds
2. It does so by direct contact, contact with contaminated objects and through the air
3. Germs have distinct identities so one that causes fever is different from one that causes smallpox
4. Different disease (or germs) respond to different treatments
In late 17th century, Antonie Van Leeuwenhoek in Netherlands developed the first microscope to look at microbes. Hospitals opened in Europe for treating patients but lack of sterilization meant admission to hospital was deadlier than staying put at home. A doctor in England, Joseph Lister showed how sterile bandages and surgical instruments could improve survival rates of patients.With advances in understanding of germs, scientists in Europe split into 2 groups: Contagionists who stayed true to the original germ theory and hygienists who believed that the germs arose from filth and decay of European cities ('miasmas') and were transmitted through the air. Louis Pasteur showed through experiments that microbes are everywhere around us and that they do not arise from sterile matter spontaneously. This led to scientists on the contagion side gaining upper hand but hygienists played an important part in improving survival rates of patients by cleaning hospitals and preventing germs from infecting patients (Florence Nightingale was the most famous among them). From his studies of microbes, Pasteur put forward the theory that not all bacteria was harmful to humans and that some of them were quite beneficial. However, his student, Elie Metchnikoff argued that any bacteria was bad and his ideas have led to our present day approach of using antibiotics to obliterate all bacteria, whether harmful or not, from the human body. The next big advance came with the discovery of Penicillin by Alexander Fleming even though we would be talking about Ernest Duchesne of France if only he had survived. He was the first to come very close to discovering penicillin 20 years before Fleming but died of tuberculosis during his experimentation.
Some bacteria protect humans even before they are born. The book does an excellent job of taking the reader on a bacterial journey from before a baby is born, to its infancy. Lactobacilli (mother's vagina) and bifidobacteria (mother's breastmilk) protect newborns against a variety of harmful bacteria. When a baby is delivered vaginally, it is exposed to bacteria from her mother's body that are present in her birth canal whereas a baby delivered through cesarean section misses out on the benefit of these microbes. When the baby comes out of the mother's womb, the modern day practice of cleaning up the baby quickly also removes beneficial bacteria that covers the baby's skin. With the
increased use of antibiotics, the beneficial bacteria get wiped out as well, allowing the harmful bacteria to thrive in infants. Harmful bacteria are always looking for chinks in the armor of a human body. Using antibiotics to kill off beneficial bacteria just makes the job of virulent bacteria that much easier. Scientists have observed that exposing a baby to antibiotics in its first year doubles the rate of allergies and asthma in later childhood years. Sanitary systems play a part too in the explosion of skin and respiratory allergies - scientists have shown that the children in highly sanitized countries have more of adult micro flora than children in developing and third world countries and consequently more allergies). A baby's mouth and nose have mechanisms that eject bacteria out of the body either through swallowing or coughing.
When the baby grows up, the risk of developing skin or respiratory allergies decreases with an increase in the number of children in the family. This led a British scientist, David Strachan to formulate the original hygiene hypothesis - The decrease in viral infections (measles, mumps, rubella, common cold etc.,.) suffered by modern day babies led to an increase in skin and respiratory allergies. However, after the initial observations, it could not be replicated. It was then modified into the present day hypothesis - Lack of early and continued exposure to microbes (around other children, animals, unsanitized water) appeared to promote auto immune disorders as children grew up. This has led to scientists coming up with vaccines that use bacteria from dirt (Mycobacterium Vaccae) to prod the immune system into action against harmful microbes. A variation of hygiene hypothesis put forth by Graham Rook,identifies 3 types of immune regulating organisms in human body - bacteria around us, bacteria within us and intestinal worms (it does not mean we have to let children suffer from intestinal worms as it causes stunted development, dysentery, anemia) inside us. The prevalence of drug resistant bacteria leads to more infections and scientists have found that more infections a person experiences, the greater the chances of arthritis,heart disease, stroke and cancer as it is the inflammation after the infection that lingers for a long time.
Antibiotics allowed doctors to save countless lives during deadly epidemics. Doctors also observed bacteria adapting to antibiotics very quickly. That led to pharmaceutical companies coming up with a whole class of antibiotics (clindamycin, fluoroquinolones, cephalosporin) that could wipe out any type of bacteria in the human body. Doctors started using these antibiotics as a matter of course as it allowed them to respond quickly to a patient instead of going through the painstaking step of identifying the specific bug killing the patient and using an antibiotic geared towards that bacteria. In addition, doctors also over prescribe antibiotics because they rely on tradition instead of evidence when it comes to determining the dosage amount. Even worse, some doctors prescribe antibiotics as a preventive measure against bacterial infections. With these antibiotics, in addition to the harmful bacteria, trillions of beneficial bacteria got wiped out as well. The ones who survive the antibiotics are the ones who developed resistance to these drugs.
Scientists showed that bacteria did not survive these antibiotics through adaptation but through pre- existing mutations. In response, doctors started administering multiple antibiotics in the hope of killing bacteria that survived the first dose but it only served to supercharge the evolution of disease resistant bacteria. The indiscriminate use of antibiotics has now led to the entire bacterial kingdom operating as a super organism by exchanging genes (this section of the book is absolutely fascinating), driven by the fundamental need for survival. After widespread news coverage of drug resistant bacterial epidemics (Clostridium Difficile in 2006), some doctors are now more aware
of the need to rein in antibiotics usage. However, the extensive use of antibiotics has now led to humans (at least in the developed world) becoming a reservoir of drug resistant bacteria. In addition to antibiotics, chemicals used in modern day antibacterial products like triclosan (used in antibacterial soaps, toothpastes, mouth washes, household cleaning products) have become fodder for the drug resistant bacteria. Hence, the desire of people in Western world to take their sanitary levels to ever extreme heights itself plays into the spread of drug resistant bacteria.
The other major source of antibiotic use is from livestock. In April 1950, Thomas Jukes and Robert Stokstad of Lederle Labs showed that adding 5 pounds of unpurified antibiotics to one tonne of animal feed would increase growth rate of piglets by 50%. This led to widespread use of antibiotics in what has now become "warehouse style" farming of animals. In the beginning, some Wisconsin cheesemakers did report that milk from their cows that had penicillin or aureomycin, was curdling more. However, those complaints were ignored. Furthermore, in their zeal for using antibiotics in animal feed, scientists claimed that antibiotics fed to an animal would do its job and then be broken down in the animal's stomach, never making its way to the dinner plate. That has been proven wrong time and again resulting in Salmonella and Campylobacter send 3 - 4 million Americans to hospital every year. The best evidence of downsides of using antibiotics in livestock feed comes from Europe. European Union banned usage of antibiotics in animal feed in 1999 and it has seen a sharp decline in the antibiotic exposure of Europeans. However, US and Canada continue to use antibiotics in their animal feed and the response of their livestock industry has been to turn the tables on scientists arguing that it is the microbes from humans that make their way into animals that then land back on humans dinner plate (in spite of scientists repeatedly disproving it).
The author provides some solutions for reducing antibiotics even though it is not at all clear whether they can be successful in practice - Doctors should eliminate unnecessary prescriptions, wean patients off antibiotics faster and use less disruptive and more targeted drugs wherever possible. She also goes through solutions that have already been tried and that worked in some cases but with some downsides (bacterial resistance) - using bacteriophages, plasmids, reducing antibiotics in livestock feed, drugs with on off switches). Some solutions that work without downsides (at least none that have been observed yet):
1. Vaccinations - Because vaccines use a dead version of bacteria themselves , it leverages human body's immune reaction
2. Probiotics - This allows development of intestinal microflora in human bodies but the difficulty is in distinguishing between scientifically sound ones and deceptively marketed commercial products
3. Drugs that bind to toxins in harmful bacteria - This immobilizes the harmful bacteria and allows the human body to replenish itself with normal intestinal microflora that can then be used to fight off the infection
Doctors nowadays are slowly moving away from heavy use of antibiotics and towards supporting patients by rapid infusion of replacement fluids, better vessel constricting drugs and maintaining optimum blood glucose levels when fighting off an infection. Dietary changes like increasing dietary fats (olive oil, fish oils) can help protect from inflammations and ease the pain from chronic inflammatory disorders. In the long term, humans should acknowledge bacteria outnumbers them in this world by quite a margin and attempts to protect ourselves by sterilizing surfaces and objects (door knobs, skin) is a fool's errand. I am reminded of an episode of Monk when trash piles up in San Francisco and to alleviate his obvious distress, his boss takes him to an ultra clean environment (chip manufacturing facility) to show him what a place devoid of germs looks and smells like. The constant drumbeat of fears about a terrorist attack using biological weapons has also played its part in people hiding behind an array of germ fighting techniques that target bacteria with a hammer and not a scalpel.
Other Books for Reference:
Chasing Dirt: The American Pursuit of Cleanliness - Suellen Hoy
The Antibiotic Paradox - Stuart Levy
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