Cramped workplaces, parties … the factors fuelling local Covid-19 spikes

What have resurgences around the world taught us about how local clusters emerge?

It is not always possible to pinpoint the origin of a local spike in cases, particularly in countries like the UK, where the disease is still circulating at relatively significant levels.

But in countries where overall caseloads are lower, and with rigorous test-and-trace schemes, it has been possible to pinpoint the factors that have sparked or fuelled local outbreaks.