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Can America Handle a Second Wave?

The United States is not limiting COVID-19 infections enough to avoid a serious second wave of the pandemic later this year. As communities reopen and behavior patterns loosen still further, the country will be forced to face the consequences of its insufficient action to date.

CAMBRIDGE – Like surfers looking out for the next big breaker before the first one has passed, epidemiologists and public-health officials in the United States are bracing themselves for a fresh surge of COVID-19 infections later this year. The fear is that this second wave will coincide with the peak of the 2020-21 US influenza season, triggering a new flood of hospital patients in dire need of respiratory support.

The fear is justified, based on what we know about coronaviruses and influenza. For both, infections begin rising in November and peak at some point in December, January, or February, before subsiding by April.

What is less certain is how high the waves for each infection will be. Although we understand influenza infection patterns much better than that of the SARS-CoV-2 virus that causes COVID-19, influenza remains a known unknown. Its strains vary from year to year in terms of both transmissibility and severity. In some years, the number of lives lost to influenza in the US can be as low as 12,000. But during the 2017-18 winter, a particularly lethal strain led to the death of an estimated 80,000 Americans – the highest such toll in at least 40 years.