Beginning next week, Maine is expected to begin receiving a dramatic increase in the number of vaccine doses coming to the state. Combined with an ever-increasing number of vaccination sites both large and small, that puts Mainers in the best position yet to get vaccinated against COVID-19. In less than one month, every adult will be eligible to schedule a vaccination appointment.

Here are some of the latest answers to questions that have arisen about the vaccines and Maine’s pandemic restrictions:

The state launched a new registration website for vaccines this week. What does it do?

More than three months after vaccinations began, the state launched a vaccination registration website without much fanfare. The site, vaccinateme.maine.gov, is not the centralized system the state originally envisioned, but the hope is that it might fill the gaps of online systems maintained by the state’s largest health providers, MaineHealth and Northern Light Health, which have managed the majority of vaccination clinics to this point.

Anyone who is interested in getting vaccinated at a smaller or newer vaccination site might opt to use the state’s website. Although it is still being developed, users eventually will be able to schedule appointments directly through the site.

“Preregistration via this platform effectively allows folks to raise their hand and say, ‘I’m interested in being vaccinated and being informed of when there is an appointment that I can schedule into,’” Dr. Nirav Shah, director of the Maine Center for Disease Control and Prevention, said on Thursday.

For those who already are eligible, the site directs users to a list of dozens of vaccination sites that are up and running where people can inquire about an appointment.

What is the updated timeline for vaccinations?

Maine’s vaccination plan has evolved since it was created late last year, and is now a mostly age-based system built around the knowledge that older people have the greatest risk of death or serious illness if they contract COVID-19.

As of Tuesday, anyone 50 or older can schedule a vaccination appointment. Also, teachers, school staff and licensed child care workers of any age can get a vaccine. Beginning April 19, all adults in Maine will be eligible to schedule a vaccination.

As of Wednesday, 29 percent of residents had received at least one dose and 17.5 percent had been fully immunized.

Can I choose which vaccine I get?

There is no mechanism for people to choose which vaccine they will receive among the three that have been granted emergency use authorizations by the U.S. Food and Drug Administration. Shah and other health experts have encouraged people to take the vaccine that is offered to them as a way to get as many people as possible vaccinated with a goal of reaching herd immunity.

However, because Pfizer’s vaccine requires ultra-cold storage, that option is unlikely to be offered at, say, a pharmacy location. In fact, pharmacies have been receiving the bulk of Johnson & Johnson vaccine through a partnership with the federal government, so scheduling an appointment at a pharmacy may increase the chance of receiving a Johnson & Johnson vaccine.

Next week, Maine is expected to receive 23,400 doses of the Pfizer vaccine, 13,700 doses of Moderna, and 8,100 doses of Johnson & Johnson. That doesn’t include doses that will go directly to pharmacies.

What are the major differences between the three vaccines?

The Yale University School of Medicine has a good explainer on the three vaccines online at: yalemedicine.org/news/covid-19-vaccine-comparison.

The Pfizer and Moderna vaccines were developed using mRNA technology, which delivers a piece of genetic code from the coronavirus to host cells in the body. That code gives cells instructions for making copies of spike proteins, which stimulate an immune response that produces antibodies and develops memory cells to recognize and respond if the body is infected with the actual virus, according to the Yale experts.

The Johnson & Johnson version is what’s known as a carrier vaccine, a more traditional type of vaccine that involves injecting an inactive adenovirus (a common virus) as a shell to carry genetic code on the spike proteins to cells in the body. The body’s immune system is then trained to create antibodies and memory cells to protect against an actual infection.

Perhaps the biggest difference for users is that the Pfizer and Moderna options require two shots, taken either three or four weeks apart, while Johnson & Johnson requires only one dose.

What does efficacy rate mean?

All three of the vaccines now in use went through rigorous clinical trials before FDA authorization, to assess not only their safety but their efficacy.

The Pfizer vaccine was found to be 95 percent effective, the Moderna 94 percent and the Johnson & Johnson 72 percent.

But those rates are often misunderstood. For instance, if 100 people were to get the Pfizer vaccine, it does not mean five of those people would get COVID-19 if exposed to the virus. In fact, the percentage of people in clinical trials who received the vaccine and then contracted the virus was about 0.04 percent.

The efficacy rate actually means that those who received Pfizer’s vaccine had a 95 percent lower risk of getting COVID-19 than those who were not vaccinated.

Perhaps more important than the efficacy rate is this: All three vaccines were 100 percent effective at preventing severe disease. Zero vaccinated people in any of the trials were hospitalized or died of COVID-19 after the vaccines had fully taken effect.

If I’ve been vaccinated, why do I still need to wear a mask in public?

Many people who have been vaccinated likely have visions of ceremoniously ditching their face coverings, but health experts say that’s premature for public settings. Here’s why:

People who have been vaccinated are protected, but they can still be carriers of the virus, have no symptoms and spread it to others. Although vaccines are highly effective, they are not 100 percent, and there is no way to know which of the people you encounter might be vaccinated or not. The recommendations from Dr. Anthony Fauci, the country’s top infectious-disease specialist, and others are to keep wearing masks in public settings until herd immunity is achieved.

Some states – Texas and Mississippi, among them – have rescinded their statewide mask mandates despite these recommendations. Maine’s face covering policy remains in effect.

I’m a parent who’s been vaccinated. If I want to bring my children to visit another household where the adults have all been vaccinated but the children have not, what should I do?

This one is tricky. Updated U.S. CDC guidelines released this month say a vaccinated person can safety visit other vaccinated people inside without masks or distancing. The guidelines also say a vaccinated person can visit unvaccinated people who are considered low risk, including children. This is welcome news to grandparents everywhere who had been deprived of hugs with their grandchildren.

But what about gatherings of children from different homes who have not been vaccinated? The CDC still recommends that children wear masks and distance when possible. Although children are generally at low risk for COVID-19, they make up a growing percentage of new cases.

When will a vaccine be approved for children?

The Pfizer vaccine has been approved for anyone 16 and older; the Moderna and Johnson & Johnson options have been approved for those 18 or older.

Pfizer and Moderna both have completed enrollment for studies of children 12 and older, with data expected on those trials this summer. If the FDA clears the results, younger teens could start getting vaccinated once supply allows, perhaps before school starts in the fall. For children under 12, it could be 2022 before they are approved for a vaccine.

There are some changes coming Friday to Maine’s pandemic restrictions. What are they?

Beginning Friday, bars and tasting rooms in Maine will finally be allowed to open, although they will still be subject to some restrictions, including capacity limits of 50 percent of the maximum allowed. Patrons also must wear face coverings to and from their table.

Also, all indoor gatherings can increase to 50 percent of a building’s capacity and outdoor gatherings can increase to 75 percent of capacity. Mask requirements still apply.