Jessica M. Vaughan is the director of policy studies at the Center for Immigration Studies.

The case of Thomas Eric Duncan, the Liberian man who brought Ebola to the United States, demonstrates how the erosion of effective immigration controls has put Americans at risk, and suggests further steps that must be taken to protect the public from international travelers who are a threat to public health.

Neither the U.S. government nor the airlines nor the Liberian government have effective measures to screen travelers for exposure.

Neither the U.S. government nor the airlines nor the Liberian government established effective measures to screen international travelers for exposure to Ebola. Duncan was apparently tested for fever and questioned by officials but did not disclose his contact with a woman who had recently died, suggesting that he knew he was at risk. Clearly it was folly to expect that we could rely on individuals to self-quarantine in these situations.

The total number of visas issued to citizens of Liberia, Guinea and Sierra Leone is not large relative to other countries. But it’s a large enough group to worry about. Based on State Department nonimmigrant visa issuance statistics, I estimate that there are about 5,000 people in Guinea, 5,000 people in Sierra Leone and 3,500 people in Liberia who possess visas to come to the United States today (or who could be in the U.S. right now). Additional steps need to be taken to protect our communities.

Our government must simply deny admission to any non-U.S. citizen who has been in the afflicted countries in the recent past, until the crisis is over. The most fundamental purpose of immigration controls is to protect our homeland, and our leaders must end their chronic reluctance to use them.



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