April 15, 2020 / BY GAVIN YAMEY
Until we end COVID-19 transmission across the planet, we are likely to keep getting multiple COVID-19 “waves”— that is, rolling, recurrent outbreaks. While no public health expert has a foolproof crystal ball, this scenario of repeated waves means that the likely contours of the next one to two years are now coming into clearer view.
Right now, many countries including Italy, Spain, the United States, and the United Kingdom, are still struggling desperately to put out the initial fire. They are using suppression measures like stay-at-home orders as a fire extinguisher to smother transmission while urgently trying to ramp up their capacity to conduct testing, to manufacture and distribute personal protective equipment for health workers, and to treat people with COVID-19. 
Once countries have achieved a sharp fall in new daily cases, protected all their health workers, scaled up their hospital capacity to deal with future COVID-19 outbreaks, and can conduct widespread and efficient testing, isolation of cases, and contact tracing, they can then start relaxing their lockdowns.
But even in this best case scenario, we are likely to see further outbreaks, and we may need to turn on the fire extinguisher again.