The death of Thomas Duncan in Dallas on Oct. 8 has provided another turn in the debate over containing Ebola. Infected with the virus, Duncan had flown from Liberia to Brussels to Washington to Dallas. That revelation provoked a blunt response from a few American politicians: Ban flights from West Africa. Texas Representative Ted Poe, a Republican, has written to the Centers for Disease Control and Prevention asking it to recommend travel restrictions. In a letter to Michael Huerta, the head of the Federal Aviation Administration, Texas Republican Senator Ted Cruz wrote that “it is imperative the FAA take every possible precaution in preventing additional cases from arriving in the United States.” Representative Alan Grayson, a Democrat from Florida, has called for a 90-day ban on travel from Ebola-affected countries to the U.S.
The White House is resisting those calls, and that’s the right thing to do. Restricting travel to and from the affected region will have little impact on the already minimal risk to Americans from the Ebola virus while further worsening the situation in Liberia, Guinea, and Sierra Leone. The history of the global fight against infection has demonstrated that we shouldn’t raise the drawbridge or run away but fight the disease wherever we find it.
Travel restrictions have a long history as a tool against spreading infections. Quarantine was first used against the plague bacillus in 14th century Europe. At the time, quarantine was pretty much the only potentially effective public-health strategy. (Neither prayer nor pogroms had the desired impact.) The Black Death still exists—there were four cases of human infection in the U.S. in 2012—but we now have a vaccine against the disease. It can be treated with antibiotics, and sanitary and housing conditions in the 21st century are considerably better than in Europe in the 1300s.
We don’t have a vaccine against Ebola nor a fully developed cure. But like the plague, the disease is an unlikely candidate for epidemic status in the U.S. or elsewhere in the developed world. The only way to contract Ebola is for the bodily fluids of someone who’s exhibiting symptoms to come into contact with your soft tissues—the eyes or mouth, for example. In the worst of circumstances, the average Ebola victim infects one or two other people, compared with 10 or more who can be infected by someone with measles.
Isolation of people with symptoms, rather than quarantine of an entire population, can stop an epidemic. That’s why all previous Ebola outbreaks have sputtered, leaving the world with no reported cases in 2010, for example. The U.S. has top-notch isolation facilities, and health authorities have considerable experience of “contact tracing,” or finding all the people a victim has spent time with since he began exhibiting symptoms and checking that they don’t have the disease.
Controlling illness by quarantine of an entire country or region involves trade-offs. It’s always theoretically possible to avoid risk by completely cutting yourself off from contact, but then you’ll be alone. We take some risk of infection through contact because the benefits of that contact outweigh the risks. Trade is worth one-quarter of U.S. gross domestic product. People want to travel to see family and friends, visit places, work, or invest. We think all that is worth the price of somewhat increased risks of illness.
Consider our approach to dealing with illnesses that are far more threatening than Ebola. In an average year, more than 23,000 deaths in America are associated with influenza. But this toll isn’t enough for us to shut the borders in an attempt to keep influenza at bay. The idea that we could completely seal off the U.S. from the rest of the world is laughable—at best we might delay a disease from arriving by a few days or weeks. When it comes to the flu, we’re not even willing to take considerably more targeted and effective measures, such as banning kids from school if they haven’t received the vaccine or providing shots for free at pharmacies.
Most of the economic harm from epidemics comes from reduced commerce and travel. A 2006 World Bank estimate (PDF) of the costs of a flu pandemic suggested it could reduce global gross domestic product by $1.5 trillion. One-third of that amount was accounted for by death, illness, and absenteeism. But two-thirds came from the cost of people trying to keep away from infection, mainly by staying in place. The World Bank has estimated the cost to Liberia of the Ebola outbreak to be equal to more than 3 percent of its GDP. Add in a formal travel ban to West Africa, and the impact on some of the world’s poorest economies could be catastrophic.
A travel ban would also be counterproductive for the U.S., making the likely global impact of the epidemic far worse. The three West African countries affected need outside support, including the hundreds of medical volunteers who have stepped forward from countries as disparate as the U.K. and Cuba. Banning flights into West Africa will delay the arival of help when every day is critical in preventing an explosion of cases. Banning commercial flights out of the countries will deter people from volunteering to work in the region.
With greater support, the three countries bearing the brunt of the epidemic can fight back against Ebola. Neighboring Nigeria and Senegal have shown that they can detect Ebola, isolate victims, trace their contacts, and shut down the disease. And although Liberia, Guinea, and Sierra Leone have desperately fragile and underfunded health systems made worse by Ebola’s toll, their programs aren’t completely dysfunctional. All three have wiped out major infections: smallpox, polio, and Guinea worm.
The lesson of the world’s efforts to stop other deadly diseases is that if we want to reduce our exposure to dangerous pathogens, we have to fight them where they are and when they emerge. It wasn’t until the third decade of our knowledge about AIDS that a significant global effort to respond was made, notably through President George W. Bush’s 2003 announcement of the President’s Emergency Plan for AIDS Relief. Despite the late start, the initiative currently supports treatments for 6.7 million people with HIV worldwide, and the number of new infections dropped by one-quarter from 2001 to 2011. We’ve also seen incredible progress against a range of infectious diseases over the past 20 years because of the rollout of vaccinations and other interventions in even the poorest countries.
This global progress is the most powerful weapon we have in permanently reducing the risk and cost of infectious disease in the U.S. The eradication of smallpox has saved more than 40 million lives (PDF), and it also saves about $2 billion a year in vaccination and hospital expenditures in the U.S. alone—an impressive return for a program that cost about $300 million.
We live in a global disease pool. In the end, once a disease begins to spread, there’s no escaping an infection, whether it first appears in Africa, Asia, or the U.S. Travel bans are less effective than hiding under a rock and considerably more costly. To battle continuing epidemics and potential pandemics, we need strong health and surveillance systems in every country and research and development not only for the diseases of the rich (such as cancer and heart conditions) but also for the infections of the poor. Hitting emerging disease threats early and where they emerge is far less costly in terms of lives and financing than trying to play catch-up once they have spread.