TED日本語 - セス・バークレー: ワクチンの開発を執拗に阻むある事実

The child's symptoms begin with mild fever, headache, muscle pains, followed by vomiting and diarrhea, then bleeding from the mouth, nose and gums. Death follows in the form of organ failure from low blood pressure.

Sounds familiar? If you're thinking this is Ebola, actually, in this case, it's not. It's an extreme form of dengue fever, a mosquito-born disease which also does not have an effective therapy or a vaccine, and kills 22,000 people each year. That is actually twice the number of people that have been killed by Ebola in the nearly four decades that we've known about it. As for measles, so much in the news recently, the death toll is actually tenfold higher. Yet for the last year, it has been Ebola that has stolen all of the headlines and the fear.

Clearly, there is something deeply rooted about it, something which scares us and fascinates us more than other diseases. But what is it, exactly? Well, it's hard to acquire Ebola, but if you do, the risk of a horrible death is high. Why? Because right now, we don't have any effective therapy or vaccine available.

And so, that's the clue. We may have it someday. So we rightfully fear Ebola, because it doesn't kill as many people as other diseases. In fact, it's much less transmissible than viruses such as flu or measles. We fear Ebola because of the fact that it kills us and we can't treat it. We fear the certain inevitability that comes with Ebola. Ebola has this inevitability that seems to defy modern medical science.

But wait a second, why is that? We've known about Ebola since 1976. We've known what it's capable of. We've had ample opportunity to study it in the 24 outbreaks that have occurred. And in fact, we've actually had vaccine candidates available now for more than a decade. Why is that those vaccines are just going into clinical trials now?

This goes to the fundamental problem we have with vaccine development for infectious diseases. It goes something like this: The people most at risk for these diseases are also the ones least able to pay for vaccines. This leaves little in the way of market incentives for manufacturers to develop vaccines, unless there are large numbers of people who are at risk in wealthy countries. It's simply too commercially risky.

As for Ebola, there is absolutely no market at all, so the only reason we have two vaccines in late-stage clinical trials now, is actually because of a somewhat misguided fear. Ebola was relatively ignored until September 11 and the anthrax attacks, when all of a sudden, people perceived Ebola as, potentially, a bioterrorism weapon.

Why is it that the Ebola vaccine wasn't fully developed at this point? Well, partially, because it was really difficult -- or thought to be difficult -- to weaponize the virus, but mainly because of the financial risk in developing it. And this is really the point. The sad reality is, we develop vaccines not based upon the risk the pathogen poses to people, but on how economically risky it is to develop these vaccines. Vaccine development is expensive and complicated. It can cost hundreds of millions of dollars to take even a well-known antigen and turn it into a viable vaccine.

Fortunately for diseases like Ebola, there are things we can do to remove some of these barriers. The first is to recognize when there's a complete market failure. In that case, if we want vaccines, we have to provide incentives or some type of subsidy. We also need to do a better job at being able to figure out which are the diseases that most threaten us. By creating capabilities within countries, we then create the ability for those countries to create epidemiological and laboratory networks which are capable of collecting and categorizing these pathogens. The data from that then can be used to understand the geographic and genetic diversity, which then can be used to help us understand how these are being changed immunologically, and what type of reactions they promote.

So these are the things that can be done, but to do this, if we want to deal with a complete market failure, we have to change the way we view and prevent infectious diseases. We have to stop waiting until we see evidence of a disease becoming a global threat before we consider it as one. So, for Ebola, the paranoid fear of an infectious disease, followed by a few cases transported to wealthy countries, led the global community to come together, and with the work of dedicated vaccine companies, we now have these: Two Ebola vaccines in efficacy trials in the Ebola countries --

(Applause)

and a pipeline of vaccines that are following behind.

Every year, we spend billions of dollars, keeping a fleet of nuclear submarines permanently patrolling the oceans to protect us from a threat that almost certainly will never happen. And yet, we spend virtually nothing to prevent something as tangible and evolutionarily certain as epidemic infectious diseases. And make no mistake about it -- it's not a question of "if," but "when." These bugs are going to continue to evolve and they're going to threaten the world. And vaccines are our best defense. So if we want to be able to prevent epidemics like Ebola, we need to take on the risk of investing in vaccine development and in stockpile creation. And we need to view this, then, as the ultimate deterrent -- something we make sure is available, but at the same time, praying we never have to use it.

Thank you.

(Applause)