Explaining illness in the Middle Ages

In medieval Britain, most people had no idea what really caused disease. Explanations were a mix of the supernatural, religious and natural:

• Supernatural & religious — illness was a punishment from God, or caused by the alignment of the planets (astrology).
• Natural — the Theory of the Four Humours (from the Ancient Greek Hippocrates) and the ideas of Galen.

Key point: the Church was hugely powerful. It preserved and copied Ancient learning, but it also discouraged new ideas and largely blocked dissection, so old theories went unchallenged for centuries.

The Theory of the Four Humours

The Four Humours was the leading natural theory. It held that the body contained four liquids, and that illness came when these were out of balance.

Galen (a Greek/Roman doctor whose ideas dominated for over 1,000 years) built on this with the Theory of Opposites — treating an imbalance with its opposite (e.g. a "cold" illness with a "hot" food).

Which four?

How the sick were treated

Because the causes were misunderstood, medieval treatments rarely worked — but they made sense within the theories people believed:

• Bloodletting and purging — to remove "excess" humours and rebalance the body.
• Herbal remedies — mixed by "wise women", apothecaries or in the home.
• Prayer, pilgrimage and astrology — to appease God or read the stars.

Care often came from the home or from monasteries, which ran hospitals mainly to give rest, food and prayer rather than cures.

Islamic doctors and the Black Death

While Western Europe stood still, Islamic medicine was more advanced and preserved Ancient learning:

• Rhazes (al-Razi) — a great physician who wrote widely and distinguished diseases like smallpox from measles.
• Avicenna (Ibn Sina) — wrote "The Canon of Medicine", a huge medical textbook used in Europe for centuries.

Britain's greatest medieval health disaster was the Black Death (1348–49) — bubonic plague that killed perhaps a third of the population. People blamed God, bad air (miasma) and the humours, and could do little to stop it.

Public health: towns were dirty; efforts were basic — such as clearing rubbish or (during plague) trying to isolate the sick.

Name the book

The Medical Renaissance

From about 1500, the Renaissance ("rebirth") brought new curiosity, dissection and a willingness to challenge Galen. The printing press spread new ideas fast.

• Andreas Vesalius — through dissection he corrected Galen's mistakes about anatomy in his book "The Fabric of the Human Body" (1543).
• Ambroise Paré — a French army surgeon (16th century) who improved surgery: using ligatures to tie off blood vessels and a soothing ointment instead of hot oil on wounds.

Change was slow: these breakthroughs improved knowledge, but did not immediately cure patients — treatments still lagged behind for a long time.

Who corrected Galen's anatomy?

Harvey and the circulation of the blood

The Englishman William Harvey made one of the great discoveries of the Medical Renaissance. In 1628 he showed that blood circulates around the body, pumped by the heart.

This overturned Galen, who had wrongly taught that blood was constantly made in the liver and used up. Harvey's work was based on careful observation and experiment.

The Great Plague of 1665

Understanding of causes was still limited. When the Great Plague of London struck in 1665, people still had no real idea how plague spread.

• Many still blamed miasma (bad air), God, or the alignment of the planets.
• Responses were practical but unscientific — quarantine of infected houses, killing cats and dogs, carrying herbs and burning barrels of tar.

Compare: the Great Plague (1665) response was little more advanced than the Black Death (1348) — real progress on why disease spreads came much later, in the 1800s.

When did Harvey publish?

Jenner and vaccination

Smallpox was a terrible killer. The country doctor Edward Jenner noticed that milkmaids who caught the mild cowpox never seemed to get smallpox.

• In 1796 Jenner tested this by giving a boy cowpox, then exposing him to smallpox — the boy did not catch it.
• He called the method vaccination (from vacca, Latin for cow) and published his findings in 1798.

Why it mattered: Jenner's vaccine worked, but he could not explain why — germ theory was still decades away. Many doctors and the Church were suspicious at first.

Cholera and John Snow

Fast-growing, filthy industrial towns suffered deadly cholera epidemics from 1831 onwards. Most still blamed miasma.

In 1854 the doctor John Snow studied an outbreak in Soho, London. By mapping the deaths he showed they clustered around the Broad Street water pump — proving cholera spread through dirty water, not bad air.

How does cholera spread?

Pasteur and Koch: germ theory

The biggest turning point in medicine was proving that microbes (germs) cause disease — not bad air or humours.

• Louis Pasteur (French chemist) published his Germ Theory in 1861, showing that microbes in the air caused decay and disease.
• Robert Koch (German doctor) built on this to identify the specific microbes behind particular diseases — anthrax (1876), TB (1882) and cholera (1883).

Why it's the key breakthrough: once people knew germs caused disease, doctors could finally attack the real cause — leading to vaccines, antiseptics and better public health.

Fixing surgery: pain and infection

Before the mid-1800s, surgery meant terrible pain and deadly infection. Two breakthroughs changed this:

• Anaesthetics: James Simpson discovered that chloroform (1847) could safely put patients to sleep during operations.
• Antiseptics: using Pasteur's germ theory, Joseph Lister introduced carbolic acid from 1865/1867 to kill germs on wounds and instruments — cutting deaths from infection.

The "Black Period" of surgery: at first, pain-free surgery led to more ambitious, deeper operations — and so more deaths from infection, until Lister's antiseptics solved that problem too.

Cleaning up the towns

Industrial towns were overcrowded and filthy. Slowly, the government took action:

• Edwin Chadwick's Report (1842) exposed the link between dirt, poverty and disease.
• The first Public Health Act (1848) encouraged towns to improve sanitation — but was voluntary and weak.
• After the "Great Stink" (1858), engineer Joseph Bazalgette built London's great sewer system.
• The Public Health Act of 1875 made clean water, sewers and inspectors compulsory.

Why 1875 mattered: government moved from laissez-faire (leaving people alone) to actively protecting public health — a huge shift.

Who proved germs cause disease?

Person ↔ breakthrough

Tap a person on the left, then tap their breakthrough on the right.

"Magic bullets": the first cures for infection

Germ theory led scientists to hunt for chemicals that would kill the germ inside the body but leave the patient unharmed — "magic bullets":

• Paul Ehrlich's team found the first, Salvarsan 606, in 1909 — a cure for the disease syphilis.
• Prontosil, found by Gerhard Domagk in 1932, was the second magic bullet, effective against blood poisoning.

These were the first true chemical cures for infection — pointing the way towards antibiotics like penicillin.

Penicillin: the first antibiotic

The greatest breakthrough in fighting infection was penicillin — a story of chance, individuals, science and war:

• Alexander Fleming discovered penicillin by chance in 1928 — mould killing bacteria on a dish — but did not develop it.
• Florey and Chain turned it into a usable drug (~1940–41); it was mass-produced during World War II, saving countless lives.

Who discovered penicillin?

The NHS: healthcare for all

In the 20th century the government took charge of the nation's health. Building on early Liberal reforms and the wartime Beveridge Report (1942), which attacked the "five giants" including disease:

• The National Health Service (NHS) was founded on 5 July 1948, led by health minister Aneurin (Nye) Bevan.
• For the first time, healthcare was free at the point of use for everyone — doctors, hospitals and treatment paid for through taxation.

Why it matters: the NHS made the government fully responsible for everyone's health — the final step away from the medieval "God and the humours" world.

When was the NHS founded?

DNA and high-tech medicine

After the NHS, science and technology drove medicine forward at speed:

• In 1953, Watson and Crick (with Franklin and Wilkins) worked out the structure of DNA, opening the door to genetics and understanding inherited disease.
• High-tech medicine followed — scanners, transplants, keyhole surgery and new drugs.

Themes to spot: progress was driven by a mix of individuals, science and technology, war, government, communication and sometimes chance — the same factors run right through the whole 1000 years.

What drives medical change?

AQA rewards you for spotting the factors behind progress (and things that held it back):

Which factor?

Timeline: c1000 → present

Put the breakthroughs in order

Tap the breakthroughs in the correct time order, from earliest to latest.

Using sources on medicine

In the AQA exam you handle sources about health and medicine. Two quick habits win marks:

• Ask who made it and why (provenance). A doctor advertising his own cure and a modern textbook will describe the same treatment very differently.
• Use your own knowledge to judge it. Support or challenge a source with facts you know (dates, people, ideas — like germ theory or the four humours).

Context matters: a medieval writer blaming plague on God is not "stupid" — judge sources by what people could know at the time. That understanding is exactly what the exam rewards.

Thinking like a historian

How medicine changed over 1000 years

No single cause — but a chain of shifts, driven above all by the arrival of science and the growing role of government:

Science (especially germ theory) explained the real causes of disease; government then took responsibility for the nation's health, ending with the NHS.

The essentials to remember

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