On 21 February 2003, a physician in Hong Kong was feeling particularly unwell. He must have had an inkling that something serious was amiss, for his symptoms closely matched those of a number of patients he had treated in recent weeks: fever, aching muscles, headache, a dry cough, and shortness of breath. An alarmingly high proportion of these people had become critically ill, with inflamed, fluid-saturated lungs. Breathing was rendered somewhat difficult, and death frequently followed.

Although the sixty-four year old nephrologist resided in the Guangdong region of southern China, he was enjoying time away for a family wedding when the worst of the symptoms struck. Sketchy reports of a mysterious respiratory illness had been filtering out of his home province for several months, but the official channels gave no indication of anything untoward. The day he arrived in Hong Kong he felt well enough to check into his room on the ninth floor of the Metropole Hotel, and he even did some sightseeing and shopping later in the afternoon. But the following morning his condition had worsened, and he was forced to seek care at the territory’s Kwong Wah Hospital. There he told staff he feared he had contracted “a very virulent disease,” and suggested immediate isolation. Yet the damage had already been done.

Back at the Metropole Hotel, globetrotting guests from the ninth floor were preparing to leave for Canada, Singapore, and Vietnam. Soon, they too would fall ill. In less than a week, the world would be left poised on the brink of a pandemic. Severe Acute Respiratory Syndrome (SARS) had arrived. While the occupants of the western hemisphere often remember the events in the context of an overblown media frenzy, many epidemiologists today regard the outbreak as a near-miss for humanity⁠— one which might have become one of history’s most unpleasant epidemics had it not been for the quick thinking and selflessness of a few individuals.

Dr Carlo Urbani
Dr Carlo Urbani

In early 2003, the first unfortunates infected outside of Guangdong began to seek medical attention. At this stage there seemed to be little cause for alarm. Respiratory disease is common in Southeast Asia, and although the rumours coming out of southern China had instilled a heightened sense of readiness, nobody knew exactly what to expect. Owing to the speed of modern air travel and the disease’s incubation period of up to ten days, the individuals who had come into contact with the index case at the Metropole Hotel became unwittingly efficient vehicles for the newfangled virus. The next few days would be crucial.

On 26 February, a businessman named Johnny Chen was admitted to The French Hospital in Hanoi, Vietnam suffering from a respiratory illness. As his condition rapidly deteriorated, the staff sought the assistance of Dr Carlo Urbani, an Italian epidemiologist who was working with the local World Health Organization (WHO) office. Vietnamese doctors feared a human case of avian H5N1 influenza, or ‘bird flu’, and were keen to involve the WHO at an early stage. Donning a mask– unfortunately the hospital lacked goggles and other protective clothing– Dr Urbani examined the patient. There was no history of fowl interaction, so bird flu seemed unlikely. Two days later, hospital workers began to suffer from fever and dry cough. While the disease was clearly infectious, extensive tests failed to reveal any known pathogen.

The esteemed Dr Urbani gave his considered opinion: this was serious. The worried Vietnamese authorities concurred, and locked down the entire hospital. The hospital staff isolated all patients and employees who showed symptoms, placed the premises under guard, and garbed all yet-to-be-infected hospital workers with proper protective clothing. Over the next week Dr Urbani visited the hospital on a daily basis, helping the staff to maintain morale while introducing basic infection control procedures. Urbani quickly recognised that they were dealing with something unusual, and persuaded the Vietnamese government to allow outside help. He alerted WHO’s Geneva headquarters on the 05 March, and shortly Hanoi became host to numerous international experts, including a team from the US Centers for Disease Control (CDC).

After two weeks attempting to master the mysterious disease, Dr Urbani was exhausted. Eventually his wife and superiors persuaded him to take a break, and he decided to travel to Thailand, where he was scheduled to present a lecture at a medical conference. On 11 March, as his plane flew high above the dense jungle of Indochina, Dr Urbani developed a headache. Soon he spiked a fever and began coughing. Upon landing, he was met by a CDC colleague. Dr Urbani was quite aware of his symptoms’ likely cause, so warned his friend not to approach, and called for an ambulance. For some time the two men sat in silence, facing each other across a hopefully-safe distance while the paramedics assembled their protective gear. One thing was certain: the Bangkok medical conference would be missing a speaker that year.

Elsewhere the virulent disease continued its global migration. Forewarned by Dr Urbani and events in Vietnam, workers from the WHO were quick to connect the mushrooming reports of respiratory illness in Southeast Asia and beyond. On 12 March, for the first time in its fifty year history, the organization issued a Global Alert. Two days later, the gravity of the outbreak was underscored by the death of Johnny Chen, one of the microorganism’s first high-profile victims. SARS was formally named and defined, and a strategy of screening, isolation, and quarantine was recommended. Meanwhile, a worldwide network of laboratories was set up to identify the cause of the illness. Beakers and vials of various bodily fluids were shuffled around the globe for analysis. As part of this effort, the world saw the first widespread and coordinated deployment of 21st century information technologies in the battle against epidemic disease: international experts used a dedicated secure website to share information, and made extensive use of teleconferencing facilities to communicate. Virtually every weapon in mankind’s medical armoury was deployed against the emerging threat.

By the end of March, a hitherto unknown type of coronavirus was identified as the probable SARS pathogen. In an unprecedented two weeks, a Canadian team managed to sequence the virus’ entire DNA code. With this vital information, work could begin on developing diagnostic tests, treatments, and vaccines for the deadly disease. Nonetheless the rate of new infections continued to increase. The mortality rate of the disease approached 10%, much higher than that of common respiratory conditions such as seasonal influenza, and higher even than the mortality rate of the deadly 1918 “Spanish Flu” pandemic. Anybody– young or old– in close contact with an infected person was at risk of contracting SARS, including hospital staff members. An outbreak in Hong Kong’s Amoy Gardens signalled that the disease was becoming endemic in the general population, indicating to epidemiologists that SARS was probably here to stay.

Soon the international media itself developed a headache-inducing fever. Anxious news reports braced the world for an orgy of wholesale death and disability. Some near-panicked citizens started wearing medical face masks, erroneously believing that the virus was readily transmitted in the outside air. The cost of masks doubled across the Far East, while in Taiwan, supply shortages prompted villagers to strap bras across their faces to guard against the fearful SARS germ. In the absence of any official information and guidance, confused Chinese citizens bought up vinegar and other ineffective folk remedies on a massive scale.

As epidemiologists redoubled their efforts to contain the disease, it became apparent that an important link was missing. As early as December 2002, the WHO had requested information from the Chinese authorities regarding the mysterious Guangdong disease. China’s response was spectacularly sparse. As the crisis unfolded, China was quick to assume a leadership role in crisis-denial. They consistently under-reported the number of cases, they withheld information from international health organizations and from the Chinese people, and their official pronouncements ranged from highly misleading to laughably over-optimistic. Although a WHO team eventually gained access to the country, the Chinese government severely restricted their movements. When the disease reached Beijing and began to spread through military hospitals, the international experts were helpless to assist. Chinese doctors treating SARS cases in the city were sworn to silence, aware that their career, freedom, and personal safety were at stake.

Beijing's Forbidden City
Beijing's Forbidden City

In early April, however, a 71 year-old doctor named Jiang Yanyong began to speak out against the official policy. Unlike most Chinese dissenters, Dr Jiang openly identified himself, and made no secret of his role as a senior military doctor in the People’s Liberation Army, and a lifelong member of the Communist Party. Perhaps he owed his doggedness to his advancing years; while he understood the authorities’ efforts to maintain prestige and public order, he was convinced that the free flow of information would be needed to halt the spread of the disease. If SARS were to rampage unchecked among the 1.3 billion Chinese population, the best disease-control efforts of other countries would be in vain.

Regardless of the great personal risk, Dr Jiang dispatched a concerned email to two TV stations in Hong Kong. Soon his writings were in the hands of the international press, including a translation in Time magazine which exposed China’s information-tweaking hijinks to the English-speaking world. Not long afterwards, he openly criticized his superiors at an international press conference. Dr Jiang’s gambit successfully stirred up widespread international outcry. The world’s attention insulated him from repercussions, and his government was forced to acknowledge the true extent of the SARS problem and develop effective public health programs. The WHO team was permitted full access to study the disease in Guangdong, the mayor of Beijing and the Health Minister were sacked, and the authorities issued a rare public apology.

With the establishment of effective infection controls, the tide started to turn. By the end of May 2003, the rate of new cases began to fall worldwide, and by June they slowed to a trickle. By July, two hundred patients remained in various hospitals across the world but no new infections were being reported. Over the next few weeks the remaining patients either recovered or died. Suddenly– almost as quickly as it had appeared– SARS was gone.

Coronavirus
Coronavirus

Ultimately the disease infected over eight thousand people, and caused nearly eight hundred deaths. While these few hundred fatalities pale in comparison to the millions of deaths caused every year by familiar killers such as malaria and HIV, the importance of the SARS story goes far beyond a simple body count. Many troubling scientific questions remain unanswered, such as why and how the SARS virus triggered Acute Respiratory Distress Syndrome in many patients. It is believed that the Spanish flu virus caused a similar inflammatory response, thereby killing about 40 million people worldwide between 1918 and 1920. Another mystery concerns the origin of the SARS coronavirus. One possible animal source has been identified as the civet cat– a small forest-dwelling mammal confined to Southeast Asia and eaten as a delicacy by some people in southern China– but later an almost-identical virus was found in the horseshoe bat, a species found throughout Europe and Asia. How the disease jumped between these species, and onwards into humans, remains unclear. The solving of such conundrums would signal a new level in our understanding of epidemic disease as a whole, not just of SARS.

In public health circles, the SARS outbreak remains a vitally important case study for how to respond to emerging infections. International epidemiologists pore over the lessons from the near-pandemic, and consider how best to use them in anticipated outbreaks of bird flu, or other inevitable plagues of the future. But apart from one blip in 2004–related to an accidental laboratory spillage– SARS seems to have totally disappeared as a human disease.

For the general public, it’s difficult to know what to make of the SARS story. The public perception is polluted by images of isolation-suited medics, mask-wearing city-dwellers, and unearthly infrared figures in airport thermal scanners. Then, as now, it was easy to dismiss it all as “media hype.” But victory in the battle against SARS was never a given. Prompt action by doctors and public health officials kept fatalities down, and the timely interventions of a few key people were crucial in preventing a probable pandemic that could have killed many thousands⁠— if not millions⁠— of people worldwide. Though some individuals such as Dr Jiang managed to weather the skirmish unscathed, Dr Urbani was not so fortunate. On 29 March 2003, the eminent epidemiologist succumbed to the SARS virus in a makeshift isolation room in a Thai hospital a long way from home. Let us not forget the efforts of Drs Jiang, Urbani, and the other heroes of SARS. Some paid a high price indeed.