ECJ EUROPEAN Cleaning Journal

In the second part of our special series looking back at the history of hygiene, ECJ asks how we first discovered germs and how harmful they can be. We look back at the pioneers who convinced us that bacteria can be so dangerous to public health and how their findings formed the very foundations of hygiene and public health as we know them today.

Prior to the discovery of microbial pathogens, many people believed that diseases resulted from evil spirits. Of course scientific breakthroughs during the 1800s proved that tiny microbes could cause fatal and deforming diseases such as tuberculosis and smallpox. And the most dramatic decreases in infectious diseases between the discovery of microbial contribution and the discovery of antibiotics came about because of changes in human behaviour – drinking clean water, hand washing and toilet flushing.

The principal architect of the sanitary reform movement in the 19th century was Sir Edwin Chadwick in the UK. He is associated with the increase in life expectancy from 17 years in factory workers in the north of England to today’s almost 80 years. Chadwick is credited with having a profound influence on the philosophy of hygiene and public health, and its translation into legislation. Believing that a healthier population would be able to work harder and cost less to support, he urged the improvement of drainage, housing and water supply.

In his Report on Sanitary Conditions of 1842 Chadwick stated: “The formation of all habits of cleanliness is obstructed by defective supplies of water. The annual loss of life from filth and bad ventilation are greater than the loss from death or wounds in any wars in which the country has been engaged in modern times.”

He recommended: “The expense of public drainage, of supplies of water laid on in houses, and of means of improved cleansing would be a pecuniary gain, by diminishing the existing charges attendant on sickness and premature mortality.”

German physician Johann Peter Frank, educated in France and Germany, was the founder of the holistic, modern system of hygiene and public health through his extensive commentary on the principles and practice on all aspects of hygiene and public health (water supply, sanitation, home hygiene, hospital hygiene, food safety, school health, sexual hygiene, maternal and child health and regulation).

In 1790 he spoke in Pavia, Italy and argued that poverty was the chief cause of diseases and that health conditions would not improve until the standard of living was raised. The modern curriculum for medical undergraduate education integrating health and hygiene was founded in Pavia in 1789.

Clean drinking water and cholera

It’s impossible for most of us to imagine what life would be like if our only source of drinking water was contaminated with diarrhoea from people dying of cholera. From the late 1820s the spread of cholera from India across Asia and continental Europe was the cause of much anxious speculation and comment but nobody knew for sure what caused it. Most people subscribed to the miasma theory, that stated diseases such as cholera were caused by pollution or a noxious form of ‘bad air’.

Some strange dietary and hygienic regimes came about as a result of the public speculation. For example in November 1831 The Lancet reported that a community of Jews in Wiesnitz had escaped the effects of cholera by rubbing their bodies with a liniment containing wine, vinegar, camphor powder, mustard, pepper, garlic and ground beetles.

And when cholera reached London in February 1832 many claims and suggestions as to how to avoid it were put forward – often by those hoping to make a profit. In one satirical print a man attempts to save himself by wearing and carrying a full range of protective equipment. This includes an acacia tree in his left hand and a juniper bush in his right, while having a branch of acorns near his mouth. He is also pictured with a pitcher of water behind each calf and pockets stuffed with herbs and perfumed tea.

The presence of strong smelling items reflects the prevailing belief that the source of disease was foul smelling air. The caption which describes all these methods ends with a warning: “By exactly following these instructions you may be certain that the cholera…will attack you first.”

It was only during a epidemic in Broad Street (now Broadwick Street), central London in 1854 that a physician called John Snow made a breakthrough. He was a sceptic of the miasma theory but the germ theory of disease had not yet been developed so he did not understand the mechanism by which the disease was transmitted. By talking to local residents Snow identified the source of the cholera outbreak as the public water pump.

Although his chemical and microscope examination of a water sample from the Broad Street pump did not conclusively prove its danger, his studies of the pattern of the disease were convincing enough to persuade the local council to disable the well pump by removing its handle. This action has been commonly credited as ending the outbreak, but Snow observed that the epidemic may have already been in decline.

Cluster of cases

Snow later used a dot map to illustrate the cluster of cholera cases around the pump. He also used statistics to illustrate the connection between the quality of the water source and cholera cases. He demonstrated that the water company was taking water from sewage-polluted sections of the River Thames and delivering it to homes – leading to cholera outbreaks. Snow's study was a major event in the history of public health and geography, and is regarded as the founding event of the science of epidemiology.

Researchers later discovered the public well in Broad Street had been dug only three feet from an old cesspit, which had begun to leak faecal bacteria. It was common at the time to have a cesspit under most homes and most families tried to have their raw sewage collected and dumped in the Thames to prevent it from filling faster than the sewage could decompose into the soil.

It was research scientist Louis Pasteur of France who carried out extensive experiments in the 19th century and first became convinced of the germ theory of disease, which states that germs attack the body from the outside. At the time it was generally felt that such tiny organisms could not kill larger ones such as humans. He is now recognised as being one of the greatest pioneers in the field of bacteriology.

German physician Robert Koch further developed Pasteur’s work and was able to directly link one microbe with a disease thanks to his detailed knowledge of the human body. He became famous for the discovery of the anthrax bacillus, the tuberculosis bacillus and the cholera vibrio. In 1881 he investigated basic methods for the evaluation of the efficacy of disinfectants and in 1885 became professor for hygiene at the University of Berlin.

Universally acknowledged

The role of hygiene in maintaining public health gradually became universally acknowledged and the first ever International Hygiene Exhibition took place in Dresden, Germany from May to October in 1911. With 30 countries participating, 100 buildings were constructed specially for the event, which attracted five-and-a-half million visitors. Afterwards many of the exhibits became part of the permanent German Hygiene Museum in Dresden.

As science has moved forward and we all learn more about how diseases are spread, and how effective hygiene practices can help to prevent their spread, we in the western world now take hygiene and cleanliness for granted. But we must not forget that public health has not reached the same standards in all parts of the world. For example 780 million (one in nine people) still do not have access to clean water. And 3.41 million people die from water, sanitation and hygiene-related causes each year according to the World Health Organisation (WHO).