Updated July 27, 2022 at 12:29 PM ET

President Biden tested negative for COVID-19 Tuesday evening and Wednesday morning, according to a letter from his physician, and has discontinued isolating at the White House.

The president, who is fully vaccinated and twice boosted, first tested positive on July 21. He had been isolating at the White House since, appearing virtually for meetings and briefings.

In public remarks in the Rose Garden not long after the letter's release, Biden emphasized that the more transmissible BA. 5 variant will mean people will continue getting sick but that there are now more protections against severe illness. He suggested mask wearing in crowded indoor places.

"Unfortunately this COVID is still with us, but our fight against COVID is making a huge difference," he said, arguing that even if cases are up, deaths are down 90% from when he took office.

The president urged Americans to get COVID vaccines and booster shots and promoted the White House's free at-home tests as well as the use of the drug Paxlovid.

"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 in the White House," he said. "You don't need to be president to use these tools to use for your defense."

The letter says Biden's symptoms are 'almost completely resolved'

Dr. Kevin O'Connor says that Biden remains fever-free and has not used Tylenol in the last 36 hours, and as he said on Tuesday, the president's symptoms "are almost completely resolved."

O'Connor says Biden will "increase his testing cadence" due to the risk of a rebound of his COVID infection as some patients treated with Paxlovid have experienced. The president completed his five-day course of that treatment on Monday evening. The letter did not specify how frequently Biden would be tested.

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