A report released today by the Kaiser Family Foundation shows how Americans still fall largely along partisan lines when it comes to opinions about the COVID-19 booster vaccine. 

At least 82% of Democrats surveyed said the COVID booster vaccine shows that scientists are continuing to find ways to make the vaccine more effective, while 52% of Republicans say it shows that the vaccines didn’t work as well as promised. When it came to breakthrough cases—or the positive cases among the vaccinated—the majority of both Democrats and Republicans agreed that vaccines work, because vaccinated people don’t get as sick or don’t typically require hospitalization, but more than 39% of Republicans said breakthrough infections were evidence that existing vaccines aren’t working, compared to just 10% of Democrats. 

The partisanship isn’t surprising, considering how politicized the pandemic has been in the U.S. New data by the New York Times shows how vaccination rates—and COVID deaths—correspond with how people voted in the 2020 U.S. election.

The vaccines were developed quickly, and information has changed as the science has evolved, said Liz Hamel, the Kaiser foundation’s vice president who oversees public opinion research. Many people get their information from partisan sources and hear messages from partisan leaders, which has created confusion, especially among the unvaccinated, she said. “People are overwhelmed with information and trying to discern the misinformation,” said Hamel.

According to the survey, as many as 90% of Democrats say they’re vaccinated, and they’re likely to attribute the rise in Delta variant cases to people who refuse the vaccine or fail to take proper precautions. That compares to 58% of Republicans who are vaccinated and are more likely to attribute caseloads to immigrants and tourists. While vaccinated adults chalk up the surge in cases to people who won’t vaccinate, the unvaccinated argue the rise means vaccines aren’t working as well as promised.

The disparate views are driving big emotions. Two-thirds of Democrats and half of vaccinated adults say they’re angry at the unvaccinated, while 59% of Republicans and 56% of unvaccinated adults say they’re angry with the federal government. 

Vaccination rates climbed this summer—as of September, 72% of U.S. adults have received at least one dose of the vaccine, up from 67% in July. The big reasons for finally getting those shots? According to the report, more than a third of those who were recently vaccinated said they either knew someone who got sick or died from COVID, their local hospitals were filling up, or they simply observed the surge of Delta variant cases. 

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