Why no Ebola vaccine yet?

Just developing the vaccines to test in monkeys was a grueling, decades-long process that has killed scores of macaques since the 1990s. American researchers almost gave up. "No one thought you could protect with a vaccine, because [Ebola] was so aggressive," saysNancy Sullivan, a top official at the U.S. National Institute of Allergy and Infectious Diseases. The insidious nature of the Ebola virus has been among the hurdles in the long, elusive quest to develop an effective vaccine and treatment for one of the most dangerous viruses the world has ever known. Progress also has been slowed by the hazards that come with researching it and-perhaps more than anything else-by the economic and moral questions of focusing on a pathogen that until the current outbreak had infected fewer than 2,400 people worldwide. (Related: "As Ebola's Spread Continues, Key Questions and Answers.") At a time when malaria kills 600,000 people a year, tuberculosis kills 1.3 million, and AIDS 1.6 million, Ebola was a lower priority for many health officials, National Geographic reports. But now the Ebola virus is exploding in West Africa, and its reach is moving well beyond there-to Europe and the United States. It has infected at least 2,400 people in West Africa during the past three weeks alone, and more than 4,000 deaths there have been linked to the virus since the outbreak began late last year. (Related: "Doctors and Nurses Risk Everything to Fight Ebola in West Africa.") With news over the weekend that the virus had been transmitted within the United States for the first time-to a nurse who had treated a Liberian with the disease at a Dallas hospital-the need for a vaccine and better drugs suddenly has hit home with many Americans. National Institutes of Health Director Francis Collins has put the politics of the issue into sharp relief, saying in an interview with the Huffington Post that a vaccine and treatments would have been ready now if it hadn't been for federal budget cuts to basic research. "It's not like we suddenly woke up and thought, 'Oh my gosh, we should have something ready here,' " Collins said. If funding hadn't been slipping over the past decade, he said, "we would have been a year or two ahead of where we are, which would have made all the difference." Now the effort to produce a vaccine, or a more effective treatment, has become a race against a virus that typically has killed 70 percent of its victims. The World Health Organization warned Tuesday that Guinea, Liberia, and Sierra Leone could see as many as 10,000 new Ebola cases per week by year's end. In the coming months, as caregivers, politicians, and armies struggle to deal with the spiraling number of cases, a handful of vaccines and treatments will be tested on humans for the first time. If one or more works and can be produced in adequate quantities, the course of the epidemic might be altered and hundreds of thousands of lives saved. And it would rewrite the story of the next Ebola epidemic or stop the story from being written. (Related: "Every Newly Emerging Disease Like Ebola Begins With a Mystery.") But if the vaccines and drugs fail in people, the world could be faced with the enduring casualties and mass fear that are the stuff of science fiction-or history. Details also at