Originally Published: 27 JUL 22 10:13 ET

Updated: 27 JUL 22 12:37 ET

By Kevin Liptak, Betsy Klein and Kate Sullivan, CNN

(CNN) -- President Joe Biden said Wednesday he's "feeling great" and is back to working in person after isolating in the White House and recovering from what has been described as a mild case of Covid-19.

The President, addressing the nation from the Rose Garden, credited the vaccines, booster shots and the Paxlovid antiviral treatment he was prescribed for averting a severe case of the virus. Biden, 79, is at high risk for a severe case of Covid-19 due to his age.

"I got through it with no fear," Biden said. "A very mild discomfort because of these essentials, lifesaving tools. And guess what, I want to remind everybody: They are free. They are convenient, and they are safe, and they work."

Biden used the moment to tout his administration's response to the pandemic and emphasized that all the tools available to him to fight off the virus are also available to every American. He drew a direct contrast with his predecessor, Donald Trump, who tested positive for Covid-19 in October 2020 before vaccines were authorized and received an experimental treatment not available to the wider public.

"When my predecessor got Covid, he had to get helicoptered to Walter Reed Medical Center. He was severely ill; thankfully, he recovered. When I got Covid, I worked from upstairs of the White House and the offices upstairs ... for a five-day period," Biden said.

He continued, "The difference is vaccinations, of course. But also new three new tools free to all and widely available. You don't need to be President to get these tools to use for your defense. In fact, the same booster shots, the same at-home test, the same treatment that I got, is available to you. My administration made sure that all Americans across the country, from all walks of life, have free access to those tools."

Biden took two antigen tests, one on Tuesday evening and one on Wednesday morning, that were both negative, his physician, Dr. Kevin O'Connor, wrote in a memo to White House press secretary Karine Jean-Pierre.

The President will wear a well-fitting mask for 10 days to prevent the spread of the virus, and he will increase the frequency with which he is tested to detect for any possible resurgence of the virus.

O'Connor cited the potential for the President to experience a "rebound" of his Covid-19 infection after Biden received the antiviral Paxlovid in explaining the more frequent testing. O'Connor noted there have been a small percentage of patients who have been treated with Paxlovid who experienced a rebound in their infection.

Biden on Wednesday continued to urge Americans to receive their vaccinations and booster shots and to "take advantage of these lifesaving tools," as the BA.5 subvariant, another offshoot of the Omicron variant, spreads within the United States. He called on Congress to continue allocating funding to make the tools widely available.

"The reality is that BA.5 means many of us are still going to get Covid even if we take the precautions," Biden said. "That doesn't mean we're doing anything wrong. Unfortunately, this Covid is still with us as it has been for two-and-a-half years. But our fight against Covid is making a huge difference. What's different now is our ability to protect ourselves from serious illness due to Covid."

Biden tweeted a photo of his negative Covid-19 test on Wednesday morning and wrote, "Back to the Oval. Thanks to Doc for the good care, and to all of you for your support."

The President tested positive on Thursday and experienced mild symptoms, including runny nose, fatigue, high temperature and a cough, according to his doctor. He continued to recover and work in isolation within the residence of the White House, and by Tuesday was feeling well enough to resume working out in the executive mansion's gym.

Biden is fully vaccinated and received two booster shots. He received his first two doses of the Pfizer/BioNTech Covid-19 vaccine ahead of his inauguration in January 2021, his first booster shot in September and his second booster vaccination in March.

The President completed a five-day course of Paxlovid, which requires a doctor's prescription and is available via emergency use authorization from the US Food and Drug Administration for treatment of mild to moderate Covid-19 in people 12 and older who are at high risk of severe illness.

First lady Jill Biden was deemed a close contact of the President but her office says she continues to test negative. Jill Biden is in Wilmington, Delaware. Vice President Kamala Harris was also deemed a close contact but continues to test negative. Harris tested positive for Covid-19 in April and her office says she did not experience symptoms.

This story has been updated with additional information.