SINGAPORE - In the ongoing battle to contain the spread of Covid-19, every measure will help to prevent its spread, from border controls to social distancing recommendations and even personal hygiene habits, experts said on Monday (March 23).
"Social distancing, personal hygiene, (and) business continuity plans can all help to reduce R0 (R-naught) to less than one," said infectious diseases expert Wang Linfa, during a panel discussion hosted by The Straits Times on the importance of personal hygiene amid the Covid-19 outbreak.
R0 refers to the basic reproduction number. It indicates the natural spread of the virus, said Professor Wang, who is director of the programme in emerging infectious diseases at Duke-NUS Medical School.
If R0 is less than one, it means each existing infection causes fewer than one new infection. In this case, the disease will decline and eventually die out, but if it is greater than one, it will probably keep spreading.
Countries, including Singapore, are taking measures to drive R0 to less than one, said Prof Want.
"I think so far we're doing pretty good, but I think we need to really keep it up," he said, adding that everyone, from the individual to the Government, could help to draw down R0 for Covid-19.
Prof Wang said the R0 for Covid-19 is estimated to be between two and three, similar to the severe acute respiratory syndrome (Sars). In comparison, the R0 for measles is about 12.
Prof Wang said bringing R0 down would also help to "flatten the epidemic curve" by preventing the number of infected cases from surging suddenly.
The epidemic curve is an n-shaped curve that is used to visualise when new cases happen and at what speed during a virus outbreak.
Said Prof Wang: "If you let the natural R0 play out, the hospitals will collapse because there's not enough beds, not enough ventilators. So the strategy is to flatten the curve so that, for example, you have severe cases of 10 per day rather than a hundred or a thousand per day."
Prof Wang was one of four panellists who took part in Monday's discussion.
The other three included Environment and Water Resources Minister Masagos Zulkifli, who is head of the new SG Clean task force; Mr Edward D'Silva, chairman of the Public Hygiene Council; and Mr Tai Ji Choong, director of the National Environment Agency's Department of Public Cleanliness.
While other measures - such as adhering to social distancing recommendations and staying home if one feels ill - are important, Mr Masagos said that it was also important for people to practise good cleanliness habits.
"Public hygiene, personal hygiene is our first defence. And it's not just our defence against Covid-19 today, but against other breakouts that we cannot foresee in future," he said.
Asked if travelling on public transport was safe, given the recent recommendations for people to keep their distance from others, Mr Masagos said the risk of exposure depended on a number of factors, including duration and intensity of exposure, and the density of the crowd.
Huge crowds, such as the religious gathering at a mosque in Malaysia, was one example of high-density situations that should be avoided, said Mr Masagos, who is also Minister-in-charge of Muslim Affairs.
"The other is intensity - how close are you to the person, how much you're interacting with the person," he said, citing the cluster of Covid-19 patients who were linked to a dinner event at Safra Jurong.
Contact-tracing efforts had found that the patients linked to the event had also spent time together outside the dinner, including going for karaoke sessions together.
Duration of exposure is also important, said Mr Masagos, adding that the rough guideline is to keep exposure to under about 30 minutes.
Said Mr Masagos: "Therefore, if in any social setting, if you can ensure that you have short duration, you have low intensity and you have low density, then you are safer than not."
Prof Wang added that in such an outbreak, there is no fail-safe measure and that there is a risk of exposure in any closed environment, including in an elevator.
However, he said: "But if you have to take public transport, the chance in Singapore of getting on a contaminated MRT, for example, is very low."
Said Prof Wang: "But even if the hand is contaminated, you're not going to be infected. It's only when you rub your nose or your eyes. You just need to be cautious that when you go out in public... Then as soon as you get to the office or home, wash your hands. I think that's the best you can do."