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What Causes Illness and How is it Treated? 8000 BC : Prehistoric Cave paintings and symbolic artefacts found by archaeologists suggest the earliest humans believed in spirits and supernatural forces. Animals, the stars, the land in which they lived and dead ancestors all inhabited a spirit world that was connected to their everyday life. Special individuals, like Shaman, were thought to be able to contact the spirit world and seek their guidance when they entered mysterious trances. These men and women would call upon the spirits to bring good hunting or heal the sick and were possibly the first doctors. Spirit healers would perform ceremonies and cast spells to treat the sick. We also believe that they dispensed the first medicines. Drinking the blood of a wild animal killed in the hunt would give hunters special powers or eating special plants known only to the shaman could treat sickness. It is possible that these treatments would sometimes have a beneficial effect and it is thought that drugs like digitalis and morphine were first discovered in this way. 2000 BC : Egyptians Religious beliefs dominated the ancient Egyptians' view of healing. Doctors were often priests who were able to communicate with the gods responsible for the health of different parts of the body. Illness was due to the presence of evil spirits or poisons and removing these from the body with prayers to the gods would cure the disease. Medicines were used to help relieve pain but were not thought to play any other role in the healing process. As today, the Egyptians suffered from the common cold. Here is a remedy taken from an ancient papyrus: To make them feel better, the patient should be given the milk of a mother who has given birth to a boy. The following spell was to be made to get rid of the cold: May you flow out, catarrh, son of catarrh, who breaks the bones, who destroys the skull, who hacks in the marrow, who causes the seven openings in the head to ache. The Egyptians had doctors who specialised in treating particular parts of the body as well as researching the properties of herbal medicines. Their detailed records of the symptoms and treatments of illnesses formed some of the first medical textbooks. Egyptologists have found documents, written on a type of paper called papyrus, that describe medical techniques similar to those used today. The Egyptians used compression on a wound to stop bleeding and had specialists in obstetrics and gynaecology who were the forerunners of modern midwives. Egyptians believed in an afterlife. They mummified the bodies of Pharaohs and important people. Embalmers would carefully remove body organs, which were preserved in jars and buried with the mummified body. They would have gained knowledge of the internal structure of the body but this was not seen as important in the treatment of diseases, which were thought to be caused by the gods. What Causes Illness and How is it Treated? 450 BC to 300 AD : Greeks and Romans Greece was home to one of the earliest civilisations. Writing, mathematics, philosophy and the arts all flourished. The Greeks believed in many different gods but they also tried to understand their world in a much more scientific way. Possibly the most famous name in medicine belongs to the Greek philosopher Hippocrates. He is seen as the father of modern medicine and gives his name to the Hippocratic oath that doctors take. At this time, most people believed that diseases were sent as a punishment from the gods. Treatments were aimed at pleasing the gods so that the disease would be cured. Hippocrates went against this conventional thinking and looked on the body as having a balance between four humours: blood, phlegm, black bile, and yellow bile. If a person was ill, it meant that there was an imbalance in their humours and so they would take a treatment to return the balance back to normal. This often included bleeding or induced vomiting. This radical approach took medicine out of the spiritual world and the four humours formed the basis of medical treatments well into medieval times. Blood: gave a person a lively personality and lots of energy. They enjoyed life and the arts. Phlegm: made a person feel lethargic or have a dull personality. Black bile: caused depression and sadness. Yellow bile: influenced a person's temperament. It caused anger and a fiery temper. It is unusual to think of doctors working like this but in Greek times, the workings of the body remained very much undiscovered. We no longer believe in the four humours but many Greek practices still remain today. Greek physicians would talk to their patients to take careful case histories and find out as much from the patient as possible about their disorder. They would then examine them carefully to make a considered diagnosis of the problem before recommending a course of treatment. This method of examination and diagnosis is the basis of modern treatments. The Romans realised that there was a link between dirt and disease. To improve public health, they built aqueducts to supply clean drinking water and sewers to remove wastes safely. Improved personal hygiene helped to reduce disease and Roman baths were places to socialise as well as stay clean. What Causes Illness and How is it Treated? 500 - 1400 AD : The Middle Ages The fall of the Roman Empire meant that many of their public hygiene practices were soon lost. The Middle Ages in Europe saw most people without access to clean drinking water, regular bathing or a sewage system. This meant that health conditions were often worse than during the Roman occupation of earlier centuries. Most people were farmers and food was not as plentiful as today. Starvation and disease were common. Medicine in the middle ages was dominated by religion. Sickness was believed to be a punishment from God for sins committed and the only way to cure someone was to pray for their forgiveness. Doctors in the middle ages were usually priests or other religious scholars. Hospitals often sprang up in monasteries and other religious establishments. The patients were given food and comforted by religious nursing staff but little else was done to cure their illness. Traditional cures, using herbal remedies and potions were seen as witchcraft and outlawed by the church. Laws stated that only trained and registered people could practice medicine. Schools and universities began to educate wealthy individuals in religion, the arts, law and medicine. Generally men, and occasionally a few women, were trained and allowed to become physicians. As universities developed, more and more came from a non-religious background and eventually it was not necessary to be a cleric to practice medicine. The biggest challenge to medieval medicine came in the form of the Black Death, or Bubonic Plague. In 1347, an outbreak of bubonic plague broke out in Istanbul (modern day Turkey). Traders soon carried the disease throughout Europe and records show that in some areas it killed up to 90% of the population. That is the equivalent of 49 million people in the UK today. We now know that bubonic plague is a form of highly contagious and fatal pneumonia. During the middle ages, the only treatments were superstitious remedies, prayer, herbal medicines and recipes for clearing the air of miasma (poison). The plague was considered to be a punishment from God and so public health was not considered important. There was never any attempt to control the many rats that infested villages and towns and carried the disease (1 of the main reasons the plague was so devastating). Ibn Sina (Avicenna) wrote a book of healing in 1010 700 - 1500 AD : Arabic Medicines For many centuries after the fall of the Roman Empire, the Arabic world was the centre of scientific and medical knowledge. Texts from Greece and Rome were translated into Arabic and studied by Islamic scholars. They developed and refined Hippocrates’ theories and Islamic physicians began to use the regulation of diet, exercise and the prescription of medicinal herbs in the treatment of their patients. Arabic pharmacists became skilled in the formulation of medicines from plants and minerals. Even though they did not know about microbes, they used alcohol to clean wounds, which healed better and did not become infected. Hospitals were not just for the wealthy. They treated rich and poor alike. Islamic hospitals of the time would not look out of place today, with medical and surgical wards as well as operating theatres and pharmacies for the dispensing of medicines. By 931 AD, large hospitals were involved in the training and licensing of doctors and pharmacists. Officials tested medicines to certify that they were safe and visited pharmacists to make sure that prescriptions were being made correctly. All this was at the time when medicine in Europe was still governed by religion and superstition. What Causes Illness and How is it Treated? 1400 – 1700 : The Renaissance The Renaissance was a period in European history during which there was a revival in the ideas of ancient Rome and Greece. Aristocrats and scholars, who prized themselves on their education, studied culture, art, science and medicine. Ideas flourished and the newly invented printing press allowed books to be produced quickly. Before this, books were slowly and painstakingly copied by hand. Although very few people could read and write, the printing press was a revolution in information technology and resulted in ideas spreading around Europe like never before. It is hard to believe its impact but the printing press was the information superhighway of its day. Medicine remained dominated by the teachings of the church but physicians began to learn more about the human body. They read books translated from Arabic medical texts and began to study anatomy in a scientific and systematic way. Leonardo Da Vinci dissected human bodies and made the first anatomical drawings (see right). During this time, the human body was regarded as a creation of God and the ancient Greek view of the four humours prevailed. Sickness was due to an imbalance in these humours and treatments, such as bleeding the patient or inducing vomiting, were aimed at restoring the balance of these four humours. As the understanding of the body increased, so did the development of new medicines. Building on knowledge of herbs and minerals taken from Arabic writings, Renaissance pharmacists (or apothecaries) experimented with new plants brought from distant lands by explorers like Christopher Columbus. The bark of the Quina tree contained an ingredient called quinine, which is still used in the treatment of malaria. The leaves of the tobacco plant were thought to have medicinal properties, although we now know it is responsible for an enormous number of deaths. Laudanum, an opium-based painkiller, was prescribed for many disorders and remained in use up until Victorian times. However, progress was slow and many medicines remained little more than superstitious potions containing ingredients like worm's livers and tongue of newt. As new continents were explored, and trade between different parts of the world increased, it allowed the global spread of disease. This often had devastating effects as whole populations were exposed to pathogens against which they had no natural immunity. Bubonic plague moved along trade routes from China and killed more than a third of Europe's population. When the Spanish colonised South America, they brought smallpox, which killed many native Aztecs and Incas. Up until this time the prevailing view was that life arose from Spontaneous Generation. E.g. maggots arise in this way from rotting meat. In 1668 Francesco Redi tested this by putting meat in jars with and without corks (that excluded flies). Maggots only appeared in the open container. A more refined view of the Scientific method developed out of the ensuing furore. In just this way, people's understanding of the body increased tremendously and finally dispelled ideas that had remained from ancient Greek times. Scientific knowledge spread rapidly because scientists began to publish their work in books. In 1661 the Italian scientist Marcello Malpighi identified capillaries, which finally showed the link between arteries and veins and proving Harvey's theory for the circulation of blood. A Dutch clockmaker, Anton Van Leeuwenhoek, made one of the earliest microscopes to use a glass lens in 1677 he later saw, but did not recognise, bacteria. The detail the revolutionary microscopes could see allowed the English scientist Robert Hooke to observe cells for the first time. What Causes Illness and How is it Treated? 1700 – 1900 : 18th and 19th centuries Part 2 The industrial revolution of the 18th and 19th centuries saw a massive change in the way people lived and how this affected their health. People moved from small villages and an agricultural lifestyle to live in towns and cities that sprang up around the new factories, where they could work. People lived in dirty, overcrowded conditions with poor sanitation and dirty drinking water. Many died from diseases such as cholera, tuberculosis, and pneumonia – infections that could spread quickly and easily in these conditions. One of the big medical advances of this time was vaccination. Edward Jenner pioneered the earliest vaccinations and discoveries by Louis Pasteur and Robert Koch led to the understanding that infections were caused by certain bacteria or germs. The study of microbes, or microbiology, was born and the increased knowledge of pathogenic microbes led to the development of new medicines to tackle infectious diseases. The pharmaceutical industry was born. Louis Pasteur demonstrated that fermentation is caused by the growth of microorganisms, and that bacteria do not arise by spontaneous generation. His research also showed that the growth of microorganisms was responsible for spoiling beverages, such as beer, wine and milk. With this established, Pasteur invented a process in which liquids such as milk were heated to kill most bacteria and moulds already present within them. This process is now known as pasteurization. Beverage contamination in 1857 led Pasteur to the idea that microorganisms infecting animals and humans could cause disease. He proposed preventing the entry of microorganisms into the human body, which got Joseph Lister thinking. Joseph Lister realised that infections caught during an operation often lead to death by septicaemia. He pioneered the use of carbolic acid as the first antiseptic to clean wounds and surgical instruments. Operations were performed with a fine spray of carbolic acid passed over the patient to kill any microbes in the air. In one Newcastle hospital, use of Lister's antiseptic technique reduced deaths from infection from nearly 60% down to just 4%. Pasteur was convinced that microbes caused diseases in humans but he was never able to directly link one microbe with a disease. Robert Koch succeeded in doing this with anthrax, TB and blood poisoning. To do this he would isolate the suspected microbe from a diseased victim, culture it, infect a healthy host, which then got the disease, then isolate the same germ from the new victim. These steps comprise Koch’s Postulates. Perhaps the most famous nurse ever, Florence Nightingale, worked in a military hospital during the Crimean war. Conditions were poor and 80% of soldiers died from infections they caught in the hospital rather than their original wounds. Florence Nightingale improved standards of hygiene and sanitation, which dramatically reduced the infections in her hospital. When she returned from the war, Florence Nightingale embarked on a campaign to modernise and improve hospitals. She set the foundations of hospital design and nursing practice that are still seen today. What Causes Illness and How is it Treated? 1700 – 1900 : 18th and 19th centuries Part 1 Smallpox was a killer disease in the 18th century. Infected people became covered in horrible skin sores and often die a painful death. Those who recovered were left with terrible scars or pockmarks on their skin. We now understand that it is caused by the Variola virus. It infects the internal organs, causing severe blistering of the skin and death due to blood poisoning or secondary infections. Edward Jenner is credited with the development of vaccination but in fact it was first introduced into England by Lady Mary Wortley Montagu in 1721. She tried a method that was used in Turkey where people deliberately infected themselves with a mild form of smallpox. This was the first form of innoculation. Sadly, many people died from the smallpox they were using to protect themselves. Clearly something different needed to be done. Jenner was a doctor who worked in Gloucestershire and the great advance he made was to notice that individuals who had contracted cowpox (the cow's equivalent of smallpox) rarely caught the deadly human version. In 1796 he deliberately infected an eight-year-old boy called James Phipps with the pus from a cowpox sore. The boy became ill with cowpox but recovered. He then infected him with the normally deadly smallpox. As Jenner had predicted the earlier infection with the cowpox actually protected the boy who never caught smallpox. The practice of modern vaccination was born. Jenner’s results were met with scepticism and many doctors still carried out the more dangerous practice of innoculation with live smallpox pus. Eventually this dangerous practice was banned and in 1853 vaccination by Jenner's method was made compulsory. Protestors argued against compulsory vaccination, saying that it limited their personal choice; a similar debate to the one raging today over the MMR vaccine. Nearly 200 years after Jenner's discovery, a programme of vaccination by the World Health Organisation (WHO) was started with the aim to completely eradicate the smallpox virus. It is estimated that smallpox killed 500 million people worldwide during the last century. The last case of naturally transmitted smallpox was reported in Africa, in 1977. In 1980, the WHO officially announced the end of smallpox. There remain two highly guarded stocks of the virus in laboratories in the USA and Russia. These are preserved for research purposes. Some authorities speculate that other laboratories have stocks that could be used in germ warfare but these claims are yet to be proven. What Causes Illness and How is it Treated? 1900 - 2000: The 20th century In 1901, the average life expectancy in the Britain was 47 years. By the year 2000 it had risen to 77 years. New medicines, improved air quality and better public hygiene have contributed to this 64% increase in the life expectancy. The twentieth century has seen some major advances in healthcare, including the development of penicillin and antibiotics. After being first described by Edward Jenner in the 18th century, mass vaccination programmes were undertaken to prevent deaths from diseases such as yellow fever, poliomyelitis, measles, mumps and rubella. In 1980 the World Health Organisation announced that the deadly smallpox virus had been completely eradicated. Sadly, diseases like HIV/AIDS, cholera, tuberculosis, pneumonia and malaria remain major killers in third world countries where he levels of healthcare are below those found in the more well off Western nations At the start of the 20th century, many people still died from infectious diseases that today are easily cured. It was a discovery by Alexander Fleming in 1928 that would lead to the range of modern treatments for such diseases. In 1871, Joseph Lister noticed that some moulds could make other microbes grow more weakly. He did not realise the potential of this observation and did not follow it any further. It was over fifty years later, in 1928, that Alexander Fleming made a similar observation. Fleming was trying to find ways of killing the bacteria that caused cuts and wounds to become infected and turn septic. This was a serious condition and could cause death if the infection spread to the blood. He noticed that the growth of bacteria had been inhibited on a petri dish that had been accidentally contaminated with the mould Penicillium Notatum. He immediately realised that the mould must be producing a chemical that prevented the bacteria from growing. He cultivated the mould and investigated its properties on bacteria that caused diseases such as anthrax, meningitis and diphtheria. Fleming's discovery was not fully exploited until the outbreak of World War II in 1939. Infected wounds had caused many deaths in previous wars and two researchers from Oxford University, Howard Florey and Ernst Chain, set out to find new medicines to treat wounded soldiers. They realised the importance of Fleming's work and had the resources to grow large amounts of the Penicillium mould. This allowed them to isolate the active antibiotic in sufficient quantities to try it on patients suffering from severe infections. Before antibiotics, a simple throat infection could easily spread to the lungs and throughout the body. There was little that could be done for these patients and many died from complications of what we would now think of as a trivial infection. Florey and Chain showed that Penicillin could be used to save lives. The production of Penicillin became a wartime priority and pharmaceutical factories in the USA, United Kingdom and Russia manufactured large quantities of Penicillin, which was used to save the lives of wounded soldiers. There are now many different types of antibiotics, which are specialised to treat a wide range of bacterial infections. However, the widespread, and sometimes unnecessary use of antibiotics is leading to the evolution of strains of bacteria that are able to survive all but the most powerful antibiotics. These socalled superbugs can cause real problems, especially in hospitals where patients may become infected after surgery if the highest standards of hygiene are not maintained. Suggestions Put the class into 7 groups and give each group a different era to investigate. All students will need a copy of the sheets for their era. Some groups have 2 era, some have 1. The students need to read through the sheet and make sure everyone understands the terms (scientific / biological dictionaries may be useful). They try to answer the 2 questions at the top for each of the eras on their sheet. Then discuss any interesting/unexpected things that came up in their reading. Each group feeds back their findings to the class – key ideas only – in chronological order. Students could record a timeline of key people or key understandings. Some questions that may foster discussion: 1. In 2003 a new viral disease emerged called Severe Acute Respiratory Syndrome or SARS. How would an outbreak like SARS be treated in modern times compared to medieval times? 2. How did medical procedures in the Arab world compare with those in Europe during the Middle Ages? 3. How did explorers affect the development of medicine and also the new peoples that they visited? 4. How did the living conditions in towns affect the health of people living there? 5. Suggest some medical developments which improve the quality of health and life, rather than being only life-saving. 6. What does this activity tell you about the work of scientists?