As death toll from coronavirus soars a book details the last time a deadly Asian flu hit…

Health Secretary Matt Hancock this week declared the coronavirus outbreak a ‘serious and imminent’ threat to the British public.

More than 42,000 people have contracted the new strain — now named as COVID-19 — which originated in Wuhan, a city of 11 million people in central China, and there have been more than 1,000 deaths.

It is not, of course, the first highly contagious flu-like virus to start in Asia and spread fast — nor will it be the last.

In 2003, SARS (Severe Acute Respiratory Syndrome) — another coronavirus virus that was dubbed the Angel of Death — killed nearly 1,000 people before it abated. The new virus is proving to be more infectious than SARS, has caused more cases in a fraction of the time and now exceeds the number of fatalities (although SARS had a mortality rate of almost 10 per cent compared to 2 per cent for COVID-19).

But what did we learn from SARS, what is the role of the so-called super-spreaders, and how can we use that to stop this new strain?

Here, David Quammen, the author of an award-winning book about the SARS epidemic, draws on research by scientists worldwide —and his own detective work — to show the making of a potential pandemic. 

Back in late February 2003, SARS got on a plane in Hong Kong and went to Toronto. Its arrival in Canada was unheralded but then, within days, it began to make itself felt.

It killed the 78-year-old grandmother who had carried it into the country, killed her grown-up son a week later, and spread through the hospital where the son had received treatment.

Rather quickly it infected several hundred other Toronto residents, of whom 31 eventually died.

Cathay Pacific aircrew wear masks at Hong Kong’s Chek Lap Kok airport to protect against a killer outbreak Severe Acute Respiratory Syndrome (SARS) in April 2003

One of the infected was a 46-year-old Filipino woman, working in Ontario as a nursing assistant, who flew home to the Philippines for Easter, started feeling sick the day after arrival (but remained active, shopping and visiting relatives) — and began a new chain of infections on the island of Luzon.

So SARS had gone halfway around the world and back, in two airline leaps, over the course of six weeks.

No one could be sure, at that early stage, whether the SARS agent was a virus, a bacterium or something else. In the meantime, it had also arrived in Singapore, Vietnam, Thailand, Taiwan and Beijing. Singapore became another epicentre.

It reached Beijing by at least two modes of transport, one of which was China Airlines Flight 112, from Hong Kong, on March 15. (The other route was by car when a sick woman drove up from Shanxi province.)

Flight CA112 took off from Hong Kong that day carrying 120 people, including a feverish man with a worsening cough. By the time it landed in Beijing, three hours later, 22 other passengers and two crew members had received infectious doses of the coughing man’s germs.

A 90-year-old man is transported between hospitals during the SARS outbreak of March 2003 in Hamburg, Germany

A 90-year-old man is transported between hospitals during the SARS outbreak of March 2003 in Hamburg, Germany

From them it spread through more than 70 hospitals in Beijing — yes, 70 — infecting almost 400 staff, other patients and visitors.

Two aspects of what made SARS so threatening were its infectiousness and its lethality. Another ominous trait was that the new bug, whatever it might be, seemed so very good at riding on aeroplanes.

Hong Kong was merely the gateway for its international dispersal — but it was close to its origin.

The whole phenomenon had begun quietly, several months earlier, in the southernmost province of mainland China, Guangdong, a place of thriving commerce and distinctive culinary practices.

On November 16, 2002, a 46-year-old man from a city 80 miles northwest of Hong Kong came down with fever and respiratory distress. That he triggered a chain of other cases (his wife, an aunt, her husband and daughter) strongly suggests SARS was what he had. He has been described as a ‘local government official’, but the only salient aspect of his profile, in retrospect, is that he had helped prepare some meals, of which the ingredients included chicken, domestic cat and snake.

Snake on the menu wasn’t unusual in Guangdong. It’s a province of unsqueamish carnivores, where the list of animals considered delectable could be mistaken for the inventory of a pet shop or a zoo.

People wearing masks in the business district, Central, in Hong Kong, during the 2003 SARS outbreak

People wearing masks in the business district, Central, in Hong Kong, during the 2003 SARS outbreak

Three weeks later, in early December, a restaurant chef in Shenzhen, another sizeable Guangdong city, fell ill with similar symptoms.

Feeling sick, he commuted home to a hospital in another city, Heyuan, where he infected at least six healthcare workers before being transferred to Guangzhou, about 130 miles to the south-west.

Not long afterwards other such illnesses started occurring in Zhongshan, 60 miles south of Guangzhou. Within the next few weeks, 28 cases were recognised there. Symptoms included headache, high fever, chills, body aches, severe and persistent coughing, coughing up bloody phlegm and progressive destruction of the lungs, which tended to stiffen and fill with fluid, causing oxygen deprivation that in some cases led to organ failure and death.

Thirteen of the patients were healthcare workers and at least one was another chef, whose bill of fare included snakes, foxes, civets (smallish mammals, distantly related to mongooses) and rats.

Then a seafood wholesaler who had visited Zhongshan checked into a Guangzhou hospital and triggered the chain of infections that would circle the world.

This seafood merchant was Zhou Zuofeng. He became the first ‘superspreader’ of the SARS crisis.

A super-spreader is a patient who, for one reason or another, directly infects far more people than does the typical infected patient.

Chongqing, China, Asia - A female butcher is standing in front of a butcher shop that sells poultry

Chongqing, China, Asia – A female butcher is standing in front of a butcher shop that sells poultry

No one seems to know where Zhou picked up his infection.

He ran a shop in a major fish market, close to other live markets, including those that offered domestic and wild birds and mammals. The infection took hold, caused coughing and fever, and drove him to seek help at a Guangzhou hospital on January 30, 2003. In two days he infected at least 30 staff.

Zhou himself would eventually become known as the ‘Poison King’. He survived the illness, though many people who caught it from him — directly, or indirectly down a long chain of contacts — did not.

One of those secondary cases was physician Liu Jianlun, 64, a professor of nephrology at the teaching hospital where Zhou had first been treated. Professor Liu began feeling flu-like symptoms two weeks after his exposure to Zhou, and then seemed to get better — well enough, he thought, to follow through on plans to attend his nephew’s wedding in Hong Kong.

He and his wife took the three-hour bus ride from Guangzhou on February 21, crossed the border, spent an evening with family, and then checked into a large hotel called the Metropole, favoured by businessmen and tourists, in the Kowloon district. They were given room 911, across from the elevators in the middle of a long corridor, a fact that became central to later epidemiological investigations.

Two fateful things happened that night at the Metropole. The professor’s condition worsened; and at some point he seems to have sneezed, coughed, or (depending on which account you believe) vomited in the ninth-floor corridor.

In any case, he shed a sizeable dose of the pathogen that was making him sick — enough to infect at least 16 other guests and a visitor to the hotel. Professor Liu thereby became the second known super-spreader.

Among the hotel guests sharing floor nine was that 78-year-old grandmother from Canada. She had come to visit family and then spent several nights at the Metropole hotel, along with her husband.

Her room was 904, just across the corridor and a few steps down from Professor Liu’s. Her stay overlapped with his for only one night. Maybe they shared a ride in the elevator. Maybe they passed in the hallway. Maybe they never laid eyes on each other. No one knows.

What is known is that, the next day, the professor awoke feeling too sick to attend any wedding and instead checked himself into the nearest hospital. He would die on March 4.

One day after Professor Liu left the Metropole, the grandmother left, too. Infected but not yet symptomatic, and feeling fine, she boarded her flight home to Toronto — taking SARS global.

Apart from a few aftershock cases in early 2004, SARS hasn’t reappeared in humans . . . so far. But now something very much like it, the Wuhan coronavirus, is spreading across the world.

The scenario in 2003 could have been much worse. SARS was an outbreak, not a global pandemic. There were just over 8,000 cases, 774 died, not 7 million, as might have happened.

Several factors contributed to limiting the scope of the outbreak, of which good luck was only one. Another was the speed and excellence of the laboratory diagnostics — finding the virus and identifying it — by scientists around the world. And another was the brisk efficiency with which cases were isolated, contacts traced and quarantine measures instituted.

One further factor was inherent to the way SARS affects the body: symptoms tend to appear before, rather than after, a person becomes highly infectious.

That order of events allowed many SARS cases to be recognised, hospitalised, and placed in isolation before they hit their peak of infectivity. With flu and many other diseases the order is reversed, with high infectivity preceding symptoms by days: the danger, then the warning.

That probably helped account for the scale of worldwide misery and death during the 1918–1919 influenza [so-called Spanish flu] which killed an estimated 50 million: the bug travelled ahead of the sense of alarm. And that was before globalisation. Everything nowadays moves around the planet faster, including viruses.

When the Next Big One comes, we can guess, it will probably conform to the same perverse pattern, high infectivity preceding notable symptoms. That will help it to move through cities and airports like an angel of death.

Is the current coronavirus going to become such an event, such a global scourge, such an angel of death? Too soon to tell.

If it does, we needed to be ready for it yesterday. And if it doesn’t, the Next Big One is still coming, and we need to start getting ready for that one tomorrow.

Adapted from Spillover: Animal Infections And The Next Human Pandemic by David Quammen, published by Vintage at £12.99. © David Quammen 2012. Available from amazon.co.uk. 

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