What to know about President Joe Biden's case of COVID-19

President Joe Biden tested positive for COVID-19 on Wednesday, but will continue to work, the White House said − a development that comes as Biden is facing increasing pressure to drop his reelection effort.

"He is vaccinated and boosted, and he is experiencing mild symptoms," according to a statement from Press Secretary Karine Jean-Pierre.

Biden, who is 81, took to X to confirm the news, writing that he is "feeling good" and wanted to "thank everyone for the well wishes."

 "I will be isolating as I recover, and during this time I will continue to work to get the job done for the American people," the post says.

He was returning to Delaware, where he will self-isolate and continue to carry out all of his duties fully. The White House said they will continue to provide updates on Biden's status.

Here's what to know.

President Joe Biden was in Las Vegas shortly before testing positive

Biden traveled to Las Vegas on Tuesday, where he spoke at the NAACP's national convention, giving an "impassioned speech" in an effort to secure votes, USA TODAY reported.

The White House said it learned of Biden's illness on Wednesday, a day after he hit the stage for his first event in Las Vegas. Biden’s doctor, Kevin O’Connor, said the president was dealing with "upper respiratory symptoms," including a running nose, cough and fatigue.

"He felt okay for his first event of the day, but given that he was not feeling better, point of care testing for COVID-19 was conducted, and the results were positive for the COVID-19 virus," according to a statement from O'Connor.

Though Biden's symptoms are mild, his respiratory rate, temperature, and pulse oximetry are all within the normal level, O'Connor said.

"The President has received his first dose of Paxlovid. He will be self-isolating at his home in Rehoboth," O'Connor added.

How many times has Biden had COVID?

Biden has tested positive for COVID-19 three times in the last couple of years, reporting "mild symptoms" each time, USA TODAY reported.

Below are the dates Biden has reported testing positive for COVID-19:

• July 17, 2024
• July 30, 2022
• July 21, 2022

Biden tested positive twice within the span of nine days in July 2022, with O'Connor attributing the cause of the second positive result as a "virus rebound," which sometimes occurs in patients treated with antiviral medication Paxlovid.

Older adults at risk for 'getting very sick' from COVID-19

Older adults face the "highest risk" for getting very sick from COVID-19. Over 81% of deaths occur in people over the age of 65, according to the Centers for Disease Control and Prevention.

The number of deaths in adults over the age of 65 is 97 times higher than among people ages 18-29 years, according to the CDC.

Country sees surge in COVID cases, CDC says

The CDC reported recently that "COVID-19 levels have increased in most states" based on wastewater sample data, USA TODAY reported.

Wastewater viral activity level for COVID-19 is "high" and "very high" in 26 states across the country, with the West and South having shown the largest increase of COVID-19 levels.

"More than 70% of the illnesses stem from the highly contagious JN.1 strain, which grew more prevalent over the winter. These COVID-19 variants are known as FLiRT variants," according to USA TODAY reporting.

The prevalence of JN.1 has steadily declined since May, while cases of other variants, including KP.3 and KP.2 have increased. For the two weeks from June 22 to July 6, the leading variant in the country was KP.3, accounting for 31.3% of infections, USA TODAY reported.