On Feb. 21, 2003, a doctor from Guangzhou, China, visited Hong Kong to attend a wedding of a relative. After having flu-like symptoms for a few days, the doctor suddenly got worse at a hotel in Hong Kong. He would have had a severe cough in the hallway or the elevator, as well as in room 911 on the ninth floor of the hotel that he stayed with his wife.
|Kang Yang-gu, Knowledge curator|
Five days later, on Feb. 26, a businessman collapsed due to a mysterious illness in Hanoi, Vietnam. On March 1, a flight attendant died in Singapore. Three days later, a 78-year-old woman died in Toronto, Canada, for an unknown reason. The nine people around the world, who stayed on the same floor of the hotel with the doctor, collapsed without a known cause.
Almost as soon as the 21st century began, the tragedy of the SARS (Severe Acute Respiratory Syndrome) pandemic began. During about nine months of the global outbreak, 8,273 people contracted the disease and 775 died. What does this recollection of what happened 17 years ago mean to us when a new coronavirus outbreak threatens China and the world? The SARS outbreak was a prelude to the current situation because of the three reasons.
First, it was an infectious disease transmitted from animal to human.
Based on the onset, SARS broke in 2002, swine flu in 2009, MERS (Middle East Respiratory Syndrome) in 2012, and the new coronavirus in 2019. All of these infections had animal-borne pathogens. Viruses that had lived in bats, pigs, and camels moved to a human at some point.
It was predictable enough. Animals that have been a host for viruses for a long time are no longer an excellent host. As we can see from the destruction of the rainforest, the destruction of the ecosystem continues to reduce habitats, resulting in a noticeable decline in animal populations. For example, only 4 percent of all mammals, except for humans, are in wildlife. The rest, such as cattle and pigs, are domesticated. Chickens and ducks make up 70 percent of all birds.
Climate change worsens this problem. Animals, which have adapted to the cold Earth for a long time, will find it difficult to withstand global warming. Before industrialization, the surface temperature of the globe used to be at 14 degrees Celcius. The global average temperature has risen by 1 degree now. At this moment, many animals are disappearing without any trace.
Viruses that have been dependent on animals for a long time must adapt to these changes. For viruses that cannot survive without hosts, humans, cows, pigs, and chickens are very attractive. The population is large, and they live in one place, so once viruses settle, they don’t have any reason to move to others. SARS, swine flu, MERS, and the new coronavirus are the result of the adaptation of viruses.
Second, the virus travels by airplanes.
In a hotel in Hong Kong in 2002, the SARS virus settled in many people from around the world. The virus then flew to Hanoi, Singapore, and Toronto in a few days. One 46-year-old Filipino woman who worked as a caregiver was one of several people that the virus targeted in Toronto. As she visited her hometown in the Philippines, the virus traveled the Earth in just six weeks.
Viruses attempted to invade a new host, a human, numerous times in the past. However, half of the attempts were a failure because viruses had to go through several mutations to infect a human, and the impact was limited. Such virus infection affected only several people at a small and remote village in Southeast Asia or Africa.
However, as the globe got closer by ships, trains and airplanes, viruses had a new opportunity. As with the case of the SARS outbreak, it has become possible for viruses to travel this globe in six weeks by transferring the airplane many times. As long as viruses are connected to a proper host who can take them on a flight, the mutated virus can cause a pandemic almost instantly.
The MERS virus used to be confined to the Middle East in the past, but it could take a heavy toll on Korea in 2015 because the virus moved on a flight. In 2020, the new coronavirus settled in Wuhan, which populates more than 10 million, and is spreading around the globe by trains or airplanes.
Third, there was human greed.
At this point, I should mention another reason why the distance between humans and animals has become so close in the 21st century. Guangdong, where SARS originated, is famous for unusual wildlife dishes. However, such unusual wildlife cuisine is not a tradition of long history but a result of the “propensity for conspicuous consumption” that appeared with the expansion of the Chinese economy.
The rich people’s desire to try something different from ordinary meals has generated and expanded a new industry for hunting, breeding, and circulating wild animals. Wild animals that used to live in caves and swamps in rainforests were raised outside the city, and many were trapped in cages in the market.
Within these wild animals, numerous viruses kept mutating to take them as a new host. It is the same case with the new coronavirus. The human greed trying to swap money for “a taste of wild” sparked the new coronavirus to spread in a crowded market in Wuhan.
The SARS took 775 lives, but we were lucky 17 years ago. Despite the jaw-dropping power of transmission and the high fatality at around 10 percent, the SARS virus decreased in nine months. What about the novel coronavirus? Will we be lucky this time, too? What about next? A stronger virus will attack us if those three points are combined. I’m sure humans will run out of luck.
This column was originally published in Korean in Changbi Weekly Commentary. – Ed.
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