Variola virus, the agent of smallpox. Image courtesy Russell Kightley Media.
There has been a lot of tweeting today about how Smallpox Will Come Back From The Grave And Kill Us All: see here, here and here for lurid examples.
This is alarmism at its insidious best: shouting out a headline, based on flimsy evidence, that says “We’re all going to die!” or similar nonsense.
Really: this IS nonsense. Some corpses were found in the permafrost in Siberia, that MAY have had smallpox-like lesions on them, and from some of which which smallpox virus DNA could be recovered – presumably by PCR.
“Pithovirus sibericum”, from Jean-Michel Claverie and Chantal Abergel
I can believe you could get live anthrax: those spores are incredibly tough, and can last for many years in soil, let alone in ice. I could also believe that one could find live megaviruses – the so-called pitho- and molliviruses – in permafrost, because their putative hosts are unicellular protozoans and because they are also seriously stable.
But smallpox? The virus is probably not as stable as the megaviruses mentioned; it relies for infection on its structure, which has membranes integral to it – AND it infects people, who, when they die, don’t cool down very quickly, and whose cells release all sorts of nasty enzymes (lipases, proteases) as they die. Which could be expected to chew up most things, including poxviruses.
Oh, sure, poxviruses CAN survive for years at a pinch – in the form of dried secretions or scabs, which, because they are dehydrated and full of protein, tend to stabilise virus particles. This is how the old variolators and vaccinators (literally: people who used variola or “vaccine” to vaccinate against smallpox) used to preserve their inocula, when they weren’t using fresh material.
Melting tundra is not like that, I will note: bodies with intact virions in them will thaw and rot all over again, and that rotting will reduce what little virus there may be even further.
So I am not a believer in Death From The Permafrost!
And nor should you be. But it might not hurt for someone qualified to test whether or not there IS live virus in frozen samples, by culturing an extract?
ViroBlogy 