Measles Cases Bring Temporary Halt to Afghans’ Arrival in U.S.

The C.D.C. asked that the evacuation flights from overseas bases be suspended after four Afghans were found to be infected.

Federal Research Bolsters the Case for Vaccine Mandates

Scientists believe the administration’s new measures may tamp down the pandemic, although the effects will not immediately be obvious.

Opinion | Biden’s Vaccine Mandate Is a Big Mistake

Vaccines work. But a mandate by the federal executive is an overreach that may backfire.

When Was the First U.S. Covid Death? C.D.C. Investigates 4 Early Cases

The deaths, spread out across four states in January 2020, have become part of a scattershot collection of clues about the virus’s early spread.

Health Officials Advise White House to Scale Back Booster Plan for Now

Federal regulators warned on Thursday they may not have enough data to recommend boosters for anyone except certain recipients of the Pfizer vaccine by late September.

Hospitalizations for children sharply increase as Delta surges, C.D.C. studies find.

Vaccinations, however, have made a difference.

Health Officials Advise White House to Scale Back Booster Plan for Now

Federal regulators warned on Thursday they may not have enough data to recommend boosters for anyone except certain recipients of the Pfizer vaccine by late September.

Unvaccinated Americans should avoid Labor Day travel, the C.D.C. director says.

With the Delta variant spreading and cases, hospitalizations and deaths rising, Dr. Rochelle P. Walensky is urging caution.

Teachers, Police, Other Public Workers Left Out of Mental Health Coverage

Health plans for state and local workers can opt out of the federal law requiring them to treat mental health like other medical conditions.

La variante delta se infiltró en un aula de primaria. Así sucedió

Un detallado estudio realizado en California descubrió que la variante se propagó fácilmente de una profesora no vacunada a los niños y, en algunos casos, a sus familias.

How the Delta Variant Infiltrated an Elementary School Classroom

A detailed study in California found that the variant easily spread from an unvaccinated teacher to children and, in a few cases, their families.

Biden Floats Faster Access to Booster Shots Amid Spread of Variant

The White House played down the president’s remarks, saying the administration had not changed its original proposal to administer a third shot to most vaccinated adults eight months after the second.

Some Hotels Are Mandating Vaccines. Will Others Follow?

Following the lead of accommodations abroad, some U.S. hotels are starting to require proof of vaccination for guests and staff.

Opinion | Show Me the Data!

A lack of systematic evidence has kept scientists one step behind in the pandemic.

Supreme Court Ends Biden’s Eviction Moratorium

The ruling followed political and legal maneuvering by the administration to retain protections for tenants. It puts hundreds of thousands at risk of being put out of their homes.

Supreme Court Ends Biden’s Eviction Moratorium

The ruling followed political and legal maneuvering by the administration to retain protections for tenants. It puts hundreds of thousands at risk of being put out of their homes.

Who Can Make You Get a Covid Vaccine?

Employers, universities and local governments can all issue some type of vaccination requirement. Here’s what to know about the mandates.

Hurricanes Get Names. What About Heat Waves?

Short, distinctive names are assigned to storms to raise awareness about their dangers. Some experts argue for doing the same for heat waves, which can be even deadlier.

Cruise Passenger Dies From Covid, Testing Industry Plans

The passenger and 26 crew members aboard the Carnival Vista tested positive for the coronavirus and the passenger later died. The company says its protocols successfully stopped further spread.

The U.S. Is Getting a Crash Course in Scientific Uncertainty

As the pandemic takes an unexpected direction, Americans again must reckon with twists in scientific understanding of the virus.