k and control of the epidemic
A low value of k, as there is with coronavirus, can be seen as an advantage when trying to control an epidemic. As a small number of people – the super-spreaders – cause most of the new cases, the epidemic can be controlled by focussing on reducing the chances for them to transmit the virus. But what makes a super-spreader?
Becoming a super-spreader depends on being highly infectious, but people also become super-spreaders because of what they do. As we all learn more about coronavirus, we have learned that there are certain activities we should avoid if we want to avoid exposure to the virus. These include spending long periods of time in close contact with other people, indoors in poorly ventilated areas, and being among other people who are singing or shouting. These activities can easily become super-spreader events, if someone in the group has coronavirus.
The challenge with coronavirus is that people who have it are infectious before they have symptoms of the disease, when they are still asymptomatic. People can therefore become a super-spreader before they even know they are unwell. This means that, when there are a lot of people in a community who have coronavirus, we all need to avoid the sorts of activities which could lead to super-spreading, not just those who feel unwell.