Mayor Bill de Blasio has announced a vaccine mandate for all private employers in New York City that will cover customers and employees over 12 years old, starting Dec. 27.

The move is a first in the country, intended as a “pre-emptive strike” against the spread of the omicron coronavirus variant.

Epidemiologists say the concern is warranted — but Baylor University’s Dr. Peter Hotez reminds Americans that while omicron merits study and caution, we can’t forget about the delta variant, which could help create a twin pandemic this winter.

This article was originally published on WBUR.org.

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