Doctor: Virus’ impact will take a week or two

President Donald Trump and first lady Melania Trump revealed early Friday morning that they have tested positive for COVID-19, the disease caused by the coronavirus.

All the same rules about isolating and the risks of the virus apply to them, said Dr. Thomas Inglesby, director of Johns Hopkins’ Center for Health Security and a leading voice on the pandemic.

Inglesby answered some questions about the coming days. Here they are, edited slightly for clarity — and updated since reports Trump was taken to Walter Reed Medical Center with information from a tweet by Inglesby:

What might it mean that Trump was taken to the hospital?

The fact that the President is going to Walter Reed may mean his symptoms are now concerning enough to his physician team for him to be hospitalized or that he is going to get a specific treatment, or that they just want him there to be closely monitored as a precaution.

Given this disease can be mild in nature or can be very serious, and that it is possible to move from one to the other quickly, it will be important for the public and Congress to be closely and transparently informed of how the President’s illness is evolving.

What can we expect to hear about Trump’s health and when?

The president will get the best care in the country. Part of that care will be ensuring he does not need hospitalization because he is short of breath. That’s the top priority for them now.

It will be some time before we know the outcome. The fact that he has symptoms is an obvious concern because it means he has clinical illness. Flu-like symptoms can progress to something else. All serious illnesses began as mild illness. It could be week or two before people have more serious symptoms.

Are the president’s age, weight and underlying conditions factors?

Unfortunately, we know people in his age bracket are at much higher risk of negative outcomes. And people of his body mass index are more likely to have serious health outcomes.

He also has underlying cardiac risk factors, based on what’s publicly reported. His calcium score from his CT scan [the amount of plaque observed] is higher than it should be.

There are a number of reasons he’s at higher risk. Many people in that category do well, but there is increased risk of not doing well.

How much risk is there to the people who have been around him?

There will need to be a contact investigation into who has been exposed. Generally the way that works is when someone is symptomatic, and reports are that President Trump has mild symptoms, you go back two days before the onset of those symptoms to understand who may have been exposed.

Anyone who has been in close contact with him in that time is considered a contact. The CDC says that is anyone in contact for 15 minutes and within 6 feet of him. So if he had symptoms yesterday, go back two days from then and test and quarantine them for two weeks.

He had many things on his schedule. Looking at the news, it looks like many people traveled with the president in the last few days, many without masks and in close proximity. They’ll all have to be sorted out with interviews.

What if they test negative initially, as Vice President Mike Pence has reportedly tested?

Even if someone tests negative they could still become positive over time. The virus can take a while to incubate. You can be negative, negative, negative and then positive. It gets less likely over time. Most become positive within six days, and beyond that it’s less likely. But this is why the CDC says to quarantine for two weeks. [Quarantines are for those exposed and isolation is for those who have tested positive.]

Vice President [Joe] Biden needs to be tested as well. It’ll be the judgment of public health authorities if he needs to be considered a contact. He does not fit the classic definition because he was at a distance from the president during the debate. Though, there were a lot of loud voices, and that spreads the virus.

What are your takeaways from this news?

The virus doesn’t defer to people who have more resources or a specific profession. It’s an equal-opportunity virus, and we’re all at risk, except possibly those infected and recovered. It really underscores the message that we all need to take this seriously. The pandemic has not turned the corner. We’re still in the middle of it, and we need to follow public health guidelines. What does that mean going forward? Vigilance, especially given the cold weather. Some things we’re still able to do outdoors, which is safer, but some things will be coming indoors. It’s really important to remember the risk of large gatherings. They really increase the risk of transmission, and we should do what we can to avoid that.

The flu season is coming. Hopefully we look like the Southern Hemisphere, which had a mild season. But everyone was distancing and wearing masks. I don’t know if that will be the case here. It’s really important to keep at it. And the flu vaccine is more important than ever as we wait for a coronavirus vaccine.