How contagious is the ‘mutant’ UK COVID strain? Let the data tell us

In his most recent book Talking to Strangers, Malcolm Gladwell discussed the concept of a “default to truth” — i.e. our fundamental reaction to the receipt of new information is to believe it. We assume that people (especially those in positions of authority) are generally honest.

We have witnessed a default to truth surrounding the B.1.1.7 strain of COVID-19, often referred to as the UK mutant strain. Journalists, politicians and even chief medical officers have breathlessly warned about it. Last week Brisbane and surrounds areas were locked down for three days due to a single case, and the federal government abruptly halved the quota of returning residents.

It has been widely reported that the mutant strain, announced on December 14, is up to 70% more infectious than earlier strains. Western Australian Premier Mark McGowan confidently claimed: “This is the British strain which is highly contagious and obviously causing mass deaths.” Queensland Premier Annastasia Palaszczuk warned: “This highly contagious UK variant … is a new ball game.”