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The essential COVID-19 vaccine FAQ

The largest vaccination campaign in United States history has begun protecting its first recipients against the novel coronavirus. Yet there are a number of logistics to be mapped out and questions answered before the country can regain control over COVID-19 and restore a semblance of normal life.

This pandemic marks new territory for the governmental regulators, public health officials and private companies working to deploy a safe vaccine to the public — and also design public health campaigns to promote awareness and ease concerns. Potentially viable vaccine candidates have been produced in record speed — months, not years — including some by new technology. The Food and Drug Administration and the Centers for Disease Control and Prevention are currently working to figure out what is safe for approval, and how to immunize the population effectively.

Several polls suggest that roughly half of Americans are hesitant about getting vaccinated for COVID-19 — a significant drop compared to earlier during the pandemic. That’s problematic since more than 60 percent of people may need to be inoculated to develop widespread immunity.

As the U.S. is seeing an explosive growth in cases, hospitalizations and deaths, widespread vaccination is likely still months away, and experts are urging Americans to continue following best practices of wearing a face mask, washing their hands and maintaining social distance. But the possibility of at least one vaccine being ready in December offers hope of a reachable goal at the end of a devastating year.

Here’s a look at what we know so far about who will be able to get inoculated and how soon.

Many companies are working on vaccines. What are the differences?

Dozens of vaccines are under development worldwide, and at least 10 have reached the third phase of clinical trials, including in India and China, according to data from the Regulatory Affairs Professional Society.

We don’t know which ones will work safely to stop the coronavirus, so developing several candidates at once increases the chances that researchers will find effective vaccines. When combatting other infectious diseases, the World Health Organization says about one out of five vaccines that make it to clinical trials are successful. And even those that work for some people may not work for everyone. Older people’s immune systems may respond better or worse to one vaccine than younger people’s immune systems.

Two American drug companies — Pfizer and Moderna — have tested their vaccines on tens of thousands of people, and released data suggesting both candidates are more than 90 percent effective, though their results have not yet been vetted independently.

On a Nov. 16 call announcing the Moderna vaccine’s reported results, Dr. Anthony Fauci said having a COVID-19 vaccine with 95-percent “was really aspirational.”

“Well, our aspirations have been met,” he said.

Both require two doses each, and use a technology called messenger RNA that has never before been used in a vaccine. The two medicines must be stored at very cold temperatures. And reported side effects for each have included fatigue, fever and soreness.

On Nov. 23, a third company, AstraZeneca, announced a vaccine that was 90-percent effective if a half dose was followed by a full dose, but 62 percent effective if participants received two full doses. These results raised questions about and criticism of the company’s research and if its vaccine was actually viable.

How does the U.S. approve a vaccine?

It can normally take a decade of research and testing before a vaccine is approved. But this is not the typical process.

Pfizer and Moderna completed enough rounds of clinical trials in order to request emergency use authorization from the Food and Drug Administration for their vaccine candidates. The FDA has never granted an EUA for a vaccine under these circumstances and has only ever granted such authorization to one vaccine, which is used to prevent people from getting poisoned if they inhaled anthrax.

What is an EUA? It’s a fast-track approval that allows companies to begin distributing whatever drug or vaccine the FDA has approved.

READ MORE: 2 COVID-19 vaccine candidates may protect against the virus. Now what?

On Dec. 2, the United Kingdom authorized the Pfizer vaccine for emergency use and planned to begin vaccinating people a week later. On Dec. 8, the United Kingdom became the first country to begin inoculating its residents against the virus with the Pfizer vaccine.

On Dec. 10, an advisory committee for the Food and Drug Administration voted 17-4 with one abstention to approve the Pfizer COVID-19 vaccine for use in patients age 16 or older. Some committee members argued against the vaccine’s use in 16- and 17-year-olds, saying there was not enough data that shows how safe and effective the vaccine is for that age group. On Dec. 11, the FDA said it would work quickly to finalize Pfizer’s request for an emergency use authorization. That meant people could be vaccinated in the U.S. this month.

On Dec. 18, the FDA authorized the Moderna vaccine for emergency use in people age 18 or older, offering the U.S. its second vaccine to fight COVID-19. Aside from having a sore arm when injected with the vaccine, reported side effects included “tiredness, headache, muscle pain, chills, joint pain, swollen lymph nodes in the same arm as the injection, nausea and vomiting, and fever,” especially after the vaccine’s second dose. With the FDA’s decision, states began receiving millions of shipments of Moderna vaccines. It is yet to be seen if the Moderna vaccines will suffer the same distribution setbacks reported in getting the Pfizer vaccine to different states. In recent days, some states reported bottlenecks in shipments and were left waiting for the Pfizer vaccine to arrive. U.S. General Gus Perna, who oversees distribution logistics for COVID-19 vaccines under Operation Warp Speed, apologized for the delivery setbacks.

Who gets it first?

The U.S. began inoculating Americans against COVID-19 on Dec. 14 after the FDA and CDC authorized the Pfizer vaccine for emergency use — the first in the country. Shipments of doses were distributed nationwide, with priority for health care workers and nursing home residents. In New York, ICU nurse Sandra Lindsay was the first person statewide to get the shot.

READ MORE: Trump says he’s nixing plan for early COVID-19 vaccine at White House

Canada has contractually secured nearly nine doses per capita of pre-ordered vaccines, according to a Nov. 30 article in the journal Nature, leading the world. The U.S. is not far behind with seven doses per person, but the specifics about how those doses are divvied up — among states, or specific groups — are still a matter of debate.

On Dec. 1, the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices shared its recommendations for the initial rollout.

Health care workers and long-term care residents, essential workers, such as teachers, firefighters and police, corrections staff and transportation and agricultural workers could be the next offered the vaccine. Next up would be adults with high-risk medical conditions and those age 65 or older.

Like many aspects of the U.S. response to the COVID-19 pandemic, states have been saddled with the responsibility of developing their own plans to get people vaccinated for the virus. And when you’re talking about distributing millions of doses of vaccines that require cold storage and sensitive conditions to densely populated urban centers as well remote reaches of the country, there is plenty of room for error or disparity.

When can I get the vaccine?

Public health experts, including Fauci, have said that a vaccine could be available for use in the second half of December.

But that doesn’t mean it will be immediately available to any person in the U.S. who wants it. First, high-priority groups would get vaccinated. In a Nov. 23 interview with PBS NewsHour’s Judy Woodruff, Fauci said he expects that round of inoculations would last until the end of March. Then, in April and May, the vaccine would be more widely available to the general population, Fauci anticipated.

Fauci told Woodruff that we should use the vaccines on the horizon “as an incentive to not give up” given that it will take months to get a substantial number of people vaccinated.

“If we could just hang in there and adhere to these public health measures as we get more and more relief from the vaccines,” he said. But if the public tosses aside caution now, a lot of people could be leveled by this virus before enough get vaccinated to make a difference.

Editor’s note: This is a developing story.