The White House should now be ground zero for a huge contact tracing operation

Contact tracing has been poor in the US. But Trump’s positive coronavirus test shows why it’s so important.

With President Donald Trump’s positive coronavirus test, the White House is now ground zero for the most closely watched contact tracing exercise of the Covid-19 pandemic in the US.

The speculation started as soon as Trump announced his diagnosis in the wee hours of Friday morning. Could he have exposed Democratic presidential nominee Joe Biden at Tuesday night’s debate? What about his fundraiser in New Jersey on Thursday night? He’s been meeting with Supreme Court nominee Amy Coney Barrett — what if she contracted the virus? Not to mention Barrett has been meeting with senators in the lead-up to her first confirmation hearing. (She has initially tested negative as of Friday morning.) Nobody can even be sure how Trump got the virus either. Did he contract it from his aide Hope Hicks, whose positive test was reported shortly before the president’s? Or did they both get infected from another, shared source?

How big could the cluster of infections around Trump grow? The only way to figure it out is contact tracing: identifying who has been in close contact with the president since he became contagious, and asking them to quarantine to prevent Covid-19 from spreading to others, and to get tested themselves. We also aren’t sure what kinds of tests the Trump administration is using, and that makes a difference in figuring out who else might be exposed.

Testing for Covid-19, tracing people who may have been exposed, and getting them to isolate is the backbone of an effective coronavirus response. It’s also a program that the US has largely failed to execute effectively — but which is now of utmost importance to the continued health of our nation’s leaders and those around them.

Ashish K. Jha, dean of the Brown University School of Public Health, laid out in a brief Twitter thread what should happen now, and the challenges that will make contact tracing difficult even at the White House.

This is the first difficulty: People who have contracted the coronavirus and are contagious still might not show symptoms for several days. As Muge Cevik, a virologist at the University of St. Andrews, laid out on Twitter recently, people with Covid-19 generally start to become more infectious in the two days before their symptoms start and then for a week afterward.

So Jha recommended: “Everyone who has been near the President at least from Saturday on needs to be identified.” But that is, as he acknowledged, easier said than done.

Contact tracing, in non-pandemic times, is typically concentrated on sexually transmitted diseases. Generally speaking, people know who they’ve had sexual contact with; so while these can be sensitive discussions, there is not much confusion about who may have been exposed to HIV or syphilis.

But an airborne virus like Covid-19 is much more difficult to trace. The general rule of thumb, public health workers have told me previously, is you want to identify anybody who has been within 6 feet of an infected person for a period of 15 minutes or more.

In addition to his usual meetings with advisers, Trump has been keeping up a busy public schedule. He hosted military families at the White House on Sunday. He was at the debate in Cleveland, Ohio, on Tuesday. He traveled to Minnesota on Wednesday for a campaign rally. He attended a campaign fundraiser in New Jersey on Thursday even after the White House learned of Hick’s positive Covid-19 test. New Jersey Gov. Phil Murphy is urging anybody who attended that event to get themselves tested and self-quarantine in the meantime.

The people who spend a lot of time around Trump may be at a higher risk if they refuse to wear a mask, as Jha pointed out.

So this work of testing, tracing, and isolating is already underway, because the president and senior government leaders being exposed to a deadly pathogen is rightfully seen as a national emergency. This is the right response after learning a person who is in contact with a lot of people has contracted the coronavirus.

But the US has also struggled to implement a test-trace-isolate program more broadly, despite strong expert consensus that it’s the best way to get the pandemic under control.

NPR reported last month that only seven states likely had the contact tracing workforce needed to effectively surveil their Covid-19 outbreaks. The US started the pandemic with about 2,000 public health workers who specialized in contact tracing; experts think 100,000 or more would be necessary to track the coronavirus. The federal government has largely been absent in helping state and local health agencies scale up those capabilities.

“Contact tracing has been mostly ignored at the federal level, and states have been left to prioritize as they see fit,” Joshua Michaud at the Kaiser Family Foundation told me over the summer. “Which means that some have done more and others have done much less.”

The other problem is the US is testing too little, and the virus is too widespread for contact tracing. Widespread testing is necessary to identify all of the people who have contracted Covid-19, so their contacts can also be notified. But more than half of states have a positive test rate above 5 percent, suggesting they are not doing enough testing relevant to the size of their outbreak.

And regardless, community spread means contact tracing has limited value. The goal of contact tracing is to stamp out new outbreaks before they start, but more than half of states have infection rates that experts already consider to be too high.

Covid Exit Strategy, led by a consortium of public health experts, estimates that only 11 states have the necessary workforce and a contained enough outbreak for contract tracing to be possible.

Countries like Germany and South Korea have kept their coronavirus outbreaks under relative control because of the strength of their test-trace-isolate programs. The US never built up its capacity.

But its importance is now more clear than ever — not only for protecting the people around President Trump, but for getting Covid-19 under control for everybody else, too.

Help keep Vox free for all

Millions turn to Vox each month to understand what’s happening in the news, from the coronavirus crisis to a racial reckoning to what is, quite possibly, the most consequential presidential election of our lifetimes. Our mission has never been more vital than it is in this moment: to empower you through understanding. But our distinctive brand of explanatory journalism takes resources. Even when the economy and the news advertising market recovers, your support will be a critical part of sustaining our resource-intensive work. If you have already contributed, thank you. If you haven’t, please consider helping everyone make sense of an increasingly chaotic world: Contribute today from as little as $3.