The use of quarantineas a public health measure dates back to the 14th century when the Black Death ravaged Italy and the rest of Europe. Quarantine comes from the Italian ‘quarantena’, meaning forty-day period. Travelers and merchandise that had potentially been exposed to disease were isolated for a period of time to ensure that they weren't infected. Some cities and towns would create a "cordon sanitaire,' a physical barrier that could only be crossed with permission. This practice persisted into the late 19th century and early 20th century.
Systematic thinking about how to establish the determinants of health and disease was not suddenly invented by a single individual. It evolved over centuries. One can see sparks of insight intermittently over time. In the 1700s and 1800s one can see attempts to examine the causes of disease and the effectiveness of prevention and treatment in a systematic way.
Girolamo Fracastoro (1546): Girolamo Fracastoro (shown below) was an Italian physician, poet, astronomer, and geologist, who wrote about 'disease seeds' carried by wind or direct contact. In essence, he was proposing the germ theory of disease more than 300 years before its formal articulation by Louis Pasteur and Robert Koch.
In 1546, Fracastoro outlined his concept of epidemic diseases in "De contagione et contagiosis morbis" and speculated that each disease was caused by a different type of rapidly multiplying 'seed' and that these could be transmitted by direct contact, through the air, or on contaminated clothing and linens. Similar speculation had been mentioned as a possible cause of disease by the Roman scholar Marcus Varro in the 1st century BC.
It was once believed that life forms could arise spontaneously. Maggots, worms, & bacterial and fungal growth could be found "arising" from food that was left to stand. Francesco Redi was an Italian physician, naturalist, biologist and poet. He is referred to as the "founder of experimental biology", and as the "father of modern parasitology". He was the first person to challenge the theory of spontaneous generation by demonstrating that maggots come from eggs of flies. In 1699 Francesco Redi boiled broth and sealed it; no growth occurred, suggesting that Fracastoro was correct.
Beginning around 1592 the parish clerks in London began recording deaths. In 1662 John Graunt, a founding member of the Royal Society of London, summarized the data from these "Bills of Mortality" in a publication entitled "Natural and Political Observations Mentioned in a Following Index, and Made Upon the Bills of Mortality.” Graunt analyzed the data extensively and made a number of observations regarding common causes of death, higher death rates in men, seasonal variation in death rates, and the fact that some diseases had relatively constant death rates, while others varied considerably. Graunt also estimated population size and rates of population growth, and he was the first to construct a "life table" in order to address the issue of survival from the time of birth.
Anton van Leeuwenhouk (1670s): Van Leeuwenhouk's accomplishments were preceded by those of Robert Hooke, who had published "Micrographia" in 1665. Hooke devised a compound microscope and used it to examine and describe the structure of nature on a microscopic level, including insects, feathers, and plants. In fact, it was Hooke who discovered plant cells and coined the term "cells".
Anton van Leeuwenhoek of Holland was "the father of microscopy." He began as an apprentice in a dry goods store where magnifying glasses were used to inspect the quality of cloth. Van Leeuwenhoek was fascinated by the lenses and experimented with new methods for grinding and polishing more powerful lenses.
He was able to achieve magnifications up to 270x diameters. He used these to create the first useful microscopes. Using his inventions, he was the first to see bacteria (1674), yeast, protozoa, sperm cells, and red blood cells.
John Pringle and "Jail Fever" (1740s): John Pringle was a Scot who served as physician general to the British forces during the War of the Austrian Succession (1740–48). In London he became physician to the Duke of Cumberland and to King George III. Pringle published "Observations on the Diseases of the Army" in 1752, in which he proposed a number of measures aimed at improving the health of soldiers including improvements in hospital ventilation and camp sanitation, proper drainage, adequate latrines, and the avoidance of marshes.
He wrote expensively on the importance of hygiene to prevent typhus or "jail fever," which was a common malady among soldiers and prisoners in jails. Pringle incorrectly believed that typhus was caused by filth. In fact, it is caused by a small bacterium (a rickettsia). Lice are vectors for the disease; when infected lice defecate on the skin of lice-infested soldiers or prisoners, the bacteria can gain entry through small scratches or abrasions in the skin. The bacteria then multiply and cause a severe febrile illness which is often fatal if not treated. Pringle also coined the term 'influenza'.
Francois Broussais was a prominent Parisian physician and a strong proponent of bloodletting with leeches. He used bloodletting to treat many diseases, including cholera. It is believed that his vigorous use of bloodletting to treat victims of a cholera epidemic in Paris substantially contributed to the mortality rate.
Pierre Louis was a contemporary of Broussais's who believed in using numerical methods to evaluate treatment. Louis studied bloodletting and found it ineffective, but many dismissed his conclusions. Bloodletting was a therapy that had been practiced for centuries, although it had never been tested for efficacy. It had become embedded in medical practice.
In many respects, public health as we think of it today (i.e., as a function of good government) took shape in London and Paris in the wake of the devastating health consequences of the Industrial Revolution. However, the circumstances that propelled the development of public health as a discipline are more complex with many contributing factors. First, there was the notion of the importance of the monarchy and the power of the state. The influence and power of the state could be assessed in many ways including commerce and trade, but also by the size of the population and the health and fitness of the working population.
This crude notion made the work of John Graunt quite compelling, and the importance attached to "numbering the people" grew. Not surprisingly, the General Registrar's Office was established in 1837 to record compulsory registration of births, deaths, and marriages in England and Wales. Dr. William Farr (below) was appointed Chief Statistician; Farr had trained at the Royal Academy of Medicine in Paris. The General Registrar's Office established the importance of surveillance with respect to health.
A second factor was the emergence of the Enlightenment in the 18th century, which embraced democracy, citizenship, reason, rationality, and the social value of intelligence (the value of information gathering). These ideas provided important underpinnings for public health. In the early 1800s, Jeremy Bentham and his disciples (the theoretical radicals) developed the philosophy of utilitarianism which provided a theoretic underpinning for health policy and wider social policies. One theme was that the reduction of mortality and improvements in health had an economic value to society. Healthy workers were more able to contribute to the economy of the state. Implicit in utilitarianism was the notion that one could measure 'evil' by the degree of misery that was created (or relieved) by a particular action. To Bentham the welfare of both the wealthy and the poor could be achieved most efficiently with good government.
Yet another factor was the recognition that poor health was a burden that fell disproportionately on the poor.Villerme, a physician in Paris had noticed that mortality rates varied widely among the districts (arrondissement) of Paris. He tried to correlate mortality with the distance of the arrondissement from the Seine River, the relationship of the streets to the prevailing winds, the arrondissement's source of water and local climatological factors such as soil type, exposure to the sun, elevation and inclination of the arrondissement. None of these things correlated. However, when he used tax rates as an indicator of wealth, Villerme found a striking correlation with mortality rates.
In 1842 Sir Edwin Chadwick, a social reformer, published a report entitled the 'Report into the Sanitary Conditions of the Labouring Population of Great Britain' proving that life expectancy was much lower in towns than in the countryside.
Chadwick argued that it was possible for the government to improve people's lives through reform; he believed that a healthier population would be able to work harder and would cost less to support. He concluded that what was really needed was not more physicians, but civil engineers to provide drainage of streets and to devise more efficient ways of delivering clean water and removing sewage and other noxious substances. These social, economic, political, and philosophical developments all contributed to the emerging idea that the public's health was a legitimate interest of government.
It is interesting to note that many of the proponents of the "Sanitary Idea," including Edwin Chadwick (shown on the right), were "miasmatists" who clung to the belief that disease was caused by breathing foul vapors. Since sewage and garbage smelled bad, they were associated with disease, so the miasmatists pushed to clean up the environment. And despite the fact that their belief in miasmas would prove to be incorrect, the end result was that many of the sources of infectious disease were removed. Chadwick was instrumental in creating a central public health administration that paved the way for drainage, sewers, garbage disposal, regulation of housing, and regulations regarding nuisances and offensive trades. This "sanitary idea" resulted in remarkable improvements in health and well-being, as illustrated in the graph below, which shows a remarkable decline in mortality from tuberculosis from the mid-19th century until the mid-20th century.
Chadwick's report provided momentum for the establishment of a number of societies and pressure groups consisting of politicians, civil servants, & social reformers lobbied parliament. Among others, these included:
The Health of Towns Association, 1844
The Metropolitan Association for Improving the Dwellings of the Industrial Classes
The Association for Improving Cleanliness Among the Poor, and others.
Through their efforts landmark legislation was passed including:
1846 The Nuisances Removal Act was passed, giving local justices the power to prosecute and fine landlords for infractions having to do with sanitation (poor housing, garbage, cesspools and faulty drains).
1848 The Public Health Act created a General Board of Health in London that could direct localities to create local boards empowered to deal with environmental filth.
In the 1850s The Epidemiologic Society of London was formed, consisting of local physicians, ex-military commanders, and civil servants who presented papers related to public health issues.
1853: John Snow presented "The comparative mortality of large towns and rural districts and the causes by which it is influenced". This intersection of statistics, philosophy, and economy sparked a new agenda for social reform.
These efforts had an enormous impact. The graph below shows the remarkable decline in mortality from tuberculosis in the United Kingdom from 1850 to 1960. The remarkable decline in mortality from TB and other infectious diseases is believed to have been the result of the many environmental improvements that occurred as a result of the implementation of the "Sanitary Idea." Note the temporary up-surge in TB death rates during the World Wars I & II, when nutrition suffered and many were forced to live in cramped, poorly ventilated quarters.
Louis Pasteur (late 1800): Louis Pasteur was a French biologist and chemist who made enormous contributions to germ theory, to prevention of food spoilage, and to the control of disease. In 1853 Pasteur began studying fermentation in wine and beer and rapidly concluded that microorganisms were responsible. He also discovered that microbes in milk could be killed by heating to about 130 degrees Fahrenheit, a process which is now known as 'pasteurization'. He discovered that some microorganisms require oxygen (aerobic organisms), while others reproduce in the absence of oxygen (anaerobic).
Pasteur pioneered the idea of artificially generating weakened microorganisms as vaccines. Edward Jenner's work had demonstrated the principle with the naturally occurring cowpox, which could be used to vaccinate against smallpox. Pasteur was able to artificially weaken strains of anthrax and cholera in order to generate vaccines. It was, in fact, Pasteur who coined the term 'vaccine' in honor of Jenner's discovery. Pasteur developed vaccines against anthrax in sheep and cholera in chickens. In 1885 he developed a vaccine for rabies by growing it in rabbits and then drying the nerve tissue that had been infected with the virus. This vaccine was successfully used to save the life of a boy who had been bitten by a rabid dog.
Events in the US paralleled those in the United Kingdom. The US also underwent a rapid transition from a rural, agricultural society to one that was intensely urban and industrial. Inventions such as the cotton gin that promoted agricultural production, but also decreased the need for farm workers, driving many to the cities for work. Economic growth and inventions spawned factories and textile mills in US cities.
Resources :
1. Centers for Disease Control and Prevention History
2. Core Functions of Public Health
3. Public Health Museum in Massachusetts
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