In Focus: Three decades, three coronaviruses

While humans have been plagued by coronavirus-induced coughs and colds (which account for about a quarter of all coughs and colds), this family of viruses has long been overshadowed by its more lethal rivals—Ebola, Nipah and even Influenza. Coronaviruses, which posed little immediate danger to human health, were largely left uninvestigated. 

That changed with the eruption of Severe Acute Respiratory Syndrome or SARS in 2002, which infected 8,098 people and killed 774 worldwide. A decade later, another coronavirus, Middle East Respiratory Syndrome or MERS, hogged the spotlight. With a death rate of more than 35 per cent, it remains the deadliest coronavirus to hit humanity. 

When this novel coronavirus, called coronavirus disease-2019 or COVID-19, erupted with the start of a new decade, it had the appearance of SARS. It is this similarity that has dictated containment efforts so far. Among these measures were early detection, isolation of infected individuals, rigorous contact tracing and quarantine. Social distancing also played a key role in a community containment strategy. 

But there are differences between the two viruses. COVID-19 appears to be less deadly than either SARS or MERS, killing up to five per cent of infected individuals in the worst affected area. At the same time, it has spread much faster. 

“It will be the extent of these differences that will determine whether we can contain the novel coronavirus with the same measures,” said LKCMedicine Visiting Professor Annelies Wilder-Smith. 

“If these measures fail, we will need a vaccine to contain this epidemic,” she added.

The race is now on to develop antibody therapies and vaccines that could protect people from developing severe disease. A novel antiviral and HIV drugs are already being used in clinical trials in China, while experts predict that the first vaccine trial could start as early as April. And scientists in Singapore are pushing to be part of the vaccine study that will be led by the Coalition for Epidemic Preparedness Innovations. However, any successful vaccine will likely be too late to mitigate the current outbreak.

The scientific world could have been better prepared for another coronavirus outbreak, believes LKCMedicine Associate Professor of Infection & Immunity Luo Dahai.

“I would bet that if we'd managed to get an antiviral against SARS coupled with ongoing research, those drugs would most likely be good for this,” he said. However, by the mid- to late-2000s, funding for SARS-related research had become very limited.