Here’s some good news for people residing in the United Kingdom. They are about to receive their first shots of a COVID-19 vaccine as early as this week, as US health officials continue to examine the proposed coronavirus vaccine.

However, vaccinating millions of people in the U.K. could pose enormous logistical challenges, such as keeping the doses frozen and figuring out how to fairly distribute the vaccine across the country of nearly 70 million.

The first lot of the vaccine, developed by Pfizer in association with German company BioNTech, arrived in the UK last week. Vaccine doses have been scheduled to be delivered to hospitals from today. Health workers, nursing home residents and employees, and older people will be the first in line to receive the vaccine.

According to BBC, 50 hospitals across England have been selected as hubs for vaccine administration. The UK government has initially ordered 40 million doses, which will vaccinate 20 million people, according to NPR.

The UK’s National Health Service (NHS) has said that more centers will be set up as more vaccines arrive.

Sarah Boseley of The Guardian said, “There’s something like five doses to each vial, and each box is 975 doses.” She has been writing about health and medical issues for the last 15 years for The Guardian.

“Because they’re kept in this deep-frozen state, they then have to be very, very carefully split up,” Boseley added. “And that is the bit, actually, that hasn’t yet been properly figured out.”

Why Americans are still waiting for approval from the Food and Drug Administration (FDA)? Boseley said, “The FDA in the United States actually demands all the raw details.”

UK drug regulatory bodies depend on companies’ summaries of their vaccine’s efficacy, while US agencies are more hands-on and warier.

“They’re not taking what the companies say as necessarily accurate,” Boseley explained. “So they will do their own data analysis and hopefully come up with exactly the same results.”

However, an FDA advisory panel is expected to meet virtually on Thursday to discuss whether to approve the Pfizer/BioNTech vaccine for emergency use. Also, the FDA will review Moderna’s COVID-19 vaccine on December 17.

Dr. James Hildreth, a member of the FDA’s vaccine advisory committee, told NBC last week, “We’ll spend the day on Thursday reviewing the data from Pfizer, and at the end of the day, a vote will be taken. So by the end of the day next Thursday, there could be a decision made about the vaccine.”

He added, “If the FDA commissioner decides to issue approval, the [emergency use authorization], on that day when the vote is taken, as early as Friday of next week, we could see vaccinations happening across the country.”

Once the FDA approved the vaccine, US military officials will help facilitate the distribution throughout the nation.

Apart from the UK, Bahrain has also approved Pfizer’s vaccine. The sovereign state in the Persian Gulf has become the second country in the world to issue an emergency approval of the vaccine. The new article was published on NPR.