Dr. Anthony Fauci, the government's top infectious diseases expert, emphasized the dangers of COVID-19 on Tuesday, contradicting President Donald Trump's false claim that the coronavirus was only as deadly as the flu.
People infected with COVID-19 do display "flu-like" symptoms, Fauci said Tuesday in an interview with NBC News' Kate Snow. But the damage the coronavirus can do "is very much different from influenza."
"You don't get a pandemic that kills a million people and it isn't even over yet within influenza," said Fauci, director of the National Institute of Allergy and Infectious Diseases. "So it is not correct to say it's the same as flu. It has some overlapping symptomatology early on. But flu doesn't do the things to you that COVID-19 can."
Trump, still infected, was released Monday from Walter Reed National Military Medical Center after three days of treatment. He returned to the White House, where he resumed downplaying the dangers of the virus, which has already killed more than 210,000 people in the United States, according to the latest NBC News figures.
"Flu season is coming up! Many people every year, sometimes over 100,000, and despite the Vaccine, die from the Flu," Trump tweeted. "Are we going to close down our Country? No, we have learned to live with it, just like we are learning to live with Covid, in most populations far less lethal!!!"
Trump's cavalier attitude toward COVID-19 and his boastful tweets about his apparent recovery, coupled with his insistence on taking off his mask for a photo opportunity upon returning, angered coronavirus survivors and those who have lost loved ones.
Asked about Trump's messaging, Fauci opted not to antagonize the president.
"I have a job to do, and my personally contradicting the president of the United States publicly is not a good thing if I want to get my job done," Fauci said.
Instead, he reiterated the message he has been repeating for months as the country has been logging 40,000 new COVID-19 cases a day and continues to lead the world with more than 7.5 million confirmed cases.
"There are some things that should be universally practiced, and that is the universal wearing of masks, avoiding crowds, keeping a distance, doing things outdoors more than indoors and washing our hands frequently," Fauci said. "That doesn't matter who you are. That's what you should be doing."
Pressed by Snow about the "mixed messaging" coming out of the White House, Fauci said: "This is not a trivial disease. People in the United States should realize that it is not a trivial disease."
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While the White House has been pushing for rapid approval of a COVID-19 vaccine, Fauci said he is on the side of the Food and Drug Administration, which released new stricter guidelines.
That having been said, Fauci said that at the moment there are "five candidates" in the third phase of advanced trials involving thousands of people. "It is very likely that we will know by November or December of 2020 that we have a safe and effective vaccine," he said.
Trump has suggested several times, without providing evidence, that a vaccine could be ready by Election Day.
That is highly unlikely, Fauci countered, yet again.
"It is conceivable that we will know earlier, like in October. I think that is unlikely but not impossible," Fauci said. "I feel cautiously optimistic, Kate, that we will have a safe and effective vaccine that will be able to be distributed by the end of this year or by the beginning of next year."
Fauci has previously disagreed with Trump and survived a White House attempt to discredit him after he contradicted the president's more optimistic assessment of the progress of the pandemic.
This story originally appeared on NBCNews.com.