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The essential COVID-19 vaccine FAQ

The COVID-19 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.

With widespread vaccination 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.

Here’s a look at what we know so far.

Many companies are working on vaccines. Why?

Developing several vaccine 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.

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.

Before the coronavirus pandemic, the FDA had never granted an EUA for a vaccine under these circumstances and had 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.

Both vaccines from Pfizer and Moderna have been shown to be more than 90-percent effective, 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 Feb. 26, the FDA advisory committee unanimously voted to support the authorization of a third vaccine for emergency use, and the agency did so the next day. This latest addition to the U.S. vaccine supply is a single-dose vaccine from Johnson & Johnson that requires normal refrigeration and has been shown as 72-percent effective in preventing coronavirus infections in the U.S. That data emerged after researchers conducted clinical trials with about 40,000 volunteers between ages 18 and 100. Advocates have said the one dose and easier storage could make this vaccine a more accessible option, even though this vaccine appears to be somewhat less effective than those that were authorized earlier.

In April, after 6.8 million people had gotten the Johnson & Johnson vaccine, reports emerged that six people had developed rare but severe blood clots after receiving the single-dose shots. Federal regulators recommended a pause on the vaccine—which accounted for less than 5 percent of the nation’s total vaccine rollout, according to the White House COVID-19 Task Force—out of an “abundance of caution” and to investigate the findings. The pause lasted 10 days and on April 23, the CDC’s advisory committee voted to resume use of the Johnson & Johnson vaccine.

On March 22, pharmaceutical company AstraZeneca announced its COVID-19 vaccine candidate was 79-percent efficacious in preventing virus symptoms and 100 -percent efficacious against development of severe illness and hospitalization. The data came after the on completion of phase III clinical trials with more than 32,000 participants. Among study participants 65 or older, vaccine efficacy was 80 -percent. The vaccine’s two doses are administered four weeks apart and can be stored using normal refrigeration. Questions have arisen in recent months about this particular vaccine and whether it may cause blood clots. Several countries in Europe suspended use of the vaccine, but on March 18, the European Medicines Agency said the vaccine was “not associated with clots” and that its benefits in gaining control over the pandemic far outweigh risks.

Controversy continued to grow around AstraZeneca’s vaccine announcement after an independent review body said the pharmaceutical company misrepresented their results. The independent groups said data suggested the vaccine was less effective than the company had initially suggested. On March 24, AstraZeneca said its vaccine candidate was 76 percent effective in preventing severe symptoms, a lower rate than the 79 percent the company announced earlier in the week.

Who got it first and why?

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 my kids get vaccinated?

So far, the U.S. has not authorized any COVID-19 vaccine for emergency use for people younger than age 16. Only one vaccine — Pfizer’s — can be administered for those age 16 or older.

Researchers say there is not yet enough data to know if vaccines are safe and effective for children. For months, the American Academy of Pediatrics has urged the research community to pursue clinical trials, which currently include children as young as age 12, to understand how effective the vaccines are in protecting younger populations. At the same time, the organization has encouraged pediatricians to vaccinate older caregivers so they face a reduced risk of getting infected, seriously sick or worse.

On Feb. 28, Dr. Anthony Fauci, the nation’s leading infectious disease expert, said during an interview on NBC News’ “Meet the Press” that he expected to see vaccines available for elementary school children by the end of 2021 or early 2022.

How can I find a vaccine?

As more communities open up access to vaccines beyond older adults and health care workers, people may have questions about or difficulties securing an appointment for themselves and loved ones. In some places, demand has crashed sign-up websites, and the process can feel frustrating or opaque.

READ MORE: 8 tips for finding a COVID-19 vaccine

If you need tips for finding a vaccine, check with your primary care doctor, local pharmacies and your local or state health department.

Then, read all online documentation, sign up wherever you qualify and be flexible in your availability. It is important to be patient, but especially to not put your health at risk while waiting in lines and hunting down a vaccine.

Editor’s note: Johnson & Johnson is a funder of the PBS NewsHour.