Among Americans who have recently been vaccinated against Covid-19, the key factors motivating their choice to get vaccinated are the threat of the delta variant and rising hospitalization numbers, according to a new poll from the Kaiser Family Foundation (KFF).

Why Americans are getting vaccinated

For the poll, KFF surveyed 1,519 people from Sept. 13 through Sept. 22. It defined "recently vaccinated" as those who had received their first dose after June 1. Respondents were asked why they had chosen to get vaccinated, and they were able to cite multiple reasons for their decision.

Among the recently vaccinated respondents, 39% cited rising Covid-19 cases due to the delta variant as a major reason why they got vaccinated, while 38% cited concerns about local hospitals and ICUs filling up with Covid-19 patients.

According to Drew Altman, CEO of KFF, "When a theoretical threat becomes a clear and present danger, people are more likely to act and to protect themselves and their loved ones."

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The poll also suggested that, moving forward, employer vaccine mandates could lead many currently unvaccinated individuals to consider vaccination. In particular, about one-third of unvaccinated people said they would be likely to get a shot if faced with such a mandate.

However, when asked if they would get vaccinated or take a weekly Covid-19 test, 56% of unvaccinated respondents said they'd prefer to get tested weekly, compared to 12% who said they'd get vaccinated.

How vaccinated and unvaccinated Americans feel about boosters

The poll also found a sharp split in how vaccinated and unvaccinated people perceive the potential need for Covid-19 vaccine booster shots. Overall, 78% of vaccinated respondents said the potential need for booster shots suggests scientists are finding ways to make the vaccines more effective, compared to just 22% of unvaccinated respondents.

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On the other hand, 71% of unvaccinated respondents said the need for booster shots suggests the vaccines don't work as well as promised, compared to just 19% of vaccinated respondents.

A similar split emerged when respondents were asked about the helpfulness of information they've heard about booster shots. Of those at least partially vaccinated, 54% of respondents said information about booster shots has been helpful, compared to 35% who said they found it confusing. But among the unvaccinated, 45% said they found booster shot information confusing, compared to 24% who found it helpful. (Hoffman, New York Times, 9/28; Coleman, The Hill, 9/28; Hamel et al., KFF Covid-19 Vaccine Monitor: September 2021, 9/28)