We Need Testing and Trust — Not Travel Bans, Says Epidemiologist

Part of the Series

Despair and Disparity: The Uneven Burdens of COVID-19

We are all facing the consequences of the Trump administration’s many failures in responding to the coronavirus pandemic, from the disastrously low number of tests that have been administered to identify and treat those with the virus to the misleading presidential statements and absence of national leadership in implementing aggressive and timely public health measures for physical distancing aimed at slowing the spread of the virus.

Predictably, Trump and his supporters claim that he is doing a tremendous job, and they point to the travel ban on flights from China issued by the White House as proof that the administration has been on top of this crisis from the beginning. Last week, Trump imposed another travel ban on Europe, despite the fact that the virus is already present in all 50 states of the U.S.

Framing COVID-19 as a foreign menace that can be blocked through border controls sits in well with the anti-immigrant bigotry at the heart of the Republican Party. Trump’s continuing framing of this global pandemic as a “Chinese virus” has already fueled a spate of anti-Asian violence across the country, and it threatens to undermine the global cooperation among governments, scientists and peoples that will be necessary to contain its ultimate death toll.

Derek Cummings is an infectious disease epidemiologist who has worked around the world studying the spread of MERS, dengue, novel forms of influenza, and has spent considerable time studying the 1918 influenza pandemic. In this interview, conducted on March 13, Cummings discusses travel bans and the elements of an effective public health response.

Danny Katch: When you hear politicians referring to a “foreign virus” or “Chinese coronavirus,” do you think the language of xenophobia creeping into this can have negative public health effects?

Derek Cummings: When I hear “foreign virus,” it seems like a nonsensical term. These viruses infect us all, and this is a pandemic as described by the World Health Organization (WHO). Different societies are going to play different roles over the course of this pandemic. Early on, China was the source of cases to other countries because they had the majority of cases. They seem to be controlling transmission so it’s possible later on that most cases will be in the rest of the world and they’ll be worried about introduction from the rest of the world into China. You never know what role you’re going to play in this outbreak and the best policy is for us all to work together.

It’s tricky for a surveillance system to transition. If an outbreak starts outside of the country, most people coming into the country will have acquired it outside. But that [pattern] changes, and your testing needs to transition before that starts to happen, and prioritize testing in the community.

In recent days there has been discussion about how China and South Korea have been seemingly more effective in reducing the virus’s spread. Can you distinguish targeted quarantines and the internal measures some countries have taken from broad travel bans targeting entire countries and continents?

The term isolation refers to a person that you know to be infected: you isolate them so that they don’t transmit to others. For larger groups of people that you think have had exposure and might or might not be infected but are at risk, you quarantine. That’s just a difference in terms. The term “cordon sanitaire” is being used to describe [these measures] going out from bigger groups to a city-wide level — putting guards at all the exits from Wuhan [for example] — and minimizing travel out of that affected area to others.

I think the most effective responses to this outbreak have identified infected individuals by testing and isolating them. Testing people earlier in their infection and identifying a larger proportion of them before they can do more transmission has been a key response in other settings that have slowed transmission.

What we can’t know is how much of Wuhan or South Korea’s success in curtailing transmission is attributable to that, and how much of a role social distancing of their general population — irrespective of whether they are infected — has played as well. Right now we need to throw everything at this virus and we’ll figure out later what was most effective and make adjustments. But I think the key thing is the testing and isolation.

There was an endogenous movement to reduce travel between the rest of the world and China — tons of people cancelled their flights because of the perceived risk. There were also travel bans put in place. It’s difficult to know how much travel reduction happened because people just decided they weren’t going to go to China because of the risk compared to how many of those people cancelled because it was imposed on them by the government. Which of those were most important and how do they compare to these other public health measures? I’m not sure.

Public health experts are generally critical of travel bans as a response to epidemics. Since you think we should be “throwing everything we can” at this pandemic, how would you respond to the argument that even [with]Trump’s recently announced travel ban on Europe, it can’t hurt?

We have thousands of infections here in the U.S. From those thousands of infections, we’re expecting them to give rise to thousands more. Typically, in an outbreak, once you have a certain number of cases, the importations are part of the noise of the transmission process here. So the feeling in the community right now is that the U.S. has a lot more infections than have been detected because testing has been slow, and the new importations that would come from Europe would be small in comparison.

If we found out that at this point 1 in 20 or 1 in 100 of the cases we would expect next week in the U.S. would be from importations from Europe, at what number do we start to assess the trade-off of all the possible negatives from that travel ban? What happens if we can’t get the materials for testing? What happens if we’ve eroded the relationship and the communication between the WHO and these other European health agencies in sharing information and data and that has an impact on the epidemic that is much larger than the impact of that 1 percent next week?

I am concerned that the travel ban will slow down the movement of resources between Europe and the U.S. A number of reagents — materials necessary to run the test to detect coronavirus — are made by European companies. There are already concerns that we’ll have shortages of those laboratory materials to run the tests, and these materials are consumables that need to be replenished all the time to keep running these tests.

That’s a very concrete concern that you might interrupt that flow, but I also think there are subtler concerns about the continued collaboration between public health entities in Europe and the United States. The entire globe is facing this threat — there are going to be innovations that may matter for this outbreak, and we don’t want to slow those down; we want them to be shared across countries as freely as possible.

Could travel bans also reinforce the idea that this virus is not already in our communities but is coming from people who are “different”? That’s dangerous socially and politically, but could it also hurt efforts to limit the pandemic by misleading people to not take precautions around familiar people in their community?

Yes, I think travel bans emphasize that you think most transmissions are happening among people going outside of the state, and communicate to people that they aren’t at risk of coronavirus if they haven’t travelled. That [mistaken] approach means that it’s going to take longer to detect community spread.

A lot of public health responses are built on trust. You need the public to trust you and the information you’re giving them because you need them to engage in these socially disruptive control measures that we’re asking people to engage in — shutting down schools, asking people to socially distance themselves, to minimize interactions with other people.

One other critical element is for people to trust us to come forward for testing if they’re sick. Let alone other concerns, purely as it relates to the effectiveness of a public health response, stigmatization and discrimination reduce that trust and lead to people not coming forward for testing and treatment. Anything that degrades the trust between the public health responders and the community degrades the public health response.

Making a community trust your responses requires supporting them so that you’re not just saying, “Hey you’re quarantined and you’re on your own.” We need to support communities that we’re asking to take these measures to contain the epidemic as much as we can. That’s through resources, communication and by building trust.

You are a scholar of the 1918 influenza that the rest of us are suddenly more familiar with. What lesson should people learn from that history?

There are many unhelpful comparisons between the flu and this coronavirus that have minimized the impact of this coronavirus outbreak. But one important thing that’s been discussed about the pandemic of 1918 is that there’s evidence that people’s responses to socially distance themselves were able to reduce the transmission of influenza.

Influenza transmits much more effectively than this SARS coronavirus. We would not be considering at this point the possibility of containment that WHO is still advocating for if this had the characteristics of an influenza virus. But even in that outbreak of influenza, a much harder pathogen to contain, people changed their behaviors – they stayed at home and governments cancelled events and schools — and transmission decreased.

Many communities in the Midwest and California saw news reports from the East coast, where dramatic outbreaks occurred in Philadelphia, New York City, and all over. [As a result] these communities had two peaks of transmission: people changed their behaviors and it reduced transmission. Then cases went down and people started going back out of their homes — they need to go to work, needed food — and the disease came back. But that still flattened the curve — made the peak number of cases in any week much smaller. That means that you have more health care resources to devote to anybody in any week, so you improve survival rates and reduced total number of deaths in those communities.

So that gives us hope, and the response in China and South Korea and other places tells us that we can respond to this outbreak and slow down transmission. But it’s going to take some social disruption. Better for us to do that proactively in these early stages than for us to wait and let the virus create the social disruption on its terms.

This interview has been lightly edited for clarity.