Maine hit an important milestone last week, when more than half the population eligible for a COVID-19 vaccine had received at least one shot.

That means we may be just four to five weeks away from having a majority of the state fully vaccinated – making them highly unlikely to catch or spread the virus.

If Mainers continue to get vaccinated at this rate, we are on track for a much more normal Maine summer than many had predicted.

Just how normal will it be? People who have been fully vaccinated are starting to find out.

New cases are still at such high levels that there can be no general loosening of pandemic protocols. But common sense and reasonable risk assessment tell us that there is a distinction between what is safe for a vaccinated person and what is safe for someone who is not.

The U.S. Centers for Disease Control and Prevention has relaxed its guidance for people who are at least two weeks past their final vaccine dose.

Because new cases are still on the rise, large, indoor gatherings are not recommended, even for people who have been vaccinated. Facial coverings are still recommended while the virus is still spreading at unacceptable levels. But, according to federal public health officials, it is safe for fully vaccinated people to:

• Visit unmasked with other fully vaccinated people inside a home.

• Visit unmasked with one household of unvaccinated people who are not at risk of severe illness.

• Travel domestically or internationally, subject to local requirements for testing and quarantine.

Maine has not yet updated the guidance for fully vaccinated people, but the sooner that is done, the better. Mainers who have been following the rules for more than a year are getting tired and need some relief. And people who are trying to decide whether getting a vaccine is worth the trouble need the incentive.

It would be good if Maine’s public health officials use what we have learned about this coronavirus and how it spreads over the last year.

Last spring, a lot of attention was paid to the need to sanitize surfaces because that has been effective in slowing the spread of other viruses. But researchers have found that doorknobs, countertops and other surfaces have not been a major source of COVID infection. We are still advised to wash our hands and sanitize surfaces, but it’s not stressed as much as wearing masks and avoiding indoor gatherings.

Now, there should be more nuanced guidance based on what we have learned so far.

There is substantial evidence that COVID spreads indoors, so it’s important that people wear masks and maintain safe distances inside. But is the same true for outdoor spaces?

There have been some cases of people spreading the virus outside, but how close they are to each other and how long they are together play important roles.

Two unmasked people walking in different directions on the same sidewalk, passing each other in the open air for a second or two, would be a fairly low-risk encounter for unvaccinated people. For fully vaccinated people, it would be even lower.

Is it low enough? The public health guidance has not been clear.

Refining the rules for fully vaccinated people is different from the premature reopening that has taken place in some states. One uses the best available information to help people make choices that are safe, while the other doesn’t distinguish between what’s safe and what isn’t.

Public health officials are right to focus on vaccinating Mainers as quickly as possible. But as a substantial number of Mainers are fully vaccinated, it’s also time to discuss what comes next.