By PHILIP MARCELO, ANNE D'INNOCENZIO and BOBBY CAINA CALVAN Associated Press

BOSTON (AP) — The surge in coronavirus cases driven by the new omicron variant is the latest blow to hospitals, police departments, supermarkets and other critical operations struggling to maintain staffing levels.

COVID-19 absences among workers at London hospitals tripled this month, and nearly 10% of the city's firefighters were out sick.  In New York, about twice as many police officers took sick time this week than normal.  Countries such as Spain have eased quarantine rules to allow more people to continue working.

Some U.S. states have called in the National Guard to help boost short-handed hospitals.

Answers to 25 common COVID-19 vaccine questions

Vaccinations for COVID-19 began being administered in the U.S. on Dec. 14, 2020. The quick rollout came a little more than a year after the virus was first identified in November 2019. The impressive speed with which vaccines were developed has also left a lot of people with a lot of questions. The questions range from the practical—how will I get vaccinated?—to the scientific—how do these vaccines even work?

Keep reading to discover answers to 25 common COVID-19 vaccine questions.

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