A line of people wait to enter the Cross Insurance Center in Bangor on Wednesday, the first day that all Mainers 16 and older were eligible to receive the COVID-19 vaccine. Credit: Linda Coan O'Kresik / BDN

Despite some good news about the coronavirus pandemic — Maine leads the nation in the percentage of adults fully vaccinated against the disease, for example — there are worrying signs that COVID will continue to sicken and kill far too many Americans. In Maine, the number of new cases remain high and hospitalizations are rising.

The United States has vaccinated the most people of any country in the world and ranks in the top 10 for the percentage of the population that has received at least one dose of a vaccine. However, a quarter of Americans say they do not plan to get vaccinated. Although the share of people who say they plan to skip the vaccine is shrinking, if a large number of Americans do not get inoculated, experts warn that herd immunity — the level of immunity needed to protect the entire population from a disease — is in jeopardy.

There is also concerning news that the number of people who have skipped a second dose of a COVID vaccine, when it is necessary, is growing.

There are three COVID-19 vaccines in use in America. Inoculations made by Pfizer and Moderna require two shots — three or four weeks apart, respectively — to be fully effective. The vaccine made by Johnson & Johnson requires only one shot.

More than 5 million people, about 8 percent of the total who got a first Pfizer or Moderna shot, have not received their second dose when it was scheduled, according to data from the U.S. Center for Disease Control and Prevention. The rate has risen as vaccine distribution has extended to the population at large.

There are many reasons that people may skip a second dose including concern about side effects, scheduling difficulties and not being in the same place where they received their first vaccine. Some pharmacies outside of Maine have not had second doses of the same vaccine available, but they have worked to reschedule or move appointments to get customers their second shot.

“I’m very worried, because you need that second dose,” Dr. Paul Offit, a professor at the University of Pennsylvania and a member of the Food and Drug Administration’s vaccine advisory panel, told The New York Times.

Missing a second dose can be problematic because it does not trigger the full immune response needed to ward off COVID’s worst consequences. One dose is also less effective against the variants of COVID that have emerged in different parts of the world. However, receiving one dose is better than none at all.

Missing second doses does not appear to be a large problem in Maine. The system that the Maine Centers for Disease Control uses to report COVID-19 vaccinations to the federal government shows that fewer than 2 percent of Maine people are overdue for a second dose.

Vaccine clinic administrators in Maine have taken steps to ensure people received a second vaccine dose. Some schedule the second shot when Mainers schedule their first vaccination using an online or telephone registration system. Others schedule the second shot at the time the first one is administered.

Some other states have initiated efforts to reach people who are overdue for a second vaccination. In Arkansas, for example, state workers have been calling those who are overdue for a second vaccination. In South Carolina, one health care system set up a program specifically for people who were overdue for a second Pfizer shot.

Many college students received a first dose of the vaccine on or near campus but will leave school before they are due for a second dose. Health officials in Pennsylvania instructed vaccine providers to give shots to college students who had received their first doses elsewhere. The University of Maine held a clinic on Wednesday, offering both the two-dose Moderna vaccine and the one-shot Johnson & Johnson vaccine in an effort to vaccine students before the end of the semester.

The message, no matter which COVID vaccine you receive, remains the same: Being vaccinated, if you are able, is a vital part of slowing the spread of the coronavirus and slowing the development of new variants, which can be more virulent and dangerous. If you receive the Pfizer or Moderna vaccine, make sure you come back for the second shot. It will protect you and your community.

The BDN Editorial Board

The Bangor Daily News editorial board members are Publisher Richard J. Warren, Editorial Page Editor Susan Young, Assistant Editorial Page Editor Matt Junker and BDN President Todd Benoit. Young has worked...