A new study suggests that lifting all lockdowns two weeks after reporting no coronavirus cases can lead to a 97% risk of a second wave of COVID-19.

Here’s the scenario:

  • A country, city or town goes into lockdown because of the novel coronavirus, which has spread through the world and caused thousands of deaths. The country then lifts its lockdown two weeks later.
  • There’s a 97% risk of a second wave in that case, the study found.
  • The surge would likely happen 34 days after those controls are lifted. However, the risk drops down to 32% if some restrictions — like social distancing, face masks and quarantining close contacts — are kept in place. The rebound would happen in 42 days in that case, too.
  • The study was published in the journal Nature.


  • The research team used Wuhan, China — the city believed to be where the coronavirus outbreak began — to create a model where they explored how COVID-19 spread after lockdowns. The study examined how the virus spread through five different chunks of time. It accounted for transmission time, symptoms and more.

Why does this happen?

The researchers said there were two reasons the virus spread again — those who are asymptomatic passing on the virus, and how easily the virus can pass from one person to another, according to Newsweek.