THE VIRUS DETECTIVES

FIONA MCMILLAN reports from frontline genomic, virology, pharmacology and immunology research as the world chases solutions to the COVID-19 pandemic.

impeachment in the US and Brexit competing for the world’s attention, the mystery virus only garnered modest interest.

For those who know viruses, however, something wasn’t quite right. By early January, official reports announced no evidence of significant human-tohuman transmission. Yet, by 1 January there were already 40 confirmed patients, and 59 by the 9th. Even in the confines of a crowded marketplace, this seemed high for all the cases to have emerged from contact with the same animal. Then there were the symptoms: a fierce fever coupled with the onset of a persistent dry cough and breathlessness, and rapid progression to pneumonia. Bacteria were ruled out – it wasn’t a new superbug. Influenza was also eliminated – this wasn’t bird flu. Soon, staff in Wuhan’s major hospitals were trying to raise the alarm: this illness looked a lot like SARS.

In 2003, Severe Acute Respiratory Syndrome spread through China’s Guangdong Province. By the time it had run its course it had reached 26 countries and infected more than 8000 people; 774 had died.

The SARS virus (SARS-COV) was a coronavirus, which most likely crossed the species barrier from bats. Coronaviruses are common in the animal kingdom, but historically they haven’t caused humans much bother. In fact, until 2003 only four strains were circulating in the human population; all tended to cause only mild common-cold symptoms. But in many of those infected, SARS-COV caused severe disease, including extensive damage to lungs and other organs. In 2012 another coronavirus – Middle East Respiratory Syndrome (MERS)

2019-12-25 Ren et al China

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Male Wuhan

Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College