Fighting virus spread indoors with help of previous work

At the start of the Covid-19 outbreak, healthcare professionals and policymakers were stumped on many fronts. A key question was how the coronavirus had spread from human to human.

Researchers like National University of Singapore (NUS) Associate Professor Tham Kwok Wai leapt into action, tapping their previous work.

Prof Tham, who had researched the spread of viruses such as influenza in an indoor setting, found that the indoor environment was also a primary domain for transmission of the virus that causes Covid-19.

Because of his previous research, he knew there were measures that could control its spread indoors. For instance, increasing ventilation of a room will help to dilute the concentration of the virus in the air, reducing transmission risk. Safe distancing also works, as the viral load diminishes with distance from the infected person, he said.

Passing re-circulating air through high efficiency filters can help to remove viruses that usually "clump" together, said the professor from the NUS School of Design and Environment.

Before Covid-19, Prof Tham's research had focused on the impact of the indoor environment on humans, and on cooling and ventilation technologies for indoor environmental control.

"I began to see how I could apply my research on environmental intervention to Covid-19 at the onset of the pandemic, around December 2019," he said.

Prof Tham said tackling the outbreak requires researchers with various expertise.

Other than virology, for instance, knowledge in aerosol science or fluid mechanics could also help with better understanding of how expelled droplets could spread.

Prof Tham said: "This demonstrates how a trans-disciplinary approach is essential in tackling the Covid-19 challenge holistically. And this constitutes the basis for policy formulation."