Did London suffer a cholera outbreak – and did Queen Victoria meet Florence Nightingale?

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But how much of this is based on the truth? What do we know about this devastating cholera outbreak and Dr Snow's discoveries? Was the Queen actually concerned about the disease's spread? And where was Florence Nightingale in all this?

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The 1854 cholera outbreak in Soho, London

London had already experienced serious outbreaks of cholera in 1832 and 1849, but the events in series three of ITV drama Victoria focus on the Broad Street cholera outbreak of 1854 – a devastating event which killed more than 600 people and had huge consequences for the Victorians' understanding of the disease.

At this time, Soho was utterly filthy. The area was packed with people, cattle, slaughter houses, rotting material and bodily fluids. The rudimentary London sewer system had not reached the area, cesspools were overrunning, and the local water source was a pump drawing on a shallow public well dangerously close to all this human and animal waste.

What is cholera?

The classic symptom of cholera is large quantities of watery diarrhoea, often accompanied by muscle cramps and vomiting. The extreme fluid loss can lead to severe dehydration, resulting in sunken eyes and skin that is cold, clammy and bluish. Symptoms start suddenly and, without effective treatment, it kills about half of its victims.

The disease was poorly understood in the mid 19th century when the most popular theory (aside from divine punishment from God) was that cholera was caused by so-called "miasma", or "bad air". Public health officials and medical figures insisted that the disease was transmitted by particles in the air ("miasmata"), which appeared to explain why it broke out in smelly, poor neighbourhoods.

In reality, cholera is an infection of the small intestine, which is spread mostly by water and food contaminated by human faeces containing the bacteria vibrio cholerae. Exactly the kind of conditions found in Soho in the 1850s...

Who was Dr John Snow?

John Snow – no, not the Game of Thrones character or the Channel 4 newsreader – was the physician who famously traced the source of the Soho outbreak back to the public water pump on Broad Street.

Born to humble beginnings in York, Snow showed promise and became a medical apprentice at the age of just 14. Later he moved to London to receive a full and accredited medical education, and was able to set up a practice at 54 Frith Street in Soho.

Dr Snow became a rising star in anaesthesia – in fact, in 1853 he actually attended the Queen during the birth of Prince Leopold when, for the first time, she used chloroform as a pain reliever during childbirth.

"Dr Snow administered 'that blessed Chloroform' & the effect was soothing, quieting & delightful beyond measure," Victoria wrote.

But going against the medical establishment, he was sceptical about the miasma theory, particularly because the disease did not attack the lungs, but, instead, the digestive system and the bowels. When cholera broke out in 1854 he set out to collect evidence, mapping 13 public wells and all known cholera deaths, and talking to local residents about which pumps they had drunk water from. The "dot map" revealed a cluster of cases around the pump on Broad Street (now Broadwick Street).

Patterns on the "dot map" also confirmed his theory. There was a brewery (the Lion Brewery) one block east of the Broad Street pump, but none of its 70 workers had been struck down; this was because they could drink all the beer they wanted, and the fermentation used to make it killed the cholera bacteria. Similarly, a nearby workhouse was barely affected; Snow discovered that it had its own private well.

In another breakthrough moment, Snow found out about a widow living in Hampstead, who had died of cholera on 2nd September even though she had been nowhere near the "bad air" of Soho. When he interviewed the victim's son, he discovered that the widow loved the taste of the well water from the Broad Street pump so much that she sent her servant to Soho every day to fetch her a large bottle of water and bring it back to Hampstead. It wasn't the air which was giving people cholera; it was the water.

On 7th September Dr Snow took his findings to local officials and convinced them to take the handle off the pump, making it impossible to draw water. The outbreak came to an end – though the handle was ultimately replaced and locals went back to drinking the water.

Did the cholera outbreak end?

Despite Dr John Snow's findings and his presentation at the Medical Society of London, his views were rejected by the medical establishment.

It was only in the 1860s, with another cholera outbreak, that the "germ" theory of disease became more widely accepted. And in 1883 the bacterium vibrio cholerae was finally isolated by Robert Koch, who confirmed that cholera is spread through unsanitary water or food supply sources.

Sadly, Snow had died in 1858 after suffering a stroke at the age of 45, and never got to see his work widely accepted.

Was Queen Victoria worried about cholera?

Despite being a prolific diary-writer, Queen Victoria barely mentions the London outbreaks in her daily entries – although in 1849 she did note the spread of the disease with "40 to 50 dying daily of it." She also dismissed the Prime Minister's suggestion of a "Fast Day" intended to ward off the disease, calling it a "superstitious belief" and insisting that taking "necessary precautions" and praying to God would be a better solution.

The Soho outbreak of 1854 also does not feature in her journal; however, she closely followed the news about cholera among the troops fighting the Crimean War, which had just begun.

Did Florence Nightingale help with the cholera outbreak?

Florence Nightingale was a social reformer, statistician and founder of modern nursing who rose to fame during the Crimean War and became a national heroine in Victorian England.

Born in 1820 into a wealthy British family in Italy and educated to a high standard by her father William, Nightingale declared that she felt a calling to help the sick and poor, and wanted to become a nurse. Despite opposition from her family, at the age of 31 she was finally allowed to train in Germany.

She then became manager of a hospital for gentlewomen in London's Harley Street, but unlike the story we see on screen in ITV's Victoria, she does not seem to have been involved in caring for cholera sufferers in Soho during the outbreak.

In 1854, the Crimean War broke out. Nightingale was appointed Superintendent of the Female Nurses in the Hospitals in the East and put in charge of a group of nurses, who were sent to attend to wounded and sickly British troops in Turkey.

When they got there, Nightingale realised conditions were dire. Hospitals were very basic, overcrowded, and dirty; the soldiers were given little food or medicine, and suffered from cholera, dysentery and typhus. Doctors were initially resistant to her interference, but she and her nurses set about improving medical and sanitary arrangements, looking after nutrition, and washing clothes and bedding. She gained the nickname "the Lady with the Lamp" for walking between her patients' beds to check on them after dark.

Despite these efforts, the death rate still continued to rise, and it wasn't until the sewers and ventilation were improved at the hospital that the death rate actually dropped. Nightingale took these hygiene lessons to heart, though she retained her belief in the "miasma theory" until her death.

After the war, Nightingale returned to England. By now she was a hugely popular and admired figure, and she immediately began a campaign to improve the quality of nursing in military hospitals and elsewhere – writing books laying laying out the foundations of good practice and setting up a nursing college in London. She lived to the age of 90 and died in 1910.

Did Florence Nightingale have an owl?

Yup! Florence Nightingale did indeed have a pet owl, apparently rescued from some children tormenting the bird at the Parthenon in Athens, Greece. it was called Athena and travelled with her in her apron pocket.

After it died she had it stuffed, and it now resides at the Florence Nightingale Museum at St Thomas' Hospital in London.

Did Queen Victoria meet Florence Nightingale?

Yes, but not until later – and not in the midst of a cholera outbreak.

Queen Victoria first heard of Florence Nightingale in 1854, writing of this "remarkable person" who would be sent with a group of nurses to Scutari and Varna to care for soldiers during the Crimean War. She later received "touching accounts" from Nightingale, writing: "I envy her being able to do so much good & look after the noble brave heroes."

In fact, the Queen wrote notes and letters to Nightingale while she was abroad caring for the soldiers, and repeatedly expressed her admiration for her achievements.

When Nightingale returned, Queen Victoria invited her to Balmoral Castle in Scotland.

In her journal, Victoria wrote: "At 3 we received Miss Nightingale, the celebrated Florence Nightingale whom Sir J. Clark brought into the Drawing Room, leaving her with us for nearly an hour.

"It is impossible to say how much pleased we were with her. I had expected a rather cold, stiff, reserved person, instead of which, she is gentle, pleasing & engaging, most ladylike, & so clever, clear & comprehensive in her views of everything. Her mind is solely & entirely taken up with the one object, to which she has sacrificed her health, & devoted herself like a saint."