The development of a coronavirus vaccine is fast becoming an issue in the presidential race as Democratic nominee Joe Biden questions whether the public can trust the Trump administration to safely develop and distribute a vaccine.

The Trump campaign is accusing the former vice president and his running mate, Sen. Kamala Harris (D-Calif.), of “spreading anti-vaccine conspiracy theories” it says will keep people from getting vaccinated.

Biden says it is President Trump who is politicizing the development of a vaccine by rushing the government to produce one without proper protections for health.

“We can’t allow politics to interfere in the vaccine in any way,” Biden said Wednesday following a private meeting with a team of seven science advisers, many of whom had ties to the Obama administration.

“Americans have had to endure President Trump’s incompetence and dishonesty when it comes to testing and protective equipment … so let me be clear — I trust vaccines. I trust scientists. But I don’t trust Donald Trump. At this moment, the American people can’t either,” Biden said.

The Trump campaign and its allies are reacting with fury to Biden’s actions, arguing he is fearmongering.

“It’s very, very disappointing to hear presidential candidate Joe Biden and his vice presidential running mate Kamala Harris downplaying this and saying they wouldn’t take it,” said Rep. Brad Wenstrup (R-Ohio), a former podiatrist and a member of the Congressional Doctors Caucus. “That’s very dangerous for the health of America.”

Trump and the White House have also taken a series of steps to indicate they are moving as quickly as possible to get a vaccine available. On Wednesday, the administration outlined a strategy to deliver free COVID-19 vaccine doses to the public.

The context for the battle is a tight presidential race likely to come down to a handful of swing states. Biden is leading in polls in most of these states, and the polls also show Trump has been hurt by negative voter attitudes toward his handling of the pandemic.

The discovery of a vaccine would dramatically alter the presidential race, giving hope to people that there is light at the end of the tunnel.

Public health experts have expressed worries that the politicization of the coronavirus and the search for a vaccine could make people less likely to take it.

A recent Morning Consult poll found that 51 percent of the public says they’d be willing to take the COVID-19 vaccine if one became available, down 21 points from April. The drop is equal among Republicans and Democrats.

Neither Biden nor Harris has committed to taking a Food and Drug Administration-approved vaccine while Trump is in office, but Anthony Fauci, the government’s top infectious disease expert and a figure trusted by most Democratic politicians, has said the process around the vaccine has been free from political interference and that he would not hesitate to take an FDA-approved vaccine.

New data from the Harvard CAPS-Harris Poll finds that about two-thirds of voters don’t expect a vaccine to be available until next year. Sixty-four percent say they’re likely to take the vaccine as soon as it is available, with 56 percent saying they trust the FDA will only clear an emergency vaccine once it is ready for consumption.

Still, 80 percent are concerned about political pressure on the FDA.

“The polling shows that voters would regard an announcement of a vaccine before the election as a surprise, surpassing expectations of no vaccine until next year,” said Mark Penn, co-director of the Harvard CAPS-Harris Poll. “They will be skeptical over whether the FDA was pressured into an early announcement but ultimately trust the agency’s decision. A vaccine could well be this year’s October surprise.”

A vaccine is far from certain this year.

Centers for Disease Control and Prevention (CDC) Director Robert Redfield told Congress on Wednesday that a vaccine will not likely be available to the general public until the “second or third quarter” of next year, although he said it’s possible one will be available for first responders as early as November.

Trump disputed that characterization in an evening press conference, calling it “incorrect information.”

“I think he just made a mistake,” Trump said of Redfield. “He misunderstood the question.”

The president has said that a vaccine could be ready within four to eight weeks and that he'd spoken reguarly to both Redfield and Stephen Hahn, the head of the Food and Drug Administration. 

The president has also accused government officials of slow-walking the vaccine in an effort to harm his reelections chances.

Democrats, meanwhile, are raising concerns about corruption and mismanagement at the Department of Health and Human Services (HHS).

HHS announced Wednesday that Michael Caputo, the top communications official at the agency, would take a medical “leave of absence” after he accused government scientists of plotting against Trump and encouraged the president’s supporters to buy ammunition.

There are media reports that Caputo’s team sought to interfere with scientific research from the CDC. Senate Minority Leader Charles Schumer (D-N.Y.) has called on HHS Secretary Alex Azar to resign.

Polls show trust in scientific and political institutions has eroded significantly amid the political battles over a coronavirus relief package, the economic shutdown and speculation about a vaccine.

A poll conducted by the Kaiser Family Foundation found 67 percent of Americans have a great deal or a fair amount of trust in the CDC to provide reliable information about the coronavirus, down 16 points from April.

Biden on Wednesday said the Trump administration must outline the criteria used to determine the safety and effectiveness of a potential vaccine, and produce scientific witnesses to testify that politics were not a consideration, before the public buys in.

“Scientific breakthroughs don’t care about calendars any more than the virus does,” Biden said. “They certainly don’t adhere to election cycles. And their timing, approval and distribution should never ever be distorted by political considerations. They should be determined by science and safety alone.”