Daily national surveys by Carnegie Mellon University show that while COVID-19 vaccine uptake has increased, the proportion of vaccine-hesitant adults remains unchanged. The concerns about a side effect remain high, especially among females, Black adults and those with an eligible health condition.

The Delphi Research Group at CMU in partnership with Facebook released its latest survey findings. The analyses show that vaccine hesitancy persists and point to potential tactics to combat it.

"Prior research by the CDC has found that Black and Hispanic adults are the least likely to receive the annual flu vaccine each year," said Alex Reinhart, assistant teaching professor in CMU's Department of Statistics & Data Science and a member of the Delphi Research Group. "Our survey suggests that COVID vaccine hesitancy follows a similar trend."

Reinhart was joined on this report by Facebook research scientists Esther Kim, Andy Garcia, Sarah LaRocca and Katherine Morris. Delphi staff, including statistical developer Nat DeFries and survey coordinator Wichada La Motte-Kerr, contributed to the development and analysis of the survey.

The survey tracks daily trends in behaviors and attitudes on issues related to COVID-19 at the state and county level. The surveys of Facebook users are conducted by members of the Delphi Research Group in partnership with Facebook's Data for Good program. The new report consists of responses obtained from more than 1.9 million Americans between Jan. 10 and Feb. 27, 2021.

According to the latest survey results, the proportion of adults who are either vaccinated or willing to be vaccinated increased from 72% to 77%, which is largely attributable to a decrease in non-responses on the survey question. Vaccine hesitancy remained relatively steady at 23%

The researchers note that vaccine hesitancy might be improved by addressing concerns about potential or perceived side effects. Seven out of 10 vaccine-hesitant adults stated they were concerned about side effects.

"When it comes to increasing vaccine acceptance, our global health partners have emphasized that there is not a one-size-fits-all approach," said Kang-Xing (KX) Jin, Facebook's Head of Health. “By understanding geographic and demographic trends in vaccine hesitancy with the help of COVID-19 Symptom Survey, paired with public insights from Facebook about how people are talking about vaccines, public health officials can design and deliver tailored messaging campaigns that resonate with specific audiences within states, counties and communities.”

The research team suggests turning to trusted local healthcare professionals to spread the word of vaccine safety and importance. Trust in local healthcare workers among vaccine-hesitant adults has increased significantly in January and February even though trust in other information outlets has decreased or remained unchanged.

“Hesitancy can reflect existing mistrust of medicine, but uptake of the COVID vaccine, just like uptake of the flu vaccine, can also reflect unequal access to healthcare or unequal availability of convenient places to get vaccinated,” said Reinhart. “We're looking into this in more detail in newer versions of the survey, which ask specifically about access to the vaccine and specific reasons for not wanting to receive it.”

Delphi researchers use the data to perform forecasts of COVID-19 activity at state and county levels, which are reported to the U.S. Centers for Disease Control and Prevention. The COVID-19 Symptom Survey is the largest ongoing COVID-19 data-collecting effort in the country, gathering more than 50,000 responses daily and more than 18 million responses total since its launch in April 2020.

Facebook distributes the surveys to a portion of its users each day as part of its Data for Good program. Facebook does not receive any individual survey information from users; CMU conducts the surveys off Facebook and manages all the findings. The University of Maryland likewise works with Facebook to gather international data on the pandemic, which can also be visualized through the Data for Good map and dashboard.