Via The Guardian: Ebola isn’t the big one. So what is? And are we ready for it? Excerpt:
Ebola is very unlikely to become the next Black Death. But that doesn’t mean something else won’t. Even with modern medicine, we haven’t rid ourselves of pandemics; indeed, they have sprung up far more recently than 1918. HIV/AIDS is the most recent truly devastating pandemic – and H5N1 Avian Flu was even more widespread, though less deadly. Ebola is very high on severity, and very low in terms of mode of transmission
There are many nightmare scenarios, according to Robert G Webster, chair of the virology division at St Jude Children’s Research Hospital. “Just imagine if the Ebola outbreak in West Africa was transmitted by aerosol. If flu was just as lethal. If H5N1 [Avian Flu] was as lethal in humans as it is in chickens – and studies have shown that it only takes about 3 mutations to make it highly lethal. It’s not out of the realms of possibility.”
Fraser said that pandemics are extremely difficult to predict because they all start from a random event: a pathogen crossing to humans from another species.
“The initial change, the transition, that’s where the pathogen sets in motion its change of transmission,” he said. “There are outbreaks of all kinds of strange viruses that come from contact between animals and humans; one in a million will give rise to a starting pandemic.”
That moment, he said, when the virus is learning to propagate in a new kind of host, is when much of its genetic mutation happens – after that, its evolution is much slower. The real danger is a brand new virus, or a hybrid of several (HIV is a combination of four viruses), rather than an evolution of one which, like Ebola, is already known to humans.
Ran Balicer, director of the infectious diseases track in the public health department of Ben Gurion university in Israel, thinks that the most likely candidate for another pandemic is a strain of influenza.
“It is always on the horizon, and is a devastating scenario,” he said. “It has a good possibility of manifesting in our lifetime; there have been 3 major pandemics, and a mild one three years ago – which doesn’t reduce the possibility of a pandemic happening.”