People sit in an observation area after receiving the Moderna coronavirus vaccine at an immunization event organized by the Association of Latino Professionals for America held at the Leon de Juda evangelical church in Boston on March 18, 2021. (Adam Glanzman/For The Washington Post)

Nearly half of adults in the United States who have not received a coronavirus vaccine are concerned about missing work as a result of side effects from the shot, according to a Kaiser Family Foundation poll released this month. The findings highlight a key obstacle to vaccination, particularly for the 25% of American workers who do not have any paid sick leave.

Economic stimulus legislation created tax credits that reimburse some employers for granting time off to get vaccinated or recover from side effects. But employers are not required to provide this leave. Although many employers are offering time off for employees to receive a vaccine, it's the recovery that has workers more worried.

Concerns about missing work were particularly acute among Black and Hispanic workers. According to Kaiser Family Foundation polling, Black and Hispanic adults are less likely to have received a coronavirus vaccine than White adults.

About a quarter of Americans in private industry did not have paid sick leave as of March 2020, according to the most recent data available from the Bureau of Labor Statistics. An earlier study, which broke this data down by race, ethnicity and education, found that Black and Hispanic workers, as well as workers without college degrees, were less likely to have paid leave than the country as a whole.

Those groups are also less likely to have received at least one dose of a vaccine, according to Kaiser Family Foundation polling.

Missing time is a reasonable concern. Although serious side effects from coronavirus vaccines are rare, in clinical trials, about one in six people ages 18 to 55 had a fever after their second dose of the Pfizer-BioNTech or Moderna vaccine, and about 1 in 8 had a fever after the one-dose Johnson & Johnson vaccine.

"One major barrier for people who say they want to get vaccinated as soon as possible is that they're too busy," said Liz Hamel, vice president of public opinion and survey research at the Kaiser Family Foundation. "They don't have time off. These are people who don't need convincing — they just need access."

Whether they have access is, for now, in the hands of their employers. Although the March stimulus bill created tax credits for small- and medium-sized businesses to reimburse the costs of vaccine-related time off, they aren't required to do so, and about half of American workers in the private sector are employed by businesses that are too big to qualify for the credits.

Some large businesses have chosen to give employees paid time off anyway. Boeing and Darden, for instance, provide two hours of paid leave per vaccine dose. But when it comes to side effects, employees are expected to use sick leave.

About one in five of the unvaccinated Americans in the Kaiser survey said they wanted to get the vaccine as soon as possible. But even for those who did not — the "vaccine hesitant" group — providing paid leave could make a big difference. The Kaiser Family Foundation found that more than half of vaccine-hesitant Hispanic workers would be more likely to get vaccinated if their employers provided time off to recover from side effects.

"Early on, the focus was more on how to get people appointments and have supply to keep up with demand," Hamel said. "Now, we have enough supply, so it's more about what is keeping people from getting the vaccine."