How exactly the new coronavirus spreads – through airborne respiratory droplets, touching infected surfaces, and more – is still unknown. But what does seem to be known is that spread is inconsistent – meaning that some people spread it while others – most others, in fact, don’t spread the virus.
According to data in Ars Technica, as little as 10 to 20 percent of people infected with this coronavirus may be responsible for 80 percent of its transmission. On the other hand, 70 percent or more of infected people may not pass the virus to anyone.
The key is identifying superspreaders. But it’s almost impossible to identify which people are superspreaders. But we can identify events that pose a risk of large-scale transmission.
Superspreading events tend to occur in specific settings — large social gatherings, busy nightclubs, and crammed workplaces, places where one contagious person can spread it to many others quickly.
Japan has been relatively successful managing the pandemic, implementing a policy called the three Cs: Avoid Closed spaces with poor ventilation, Crowded places, and Close-contact settings, such as close-range conversations. The risk for superspreading is highest in situations with all three Cs.
Look at Hong Kong. Superspreading played a huge role in transmission there, with large clusters of cases linked to bars, weddings, temples, work and dinner parties. Just 20 percent of Hong Kong’s cases were responsible for 80 percent of transmission.
Likewise, in Shenzhen, China and in London, about 10 percent of cases account for 80 percent of transmission.
Who is a so-called superspreader of COVID-19, and why they are so infectious, are still unknown. But if we can stop superspreading events, we might largely halt the pandemic.