As we are seeing the beginning of the end of the first wave of COVID-19, the burning question is – will there be a second wave? No one knows, and there are both reasons for hope and caution. One sobering fact – the last 14 flu pandemics all had a second wave or multiple waves. SARS-CoV-2 is not the flu, but it is a respiratory virus and spread may be similar. This may also be a function of the dynamics of pandemics more than the characteristics of a specific virus.
A 2013 study modeling the most recent flu pandemics also found they all had at least a second wave. However their models also found that if measures were taken to reduce the number of infections in the first wave, and to “flatten the curve”, this could prevent a second wave. The COVID-19 pandemic is unique in recent history due to the extreme lengths we have all gone to flatten the curve. Perhaps our efforts, if we sustain them long enough, will prevent a second wave. That’s quite an incentive.
Have those efforts actually worked? The evidence suggests the answer is a huge – yes. A recent study published in Nature found:
We estimate that across these six countries (China, South Korea, Italy, Iran, France, and the United States), interventions prevented or delayed on the order of 62 million confirmed cases, corresponding to averting roughly 530 million total infections.