At least 1,008,025 Americans had received their first dose of the vaccine as of 9 a.m. Wednesday, according to a tally from the Centers for Disease Control and Prevention.

There have been 9,465,725 doses distributed across the country.

ABC News’ Eric Strauss contributed to this report.

The first New York City EMTs were vaccinated Wednesday morning, with the hopes of inoculating 450 FDNY members per day.

Since the pandemic began -- with New York City as the spring’s epicenter -- 5,700 members of the FDNY have been diagnosed with COVID-19.

On Tuesday, the FDNY lost its 12th employee to COVID-19. EMT Evelyn Ford, 58, leaves behind four children.

ABC News’ Aaron Katersky contributed to this report.

In the wake of new variants of the coronavirus in the United Kingdom, travelers arriving in New York City from the U.K. will be visited by a sheriff’s deputy to confirm they are quarantining, Mayor Bill de Blasio said.

Additionally, all international travelers will receive a city health commissioner’s order to quarantine via certified mail.

Those who are found in violation will face daily $1,000 fines.

“We cannot take chances with anyone who travels,” the mayor said.

ABC News’ Aaron Katersky contributed to this report.

Another COVID-19 variant has been detected in two cases in the United Kingdom, Health Secretary Matt Hancock said.

"Both are contacts of cases who have traveled from South Africa over the past few weeks,” Hancock said.

Hancock said the “new variant is highly concerning because it is yet more transmissible and it appears to have mutated further than the new variant that has been discovered in the U.K."

The health secretary said both cases and close contacts of the cases have been quarantined.

U.K. travel to and from South Africa is suspended, Hancock said.

The coronavirus is constantly mutating, and there are many thousands of lineages of the virus, each with distinct mutations. There's no evidence this new variant is more deadly and there's no evidence it will affect the vaccine.

ABC News' Mike Trew contributed to this report.

The Centers for Disease Control and Prevention will now require a negative COVID-19 test for all air travelers coming to the United States from the United Kingdom in the wake of news about new strains of the virus being detected in the U.K.

Everyone arriving in the U.S. must have a negative PCR or antigen test from within 72 hours of departure, according to a statement from the CDC.

"The public health authorities in the United Kingdom recently announced the discovery of a new variant of SARS-CoV-2," the CDC wrote in its announcement. "Viruses constantly change through mutation, and preliminary analysis in the U.K. suggests that this new variant may be up to 70% more transmissible than previously circulating variants."

Passengers will have to provide written documentation of the negative test and airlines will be required to confirm the information, the CDC said. Airlines will have to refuse anyone without a negative test.

While the strain appears to be more transmissible, there's no evidence it is more deadly, or that the vaccines currently being rolled out won't be effective against it.

President Donald Trump, who is spending the Christmas holiday in Florida, will sign the executive order on Friday and it will go into effect on Monday.

Dozens of countries have largely banned travelers from the U.K., at least temporarily, including Canada, Mexico, Russia, China and India. The U.S. is one of a handful of countries that will require negative tests, including Greece and Spain.