Young, healthy people will be at the back of the line for coronavirus vaccines, and they'll have to maintain their sense of urgency as they wait their turn — otherwise, vaccinations won't be as effective in bringing the pandemic to a close.

The big picture: "It’s great young people are anticipating the vaccine," said Jewel Mullen, associate dean for health equity at Dell Medical School at the University of Texas at Austin. But the prospect of that enthusiasm waning is "a cause for concern," she said.

Where it stands: Right now, young Americans are eager to get vaccinated.

• 62% of adults 18-44 years old say they would be willing to get a coronavirus vaccine, Gallup polling shows.
• 75% of students nationwide said they would probably or definitely take an FDA-approved vaccine, according to new polling from Generation Lab.

Yes, but: The most vulnerable people — frontline workers, seniors and people with underlying health problems that can cause severe coronavirus illness — will be the first priority as a limited number of vaccine doses become available.

• The lowest-risk Americans — generally, people who are young and healthy — may not get access to the vaccine until 2022, the World Health Organization's chief scientist recently predicted.
• "As more people get vaccinated, young people may think, ‘Oh, other people got it, so I don’t have to worry about it so much," Mullen said.

How it works: The WHO has estimated that roughly 60-70% of the U.S. population would need to get vaccinated in order to achieve herd immunity, the key to stopping the virus from spreading widely.

• That's only achievable if a lot of low-risk people get vaccinated.

Between the lines: The seasonal flu vaccine is important not just to protect yourself from getting the flu, but to ensure you don't then pass it to someone who's more likely to die from it, including the elderly.

• But in 2017, only about one-third of 18-49 year-olds received their flu shot.

The bottom line: The first phases of a vaccination campaign will shield the most vulnerable, hopefully causing deaths and serious illnesses to fall significantly.

• But putting the pandemic behind us will require lower-risk people to stay vigilant even after the tide begins to turn.