Who Will Get the Coronavirus Vaccine First?

After months of deliberation and debate, a panel of independent experts advising the Centers for Disease Control and Prevention is set to decide on Tuesday which Americans it will recommend to get the coronavirus vaccine first, while supply is still short.

The panel, the Advisory Committee on Immunization Practices, will vote in a public meeting on Tuesday afternoon, and it is expected to advise that health care workers be first in line, along with residents of nursing homes and other long-term care facilities. If the C.D.C. director, Dr. Robert R. Redfield, approves the recommendations, they will be shared with states, which are preparing to receive their first vaccine shipments as soon as mid-December, if the Food and Drug Administration approves an application for emergency use of a vaccine developed by Pfizer.

States don’t have to follow the C.D.C.’s recommendations, but most probably will, said Dr. Marcus Plescia, the chief medical officer for the Association of State and Territorial Health Officials, which represents state health agencies. The committee will meet again soon to vote on which groups should be next to receive priority.

Here are answers to some common questions about the vaccine and its distribution.

Who will get the vaccine first?

Based on its recent discussions, the C.D.C. committee will almost certainly recommend that the nation’s 21 million health care workers be eligible before anyone else, along with three million mostly elderly people living in nursing homes and other long-term care facilities.

A staggering 39 percent of deaths from the coronavirus have occurred in long-term care facilities, according to the committee. But there won’t be enough doses at first to vaccinate everyone in these groups; Pfizer and Moderna, the two companies closest to gaining approval for their vaccines, have estimated that they will have enough to vaccinate no more than 22.5 million Americans by January. So each state will have to decide which health care workers go first.

They may choose to prioritize critical care doctors and nurses, respiratory therapists and other hospital employees, including cleaning staff, who are most likely to be exposed to the coronavirus. Or they may offer the vaccine to older health care workers first, or those working in nursing homes, who are at higher risk of contracting the virus. Gov. Andy Beshear of Kentucky said on Monday that most of his state’s initial allocation would go to residents and employees of long-term care facilities, with a smaller amount going to hospital workers.

It’s important to remember that everyone who gets a vaccine made by Pfizer or Moderna will need a second shot — three weeks later for Pfizer’s, four weeks for Moderna’s.

Who gets it next?

The C.D.C. committee hinted last week that it would recommend essential workers be next in line. About 87 million Americans work in food and agriculture, manufacturing, law enforcement, education, transportation, corrections, emergency response and other sectors. They are at increased risk of exposure to the virus because their jobs preclude them from working from home. And these workers are disproportionately Black and Hispanic, populations that have been hit especially hard by the virus.

Individual states may decide to include in this group employees of industries that have been particularly affected by the virus. Arkansas, for example, has proposed including workers in its large poultry industry, while Colorado wants to include ski industry workers who live in congregate housing.

After essential workers, the priority groups likely to be recommended by the C.D.C. committee are adults with medical conditions that put them at high risk of coronavirus infection, and people over 65. But again, some states might diverge to an extent, choosing, for example, to vaccinate residents over 75 before some types of essential workers. All other adults would follow. The vaccine has not yet been thoroughly studied in children, so they would not be eligible yet.

Who will make state-level decisions about priority groups?

Each state has a working group, composed largely of public health officials, that has been planning for months and making decisions about vaccination campaigns. Each state’s top health official and governor will probably sign off on final plans.

How long will states focus on one priority group before moving to the next in line?

States don’t need to reach everyone in one priority group before moving on to the next, according to the C.D.C. advisory committee. But more federal guidance is expected on the subject.

When will the first doses of a vaccine be shipped, and where will they go?

Federal officials have said they plan to ship the first 6.4 million doses within 24 hours after the F.D.A. authorizes a vaccine, and the number each state receives will be based on a formula that considers its adult population. Pfizer will ship special coolers, each containing at least 1,000 doses, directly to locations determined by each state’s governor. At first, almost all of those sites will probably be hospitals that have confirmed they can store shipments at minus 94 degrees Fahrenheit, as the Pfizer vaccine requires, or use them quickly.

When will a vaccine be available to the general public, and where will people receive it?

Federal officials have repeatedly suggested that people who are not in the priority groups — healthy adults under 65 who don’t work in health care or otherwise qualify as essential workers — should have access to the vaccine by May or June, because there will be enough supply by then. But a lot will have to go right for that to happen. One factor is whether, or when, other vaccines besides Pfizer’s and Moderna’s are approved.

Can employers like hospitals or grocery stores require their employees to be vaccinated?

Employers do have the right to compel their workers to be vaccinated. Many hospital systems, for example, require annual flu shots. But employees can seek exemptions based on medical reasons or religious beliefs. In such cases, employers are supposed to provide a “reasonable accommodation”; with a coronavirus vaccine, a worker might be allowed to wear a mask in the office instead, or to work from home.

Three companies have announced preliminary data indicating their vaccines are effective, and there are dozens of additional candidates in clinical trials. Can I choose which vaccine I get?

This depends on a number of factors, including the supply in your area at the time you’re vaccinated and whether certain vaccines are found to be more effective in certain populations, such as older adults. At first, the only choice is likely to be Pfizer’s vaccine, assuming it is approved. Moderna asked the F.D.A. for emergency authorization on Monday; if approved, it would most likely become available within weeks after Pfizer’s.

Are there any side effects from the shot?

Some participants in both Pfizer’s and Moderna’s trials have said they experienced symptoms including fever, muscle aches, bad headaches and fatigue after receiving the shots, but the side effects generally did not last more than a day. Still, preliminary data suggests that, compared with most flu vaccines, the coronavirus shots have a somewhat higher rate of such reactions, which are almost always normal signs that the body’s immune response is kicking in. At the meeting of the C.D.C. advisory committee last week, some members said it would be important for doctors to warn their patients about possible side effects and assure them of the vaccines’ safety.

How do I know it’s safe?

Each company’s application to the F.D.A. includes two months of follow-up safety data from Phase 3 of clinical trials conducted by universities and other independent bodies. In that phase, tens of thousands of volunteers get a vaccine and wait to see if they become infected, compared with others who receive a placebo. By September, Pfizer’s trial had 44,000 participants; no serious safety concerns have been reported.

The F.D.A. will also review the data for each vaccine seeking authorization and share it with its advisory committee, which will meet publicly — in the case of the Pfizer vaccine, on Dec. 10 — to ask questions and make a recommendation to the agency. The F.D.A. will then decide whether to approve the vaccine for emergency use.

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