As the federal government, public health experts and scientists push toward a coronavirus vaccine, a new survey suggests only about half of Americans say they will get one when it becomes available.

The poll by The Associated Press-NORC Center for Public Affairs Research finds 49% of Americans overall say they plan to get a vaccination, while 31% of respondents say they are unsure if they will get vaccinated. The survey found 20% of respondents flat out said they will not.

When broken down by age and race, other disparities begin to emerge.

"Older Americans, and those who worry that they or someone in their household could be infected with the virus are more inclined to say they will get a coronavirus vaccine once it becomes available," researchers said.

"Black Americans are more likely than other racial and ethnic groups to say they do not plan to get the vaccine if it becomes available."

Sixty-seven percent of Americans age 60 and older say they will get vaccinated, compared 40% among those 59 years old or under.

The survey also found white Americans lead the way as far as willingness to get the vaccine, outpacing black Americans, 56% to 25%. The study found 37% of Hispanics say they will get a vaccine if it is available.

As NPR and other outlets have reported, the coronavirus has disproportionately ravaged black and Latino communities. The early hypothesis as to why that is points to long-standing health challenges, particularly among African Americans.

"Health disparities have always existed for the African-American community," Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said in an interview with NPR last month.

He added that the crisis is "shining a bright light on how unacceptable that is."

There also is a history of mistrust between black Americans and public health, perhaps most notably after the Tuskegee experiment of the 1930s.

That's where researchers and the federal government duped hundreds of black men into thinking they were receiving medical treatments for "bad blood" when in reality the scientists were allowing them to die of untreated syphilis.

The Centers for Disease Control and Prevention points out the experiment was slated to last for six months but it went on for 40 years.

Of the overall respondents that say they will not get the vaccine, 70% raise concerns about the side effects and 42% say they are fearful of contracting the virus from the vaccine.

It is important to note that the best estimates for any COVID-19 vaccine becoming available is still months away, so the 1,056 adults surveyed are responding to what is still a hypothetical scenario.

Some experts suggest aiming for hundreds of millions of doses of the eventual vaccine to be ready for distribution in the United States by January 2021.

The survey was conducted May 14-18 and has a margin of sample error of 4.2 percentage points.

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