Medieval ideas about disease

In the Middle Ages people did not know that germs cause disease. Their main ideas were:

• Supernatural: illness was a punishment from God, so prayer and pilgrimage were "cures".
• The Theory of the Four Humours (from the ancient Greek Hippocrates and later Galen): health meant balancing blood, phlegm, yellow bile and black bile — so doctors used bloodletting and purging.
• Miasma: "bad air" or bad smells were thought to spread disease.

Key idea: the Church protected the old ideas of Galen, which slowed new discoveries — but monasteries did run hospitals and keep learning alive.

The Black Death

The Black Death reached England in 1348 and killed perhaps a third or more of the population. People had no idea what really caused it.

• Causes people believed: God's punishment, bad air (miasma), the planets, or the humours out of balance.
• "Cures" and responses: prayer, lucky charms, herbs, fleeing the towns — none of which worked.

The Black Death shows medieval medicine at its limits: with no germ theory, people could neither explain nor stop the plague.

Balancing the body

The Renaissance: new knowledge

From the 1500s, careful observation began to challenge old ideas:

• Andreas Vesalius improved knowledge of anatomy, correcting Galen's mistakes (On the Fabric of the Human Body, 1543).
• William Harvey proved that the heart pumps blood around the body in a circulation (1628).

These men did not cure many diseases directly, but they showed doctors should test and observe rather than simply trust old books — a vital shift in how medicine progressed.

Jenner and vaccination

In 1796, the country doctor Edward Jenner showed that infecting someone with the mild disease cowpox protected them against the deadly smallpox.

• Jenner tested his idea and published it — this was the first vaccination.
• He did not know why it worked (germs were not yet understood), but it saved countless lives.
• Vaccination was made compulsory for smallpox in Britain in the 1850s.

Smallpox was eventually declared eradicated worldwide in 1980 — a direct descendant of Jenner's discovery.

Name the vaccination pioneer

Pasteur, Koch and Germ Theory

The greatest breakthrough was proving that microbes (germs) cause disease:

• Louis Pasteur published his Germ Theory in 1861, showing microbes — not bad air — cause decay and disease.
• Robert Koch identified the specific bacteria behind diseases such as TB and cholera in the 1880s.

Germ Theory transformed medicine: at last people understood why disease spread, which made prevention and cures possible.

Pain, infection and bleeding

Before the 19th century, surgery was agonising and deadly. Three great problems were solved:

• Pain — anaesthetics: chloroform was introduced by James Simpson in 1847, letting surgeons operate without agony.
• Infection — antiseptics: Joseph Lister used carbolic acid from 1865 to kill germs during operations.
• Blood loss: safe blood transfusion became possible after blood groups were discovered in 1901.

Together, anaesthetics and antiseptics made longer, deeper and safer surgery possible for the first time.

Who proved germs cause disease?

The year of Germ Theory

Cleaning up the towns

Fast-growing industrial cities were filthy and disease-ridden. Cholera outbreaks forced governments to act:

• John Snow proved in 1854 that cholera spread through dirty water, not bad air, by tracing an outbreak to a pump in Broad Street, London.
• The 1848 Public Health Act (and the much stronger 1875 Public Health Act) forced towns to provide clean water, sewers and drainage.
• The great London sewer system was built by Joseph Bazalgette in the 1860s.

Government moved from "laissez-faire" (leaving things alone) to actively protecting public health — a huge change.

Pioneer ↔ breakthrough

Tap a person or event on the left, then tap the correct breakthrough on the right.

Fleming and penicillin

In 1928, Alexander Fleming noticed that a mould, penicillin, killed bacteria in his laboratory — the first antibiotic.

• Fleming could not make enough of it, so his discovery was nearly forgotten.
• In the early 1940s, Florey and Chain developed a way to mass-produce penicillin, especially to treat wounded soldiers in the Second World War.

Antibiotics could finally cure bacterial infections that had killed for centuries — one of the greatest advances in all medicine.

The National Health Service

Before 1948, many people could not afford a doctor. The National Health Service (NHS) was founded in 1948, led by Health Minister Aneurin (Nye) Bevan.

• It provided healthcare free at the point of use for everyone, paid for through taxes.
• It followed the wartime Beveridge Report (1942), which promised to fight the "giant evils", including disease.

The NHS meant that, for the first time, good medical care did not depend on how rich you were — a landmark in improving national health.

The year of the NHS

Fighting infection in surgery

Timeline: c.500 → today

Put the breakthroughs in order

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

Name the antibiotic pioneer

Change, continuity and sources

This thematic study rewards you for tracking change and continuity over time and judging sources and interpretations:

• Ask what drives change: science and technology, key individuals, war, government and communication.
• Note continuity: ideas like the humours lasted for over 1,500 years before Germ Theory replaced them.
• Judge sources by who made them and why (provenance) before trusting them.

Interpretations differ: some historians stress sudden "revolutions" (Germ Theory); others stress how slowly ideas actually spread.

Thinking like a historian

Cholera and clean water

The theme in one line

Across 1,500 years, medicine moved from guesswork and religion to science and prevention — with government and the NHS finally making good care available to everyone.

The essentials to remember

You've covered the whole Eduqas Health and Medicine, c.500 to the present day thematic study. Press Finish to see your score.