The head of the World Health Organization cautioned those who have been vaccinated against complacency as coronavirus cases surged in Europe and rose in large swaths of the United States.

On the eve of Thanksgiving, WHO Director General Tedros Adhanom Ghebreyesus lamented “the false sense of security that vaccines have ended the pandemic.” Tedros urged everyone — including the vaccinated — to continue wearing masks, maintaining distance and avoiding crowds, citing the “unsustainable pressure” on health systems in many countries.

In the United States, new daily coronavirus cases have risen by 10 percent in the past week, according to Washington Post figures. Deaths have increased by 10 percent, while hospitalizations have inched up by 4 percent in that period.

More than 36 million Americans have received their booster shots, according to the Centers for Disease Control and Prevention. Almost 60 percent of people in the country have been fully vaccinated.

Here’s what to know

  • With Thanksgiving around the corner, Americans are asking how to handle holiday visits to unvaccinated households and how to safely travel across the country.
  • Anthony S. Fauci, the top federal infectious-disease expert, said in an interview with Reuters that the “overwhelming majority” of vaccinated Americans should receive a booster dose.
  • The World Health Organization has warned that covid-19 deaths in the European region are projected to reach 2.2 million by next spring, based on current trends. Europe has become the epicenter of the pandemic, with death rates on the rise, especially in pockets where vaccination rates remain low.