Cheryl Benard is a former senior analyst with the RAND Corporation and has written about health systems in post-conflict environments.

Like thousands of Americans and Europeans scrambling to get to the United States before the travel ban went into effect and flights were canceled, I flew back to the United States from Vienna on Friday. Arriving at Dulles International Airport via London, I encountered a case study in how to spread a pandemic.

I had thought I was lucky to get one of the last seats home. And I was confident, because Dulles had been identified by the administration as one of the handful of U.S. airports equipped to test arriving passengers and admit or quarantine them accordingly, that I would find a rigorous protocol in place upon arrival. Obviously, the administration would not take such a momentous step without solid preparation.

I could not have been more wrong. Upon landing, I spent three hours in a jammed immigration hall trying to decide which analogy fit better: the ignorant Middle Ages during the plague years or the most chaotic airport in the least developed country.

The pictures you may have seen only begin to capture the chaos. There was no attempt to enable social distancing; we were packed closely together. Two giant queues of people — one for U.S. citizens and green-card holders and one for foreign nationals — wound their way through the cavernous hall. I counted and came up with approximately 450 people in each section, for a total of just under a thousand. Many were coughing, sneezing and looking unwell.

When I inched closer to the front, I could see that a scant six immigration desks were in service. Two additional desks to the left had less traffic. These are ordinarily for people in wheelchairs; now, the wheelchairs were mixed in with the rest. When I asked a security guard about the other lines, he told me they were for people with a confirmed corona diagnosis. There was no separation for this group — no plastic sheets, not even a bit of distance. When your line snaked to the left, you were inches away from the infected.

I recently flew to Qatar for a meeting. Immediately upon disembarking, passengers walked past a temperature measuring device to identify those with a fever, so they could be segregated out before entering public areas. Dulles had no such plan. Instead, after the agent examined your passport, he pointed a thermometer device at your forehead. By that time, you would have spent three hours in close contact with hundreds of other people. Even the way the lines were organized, snaking around, might have been designed to ensure that one sick person would expose the maximum number of others.

Some of the agents were asking people to use the fingerprint screen — all fingers, then the thumbs. Mine didn’t, but I watched the adjoining one and was astounded to see that the screen was not wiped, sprayed or in any way sanitized between individuals, or indeed at all during the hour I had it in my line of sight. My agent asked me how I felt (the true answer would have been upset by your colossal ineptitude) and if I had been to China or Italy. (I had not.)

That was it. No instruction to maintain a two-week self-quarantine. No phone number to call if I felt symptoms — standard in Europe for several weeks. After being immersed in our three-hour virus incubator, we were unleashed on the American public, free to mingle. This had to be going on all day and further into the night, as flights kept landing and the immigration hall kept filling with new passengers.

There was a better way. The travel ban should not have been announced until the airports were prepared. People should have been held on planes and disembarked in small groups, led past temperature-measuring devices and then admitted planeload by planeload, to reduce mingling. Dulles has two sets of buses to take people from plane to the terminal, for Washington arrivals and transit passengers. They could have been repurposed for U.S. citizens and foreign nationals. An immigration officer could have processed people while still on the bus.

Need I mention that a containment area for sick passengers might be advisable? Or telling people what to do if they feel sick? The day after I arrived, my doctor told me that tests were not available even for people with symptoms, and if I developed any, I should go to the hospital. If that’s not the official policy, that has not been communicated even to our doctors, let alone our citizens.

When he announced the travel ban, President Trump described it as an effort to keep out foreigners who might bring the virus to our shores. Instead, his actions caused an abrupt and dramatic influx of potentially infected people, with no attempt made to manage or control it. Dulles is a terrible, and terrifying, microcosm of a disaster magnified by incompetence.

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