The White House announced today that the First Lady has contracted Covid while on holiday with her family, including Mr Biden, in South Carolina.
Ms Biden is reportedly experiencing mild symptoms.
Elizabeth Alexander, the first lady’s communications director, announced the positive test.
She added that Ms Biden will remain in South Carolina until she receives two negative COVID-19 tests.
Ms Alexander said in a statement: “After testing negative for COVID-19 on Monday during her regular testing cadence, the First Lady began to develop cold-like symptoms late in the evening.
“She tested negative again on a rapid antigen test, but a PCR test came back positive.
“The First Lady is double-vaccinated, twice boosted, and only experiencing mild symptoms.”
Her infection comes just under a month after Mr Biden himself contracted the virus.
The 79-year-old first contracted the virus on 21 July, when he was revealed to be experiencing mild symptoms.
He then isolated for six days at the White House while Ms Biden stayed at their house in Delaware.
Despite testing negative four days in a row, the president then tested positive on July 30 and was forced to isolate again until August 7.
His doctor said the unexpected positive test was the result of a “rebound” infection.
This, physician Dr Kevin O’Connor suggested, could have been due to Mr Biden taking Paxlovid, and antiviral medicine.
According to Ms Alexander, Ms Biden is now taking the same medication.
She added that Ms Biden “is currently staying at a private residence in South Carolina and will return home after she receives two consecutive negative COVID tests.”
The White House confirmed that Mr Biden has tested negative today, but is considered a close contact of the First Lady.
It added he will follow Centers for Disease Control and Prevention guidance and wear a mask indoors for 10 days, and be tested more frequently.
The president is scheduled to return to Washington, D.C. today to sign the Inflation Reduction Act, a new bill which will raise over $700 billion in government revenue over 10 years via new taxation, and spend over $430 billion to reduce carbon emissions and extend subsidies for health insurance.
It’s unclear if the first lady’s positive test will affect the president’s scheduled trip.