Nothing has killed more human beings than infectious disease – neither flood nor famine, not even war – and not just in ancient times. Two of the worst outbreaks in history struck in the 20th century and the Black Death is still with us.

Death from contagion has been in decline since the 1940s thanks to modern medicine but, as Covid-19 reminds us, murderous microbes haven’t gone away. Far from it, their number has seen a fourfold uptick in the last 50 years. The planet is hosting double the number of humans it did 50 years ago, and 12 times more livestock carrying infections that can leapfrog to us. We spread them around our crowded cities and take them on our travels with our carry-on luggage, allowing new pathogens to flourish where once they might have died out.

On the bright side, we have it better than in former times when only the rich could afford doctors and victims were forcibly isolated – nailed into their homes and left to die.

Bubonic Plague

Plague has been with us for 5,000 years, contributing to the fall of the Roman Empire, wiping out half the population of medieval Europe and still cropping up in isolated outposts.

It all started when infected black rats stowed away in grain shipments from Egypt, unleashing biblical infestations of fleas in Constantinople where humans and livestock lived cheek by jowl.

Between 541 and 750AD over 500 million people were literally bitten to death. Emperor Justinian 1 who gave his name to the first pandemic showed no mercy, not only taxing afflicted tenant farmers in full but charging them for rent owed by their dead neighbours.

It took another 800 years for the disease to travel the Silk Road to Europe where it was dubbed the Black Death after the colour of the egg-sized swellings. Homes stricken by plague were marked with crosses and death was hastened by ‘home cures’ – dead pigeon rubs, dung and urine poultices, self-flagellation… you couldn’t make it up but people did.

Plague resurfaced every 20 years for the next three centuries, culminating in a third pandemic which started in China in 1855, hitting India worst, and was still considered active until 1960.

Cause – Yersinia pestis bacteria

Symptoms – Black, swollen lymph glands (buboes) in the armpits, neck and groin. Could spread to the lungs and blood as pneumonic/septicemic plague, fatal if untreated.

Legacies – Quarantine: The practice originates from Black Death times when the world trade capital of Venice required ships from infected ports to remain at anchor offshore for 40 days – ‘quaranta giorni’ in Italian.

Antibiotics: French bacteriologist Alexandre Yersin isolated the plague bacillus in 1894 and Scottish microbiologist Alexander Fleming’s penicillin provided the silver bullet in 1928.

Plague Doctors

These beaked terrors with round glass eyes were your (slim) hope of survival from bubonic plague In the 17th century.

Hired by cities to treat rich and poor alike, many were quacks under their trademark wide-brimmed hats and Levantine leather overcoats. But though their spine-chilling ‘cures’, including bloodletting with leeches to ‘balance the humours’, rarely worked, their diligent note-taking is the reason we have such good historical records.

The costume, a precursor to PPE, was devised by Charles de Lorme, chief physician to the Medicis and three French kings. The hollow beak had slits for breathing and was filled with aromatic herbs and spices to stave off bad odours thought to be the root cause. A cane to keep patients at a distance and remove their clothing without contact completed the scary outfit.

If the mask looks familiar, it’s modelled on Il Medico della Peste, a character from Italy’s commedia dell’arte, worn all over Venice during Carnival Fortnight.

Smallpox

The killer virus first incubated by rodents 10,000 years ago and passed between humans via infectious respiratory droplets has claimed over half a billion lives down the centuries and its scars run deep. It saw off Egyptian Pharaoh Rameses V and Louis XV of France, left Queen Elizabeth 1 and Beethoven pockmarked for life, and shipped over with New World explorers to wreak genocide among native American Indian tribes.

In Europe it was scything down 400,000 victims a year when British doctor Edward Jenner discovered that milkmaids who’d had cowpox were immune and developed the first vaccine in 1796 (‘vacca’ is Latin for cow). But the global inoculation programme mounted by the World Health Authority in 1967 came too late to save the 500 million who succumbed to the scabrous killer during the last 100 years of its existence.

Technically the virus is still with us. Stocks are kept at high security labs in America and Russia, just in case the genie should escape from the bottle again.

Cause – Variola virus

Symptoms – Skin rash develops into fluid-filled pustules which scab and leave deep scars, causing blindness in rare cases. Babies and young children were the most vulnerable

Legacy – Herd Immunity: The eradication of smallpox in 1980 was one of the greatest triumphs in medical history – the first and only human disease to be stopped in its tracks by a vaccine. The campaign inspired immunisation programmes for many other major diseases including diphtheria, whooping cough, tetanus, polio, measles and TB.

Spanish Flu Pandemic

WW1 claimed 20 million lives, Spanish flu took more than double. ‘The greatest medical holocaust in history’ killed more people in 24 weeks than AIDS in 24 years and infected one third of the world’s population between January 1918 and December 1920. It struck when the world was still at war and spread in a vicious second wave as weak and malnourished troops returned home, many to die in their beds having survived four years in the trenches.

Healthy 20-40 year-olds also succumbed, possibly due to an overreaction of their immune systems, a theory coronavirus is now putting to the test. The Bishop of Zaragoza begged to differ, stating: “The evil hanging over us is a consequence of our sins and lack of gratitude, and that is why the vengeance of eternal justice has fallen upon us.”

But it was no more Spanish flu than Covid-19 is Chinese. There was no wartime censorship in neutral Spain and when King Alfonso XIII caught it the news went viral and the name stuck. The Spanish had their own name for it – el soldado de Nápoles (the Naples soldier) after a song in a popular operetta said to be as ‘catchy as the flu’.

Communities collapsed, healthcare workers were too ill to tend the sick, bodies were buried in mass graves and people took to home remedies, chewing cinnamon sticks, brewing up Oxo cube toddies and guzzling wine. Lockdowns were ad hoc but populations that kept the strictest social distancing made the fastest economic recovery.

The same virus returned with a vengeance in 2009. We called it swine flu.

Cause – H1N1 influenza virus

Symptoms – Hacking cough and fever that could turn into pneumonia, 99% of victims were under 65

Legacy – The electron microscope: invented in 1931, enabled the study of organisms too small to see before. The influenza vaccine followed in 1938. Today ‘flu shots’ are developed twice a year for the northern and southern hemispheres to take mutations into account.

Modern Plagues

Germs have got savvier and we’re fighting off their mutant forms like never before. Over 30 new diseases have emerged in the last three decades alone and 75% are ‘zoonotic’ (passed from animals to humans); SARS (Severe Acute Respiratory Syndrome) a coronavirus prevalent in horseshoe bats and civets, MERS its Middle East equivalent (bats, camels) Ebola and AIDS (fruit bats, chimpanzees), Zika (mosquitos) and Covid-19 (potentially bats, pangolins) are just some. Intensive farming, butchery, poaching and the illegal exotic pet and bush meat trades are bringing us closer to animals while climate change and habitat destruction is bringing them closer to us. Add our own global connectivity and you have a ticking time bomb that makes ‘squashing the sombrero’ – as Boris Johnson vividly described his bid to flatten the curve of the current outbreak – infinitely more challenging today.

The World Heath Authority reports one billion cases and millions of deaths from zoonoses every year, stating: “The lesson of our present time is that emerging zoonotic infections are unexpected and unpredictable events and that any disease outbreak anywhere today could be a problem for the world tomorrow.”

WORDS BELINDA BECKETT

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