Why the first week matters

The next five to 10 days will be critical for President Donald Trump following his positive test for Covid-19. Doctors warn the illness can suddenly worsen after several days of relatively mild symptoms.

That’s particularly true for patients with two of the biggest risk factors for serious and even life-threatening complications of the disease: obesity and older age. Trump, 74, with a body mass index of 30.5, qualifying him as obese, fits both criteria.

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“I’m worried,” Dr. Vin Gupta, a pulmonologist and affiliate assistant professor at UW Medicine in Seattle, said Friday on “TODAY.”

“I’ve cared for several patients with that double whammy,” Gupta said. “If they become sick, if they are symptomatic, they can escalate quickly to needing ICU care.”

What’s more, research has shown men tend to fare worse with Covid-19 than women.

A White House official said the president is experiencing “mild symptoms,” though it is unclear what those symptoms are. A letter from the White House physician confirming the positive test results for both Trump and the first lady Melania Trump said the two are “well at this time.” It is also unknown when the president was infected.

That knowledge would be key in directing how his physicians will monitor and potentially treat him.

“I try to get as good a handle as I can on when my patient contracted the virus,” said Dr. Pieter Cohen, a physician with the Cambridge Health Alliance Respiratory Clinic near Boston. “If the president was exposed to the coronavirus less than five days ago, then this is very early in the infection.”

Cohen and other doctors who have been caring for Covid-19 patients for months say the infection has two key parts: an initial phase with minimal to no symptoms, followed, for some, by a more severe phase.

“Then there is the later, more concerning, days of illness, usually days four through eight but can be later as well,” Cohen said. “That is when serious complications, often beginning with difficult breathing, tend to begin.”

Dr. Josh Denson, a pulmonary medicine and critical care physician at the Tulane Medical Center in New Orleans, said it’s rare for a person to become very sick within the first few days of infection.

“This could drag out,” Denson said. “If he recovers, it won’t be for a week or so. But I’ve had some patients get critically ill more than 2 to 3 weeks after the initial infection.”

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The Centers for Disease Control and Prevention’s guidelines indicate the president should be in isolation for at least 10 days, and should remain in a “sick room or area and away from other people.”

It is likely that during that time, Trump’s oxygen levels will be carefully monitored using a device called a pulse oximeter, Gupta said. Monitoring oxygen levels is critical as they can plummet in people with Covid-19, even if they don’t feel sick.

“His physicians will be checking his oxygen level. Is he short of breath? Does he have a fever? Does he have chills or a cough? Extreme vigilance here is warranted,” he added.

Doctors may treat any symptoms the president may develop, but there is no known treatment proven to prevent Covid-19 patients from moving from the initial stage of illness to the second, potentially more dangerous stage, Cohen said.

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Peter Alexander contributed.

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