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Spanish Flu Pandemic 1918 - Could It Happen Again?
A warehouse being used as a makeshift hospital for flu patients in 1918
It is 100 years since the influenza pandemic killed millions around the world, a death toll far worse than the bubonic plague. But what is the chance of something similar happening again? New strains of flu continue to emerge and experts warn that another pandemic could happen despite a century of advances in technology and healthcare.
During the 1918-19 outbreak, it was thought that Spanish flu was caused by bacteria rather than a virus. Viruses are now better understood, but scientists have also learned a great deal from studying the pandemic which struck a century ago.
A coloured transmission electron micrograph of A strain H5N1
They learned how very differently it could behave to our usual experience of seasonal flu. It hit proportionately more younger and healthier adults. Experts believe older people who were infected by Spanish flu may have previously encountered a similar strain, and therefore had a degree of immunity.
Dr Niall Johnson, who published a study of the 1918-19 pandemic says the medical profession a century ago was familiar with infectious disease, but not at this scale.
"Many of the medical memoirs mention the pandemic, and often say that it was not the presentation of the disease that was unusual but the sheer volume of cases - and how little they could offer people," he said.
Drawings from 1918 by John George Adami of (right) the trachea showing earliest stage of reaction in influenza and (left) the main bronchus of a set of lungs
Dr Jonathan D Quick is an expert on epidemics worldwide and is working to help nations prepare better.
"With some flu viruses - it was true in 1918 and in 2009 - one of things which happens is that the way that flu kills you is not the flu itself," he said. "It's what it does to your lungs, it sort of melts the linings and then you get a bacterial pneumonia... That will kill you.
"They didn't have antibiotics then, so they died faster. But the other thing that happens, particularly in young people when they have a good, active immune system is that your body overreacts. It ends up just filling your lungs with fluid. A lot of these deaths weren't from the bacterial complications, but from an explosion of the immune system."
Dr Johnson says the impact of new viruses today will vary, for several reasons. These include vaccines that may confer some immunity, anti-viral drugs, better hygiene and antimicrobials that deal with the infections such as pneumonia, that were major contributors to the death rate in the 1918-19.
"So, yes, I think we are better placed than in 1918 but the potential for a pandemic to be a global infection that sickens the majority of the world's population and kills a substantial number is still there."
Dr Quick believes such a scenario is not inevitable, if more is done to make the world safer and prepared.
"One of the most important things is to invest in the so-called universal flu vaccine," he says - one which works against all strains of the virus, by targeting the part of the virus which doesn't change.
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The UK government sets out an official National Risk Register, which says that no country is immune to infectious disease from another part of the world. It estimates that in the event of pandemic flu:
Dr Quick believes the UK is the only country to report risk in this way.
Dr Jonathan D Quick is asked are we complacent about the chances of a flu pandemic reoccurring
But globally, are we still complacent?
"Absolutely," he says. "I believe we're just as vulnerable today to big flu as we had in 1918 but for different reasons. So today we have four times the population, we are twice as urbanised, and that crowding has been a factor in recent Ebola outbreaks, and is a factor in flu.
"We are 50 times as mobile - so we're in the air, travelling across borders, there isn't any place on the planet which is more than 24 to 36 hours away from any major city."
He says flu is tricky, a virus that keeps mutating and exchanging genes.
"With all of those risk factors in play, we could have an epidemic with a new virus that has mutated and that we don't have immunity to," he says.
"We could have an outbreak which could kill between 200 and 400m in the matter of a couple of years and knock the global economy as badly as the Great Recession."
The experiment tracked people's movements and interactions to predict how a pandemic might spread
Predicting the path of a pandemic
The BBC Four Pandemic experiment, with mathematicians from Cambridge University, involved nearly 29,000 people downloading an app to track their movements and social interactions to predict how a pandemic might spread.
Their modelling predicted that:
Dr Meirion Evans, a recently retired consultant epidemiologist at Public Health Wales, believes the key is vigilance and sharing data - underpinned by a global surveillance system which is coordinated by the World Health Organisation (WHO).
"Linked to that is a global virology network... When there's an incident, the local specialist laboratory will isolate, identify and type these viruses to work out if it's something new, or if it's not, what virus it is related to," he said.
Technology could also help. Dr Quick points to the web crawler created by Public Health Canada which harvested news of the SARS outbreak as it showed itself in China.
Archive advertisements associated with flu and remedies
We have come a long way from old newspaper adverts, offering cure-all remedies, old wives' tales and simple hope. But there are lessons still to learn - and we underestimate flu at our peril.
"If anyone doubts it, humanity has not escaped infectious disease," says Dr Johnson. "In the mid-20th Century some people rather hubristically claimed we'd beaten infectious disease. HIV, multi-drug-resistant TB, flu, Ebola all put pay to that.
"Flu is particularly interesting due to its ability to change, and our continuing inability to find vaccines that work against more than specific strains".
It is impossible to tell when the next pandemic flu may occur - in 25 years or next year.
Although a rare occurrence, Dr Quick says in the meantime we must be ready for it at the highest level.
"There needs to be that vigilance and the willingness of leaders to open their eyes - because delays are deadly - respond to the immediate epidemic and then once the panic's gone, keep promises about investing in preventing the next one; it's that leadership."
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Inside The Swift, Deadly History Of The Spanish Flu Pandemic
Scientist Johan Hultin traveled to Brevig Mission, Alaska, a town of a few hundred souls in the summer of 1997. He was searching for buried bodies, and Alaska's frozen ground was the perfect place to find them. Digging through the permafrost—with permission from the town's authorities—he eventually uncovered a woman who died almost 80 years previously and was in a state of excellent preservation. Hultin then extracted samples of the woman's lung before reinterring her. He intended to use this to decode the genetic sequence of the virus that had killed this Inuit woman along with 90 percent of the town's population.
Brevig Mission was just one place that was part of a global tragedy, one of the worst ever to befall humanity: the influenza pandemic of 1918-19. The outbreak of this influenza virus, also known as Spanish flu, spread with astonishing speed around the world, overwhelming India, and reaching Australia and the remote Pacific islands. In just 18 months at least a third of the world's population was infected. Estimates on the exact number of fatalities vary wildly, from 20 million to 50 million to 100 million deaths. If the upper end of that estimate is accurate, the 1918 pandemic killed more people than both World Wars put together. (Get the facts on influenza.)
The first official cases of the 1918 Spanish flu pandemic were recorded at the U.S. Army's Camp Funston, Kansas, where this emergency influenza ward held treated patients.
SPL/AGE FOTOSTOCK
War and pestilenceSeveral closely related viruses cause influenza, but one strain (type A) is linked to deadly epidemics. The 1918-19 pandemic was caused by an influenza A virus known as H1N1. Despite becoming known as the Spanish flu, the first recorded cases were in the United States in the final year of World War I. (Explore the memorials of World War I.)
A magnified view of the H1N1 virus responsible for the 1918 pandemic.
SPL/AGE FOTOSTOCK
By March 1918 the United States had been at war with Germany and the Central Powers for 11 months. During that time America's small, prewar army had grown into a vast fighting force that would eventually send more than two million men to Europe. (How the United States entered World War I.)
American forts experienced a massive expansion as the entire nation mobilized for war. One of these was Fort Riley, Kansas, where a new training facility, Camp Funston, was built to house some of the 50,000 men who would be inducted into the Army. It was here in early March that a feverish soldier reported to the infirmary. Within a few hours more than a hundred other soldiers had come down with a similar condition, and more would fall ill over the following weeks. In April more American troops arrived in Europe and brought the virus with them. The first wave of the pandemic had arrived. (What is the difference between an epidemic and a pandemic?)
Deadly speedThe Spanish flu strain killed its victims with a swiftness never seen before. In the United States stories abounded of people waking up sick and dying on their way to work. The symptoms were gruesome: Sufferers would develop a fever and become short of breath. Lack of oxygen meant their faces appeared tinged with blue. Hemorrhages filled the lungs with blood and caused catastrophic vomiting and nosebleeds, with victims drowning in their own fluids. Unlike so many strains of influenza before it, Spanish flu attacked not only the very young and the very old, but also healthy adults between the ages of 20 and 40.
Biologists at St. Bartholomew's Hospital in London are analyzing brain and lung tissue from victims of the 1918 pandemic as part of global efforts to understand the virus. Here, wax-mounted tissue samples sit on a list of children's names who fell victims to influenza in 1918.
SPL/AGE FOOTSTOCK
The principal factor in the virus's spread was, of course, the international conflict then in its last phase. Epidemiologists still dispute the exact origins of the virus, but there is some consensus it was the result of a genetic mutation that perhaps took place in China. But what is clear is that the new strain went global thanks to the massive and rapid movement of troops around the world.
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The drama of the war also served to obscure the unusually high mortality rates of the new virus. At this early stage, the illness was not well understood and deaths were often attributed to pneumonia. Strict wartime censorship meant that the European and North American press were unable to report outbreaks. Only in neutral Spain could the press speak freely about what was happening, and it was from this media coverage that the disease took its nickname.
Deadly ContactNative Americans treat patients infected by European diseases in this 1591 engraving by Theodor de Bry.
GRANGER/ALBUM
Epidemics are as old as civilization: Signs of smallpox appear on 12th-century B.C. Egyptian mummies. Increased contact led to the spread of disease. In the sixth century A.D. The Plague of Justinian moved along trade routes, killing 25 million people across Asia, Africa, Arabia, and Europe. Eight centuries later, the Black Death wiped out 60 percent of Europe's population. When Europeans settled in the Americas in the 16th and 17th centuries, they introduced smallpox, influenza, and measles to the native peoples, killing an estimated 90 percent of the population. Here, Native Americans treat patients infected by European diseases in a 1591 engraving by Theodor de Bry.
The second waveThe overcrowded trenches and encampments of the First World War became the perfect hosts for the disease. As troops moved, so the infection traveled with them. The wave that had first appeared in Kansas abated after a few weeks, but this was only a temporary reprieve. By September 1918 the epidemic was ready to enter its most lethal phase.
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Murder or madness: What really killed Edgar Allan Poe?It has been calculated that the 13 weeks between September and December 1918 constituted the most intense period, taking the greatest number of lives. At least 195,000 Americans died in October alone. In comparison, total American military casualties for the whole of World War I came in at just over 116,000. Once again, it was the crowded military encampments where the second wave initially gained a hold. In September an outbreak of 6,674 cases was reported at Camp Devens, a military base in Massachusetts.
As the crisis reached its zenith, the medical services began to be overwhelmed. Morticians and gravediggers struggled, and conducting individual funerals became impossible. Many of the dead ended up in mass graves. The end of 1918 brought a hiatus in the spread of the illness and January 1919 saw the beginning of the third and final phase. By then the disease was a much diminished force. The ferocity of the autumn and winter of the previous year was not repeated and mortality rates fell.
Although the final wave was much less lethal than its predecessors, it was still able to wreak considerable damage. Australia, which had quickly enacted quarantine restrictions, managed to escape the worst of the flu until the beginning of 1919, when the disease finally arrived and took the lives of several thousand Australians.
The Spanish flu did not strike in Australia until 1919. Quarantine camps like this one, in Wallangarra, Queensland, were set up to treat and contain the illness.
PAUL FEARN/ALAMY/ACI
The general trend of mortality, however, was downward. There were cases of deaths from influenza—possibly a different strain—as late as 1920, but by the summer of 1919 health care policies and the natural genetic mutation of the virus brought the epidemic to a close. Even so, its effects, for those left bereaved or suffering long-term health complications, were to last decades.
Lasting impactThe pandemic left almost no part of the world untouched. In Great Britain 228,000 people died. The United States lost as many as 675,000 people, Japan some 400,000. The south Pacific island of Western Samoa (modern-day Samoa) lost one-fifth of its population. Researchers estimate that in India alone, fatalities totaled between 12 and 17 million. Exact data in the number of deaths is elusive, but global mortality figures are estimated to have been between 10 and 20 percent of those who were infected.
In 1997 the samples taken by Johan Hultin from the woman found in the frozen mass grave in Brevig Mission added to scientists' knowledge as to how flu viruses mutate and spread. Drugs and improved public hygiene—in conjunction with international institutions such as the World Health Organization and national bodies such as the Centers for Disease Control and Prevention in the United States—put the international community in a much better position to meet the challenges of a new outbreak. However, scientists know a lethal mutation could occur at any time, and a century on from the mother of all pandemics, its effects on a crowded, interconnected world would be devastating.
Worldwide Flu Pandemic Strikes
Worldwide flu pandemic strikes1918 - 1919
Late in the spring of 1918 the Spanish wire service Agencia Fabra sent cables of an unusual nature to Reuter's news service headquarters in London. "A strange form of disease of epidemic character has appeared in Madrid," it said. "The epidemic is of a mild nature, no deaths having been reported." The illness began with a cough, then headache and backache, fatigue, high fever, racing heart, loss of appetite and labored breathing. It usually lasted about three days. Cases had cropped up over the spring and summer in other countries, too, from Norway to India, China to Costa Rica. But in Spain, suddenly 8 million people were down with the bug. And as the summer of 1918 turned to fall, the epidemic lost its mildness: people started to die.
The influenza commonly called "Spanish flu" killed more people than the guns of World War I. Estimates put the worldwide death toll at 21,642,274. Some one billion people were affected by the disease -- half of the total human population. It came at a time when 19 nations were at war and the disruption, stress, and privation of war certainly aided the flu's transmission. It killed people on every continent except Antarctica, with the most lives lost in Asia and the highest percentage of population killed in India. From August 1918, when cases of the flu started looking abnormally high, until the following July when they returned to about normal, 20 million Americans became sick and more than 500,000 died. In October, 1918, the flu reached its peak, killing about 195,000 Americans. About 57,000 American soldiers died from influenza while the U.S. Was at war; about 53,500 died in battle.
There wasn't much doctors could do. In the course of the epidemic nearly every known therapy was tried -- quinine tablets, bleeding, castor oil, digitalis, morphine, enemas, aspirin, tobacco, hot baths, cold baths, iron tonics, and expectorants of pine tar. Little was known about the virus, except that it was contagious. After deaths from the disease began in earnest, many local governing bodies closed down theaters, churches, and other public gatherings. Ordinances made it illegal to spit, cough, or sneeze in public -- with threat of $500 fines in New York City. When people went out they wore gauze masks over their nose and mouth, often soaked in camphor or other medicinal substances.
After months of terrorizing people around the world, the "Spanish lady" (called "The Naples Soldier" in Spain, and a variety of other names around the world) seemed to withdraw. It had been the most dire epidemic since the Middle Ages, the third worst in recorded history. For all its destruction, it did not get much press at the time. War and then peace monopolized the front pages. And still little is known about the origin or nature of the killer virus. Many believe the modern "swine flu" virus is a descendant of the deadly 1918 flu. Some theorize that its stronger ancestor ganged up with a bacteria to wreak havoc on the human population. In recent years, vaccinations against various strains of influenza have been introduced.
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