U.S. President Joe Biden has tested positive for COVID yet againafter taking Paxlovidin just what a White House physician Saturday called an incident of rebound.
Bidenwho initially tested positive July 21, following a week of traveling over the Middle Easttested negative for the herpes virus on Tuesday night and again on Wednesday morning of the past week, when he ended his isolation.
He additionally tested negative Thursday and Friday mornings before testing positive again Saturday morning, in accordance with a letter from presidential physician Dr. Kevin OConnor to White House Press Secretary Karine Jean-Pierre, obtained and posted to Twitter by way of a Reuters correspondent.
On Saturday the president said via Twitter he would go back to isolation even though hes not experiencing new symptoms.
Folks, today I tested positive for COVID again, he wrote. Ive got no symptoms, but I will isolate for the safety of everybody around me. Im still at the job, and you will be back on the highway soon.
Rebound COVID, Paxlovid and otherwise
Biden was treated with the COVID-19 antiviral Paxlovid your day he was diagnosed, in accordance with multiple news outlets. Its a pill approved for treatment of COVID-19 in high-risk adults just like the elderly, having received emergency-use authorization from the U.S. Food and Drug Administration.
However the drug is well known for rebound cases, described by the U.S. Centers for Disease Control and Prevention as a short return of symptoms.
Such rebounds, however, can occur with or without Paxlovid, Andy Pekosz, virologist at the Johns Hopkins Bloomberg School of Public Health, told Fortune on Saturday.
Its not unusual for people to get a positive test a couple of days following a negative test with COVID-19, he said. What I believe folks are more centered on nowadays is if this can be a Paxlovid rebound, meaning hell have a recurrence of the herpes virus.
As the U.S. Centers for Disease Control and Prevention says that COVID rebounds are rare, they may be more prevalent than we realize, as most people with COVID stop testing once they get a negative result.
The White House does a good job of testing people every day, Pekosz said. Theyre more likely to catch a few of these rare things with that degree of frequency.
The presidents rebound positive test was an antigen, or rapid, test, OConnor wrote. Antigen tests are superior with regards to gauging whether someone is shedding live virus and, therefore, infectious, he said, adding a positive antigen test is most likely reasonable to return into isolation.
Faucis Paxlovid rebound
When identified as having COVID in June, chief presidential medical adviser Dr. Anthony Fauci was prescribed the antiviral because of his advanced age, which put him at greater risk for a severe outcome from COVID, despite being fully vaccinated and twice boosted.
Fauci later said he previously experienced a Paxlovid rebound.
WHEN I finished the five days of Paxlovid, I reverted to negative on an antigen test for three days in a row, Fauci, 81, said during a meeting atForeign Policys Global Health Forum, Bloombergreported. And on the fourth day, merely to be sure, I tested myself again.
I reverted back again to positive.
Fauci later told theNY Timesthat Paxlovid kept him from the hospital and stopped his infection from becoming more serious initially, saying, Paxlovid did what it had been likely to do.
Fauci began another span of Paxlovid when symptoms emerged much worse compared to the first go-around, he said. IN-MAY the CDC issued a health advisory about such rebounds, saying there is no evidence that additional treatment is necessary for rebound cases.
In June,Pfizer, which manufactures Paxlovid, announced that it could stop adding new participants to an effort of the drug among COVID patients at low threat of hospitalization and death. The analysis didn’t demonstrate that the drug reduced symptoms, or hospitalizations and deaths, in a statistically significant way, in accordance with Bloomberg.
But Paxlovid could be undeservedly gaining a negative rap, Pekosz cautioned.
Ill still indicate the truth that its employed in terms of keeping people out from the hospitalthats it is important at this time, he said, adding that it could have to be retooled to raised address Omicron subvariants.
Just how long to quarantine?
The CDC currently advises COVID-positive individuals to quarantine for five days before time for normal life (and masking in public areas for yet another five days). The recommended isolation time was 10 days until December, once the federal health agency halved it.
But there isn’t data to aid five days or anything shorter than 10 days, Amy Barczak, your physician at the Massachusetts General Hospital Infectious Disease Division,recently toldNature.
Some scientists havequestioned the explanationbehind the policy because the CDC introduced it late this past year. And todaycriticshave significantly more data to back up their claims: Viral shedding may appear beyond 10 days in even healthy, vaccinated adults, in accordance with a preprint out of Londonpublished this month.
Some scientists advise that folks stop quarantining only one time they test negative using at-home tests, instead of counting on the CDCs five-day rule alone.
Biden did so, however, testing negative at five and six days after infection before ending his isolation. The White House hadsaid thatBiden would beat the CDCs five-day guidance and wait until he tested negative before time for public life.
He apparently wasnt expecting a rebound.
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