Viruses in the ice

Comments on Cecil's Columns/Staff Reports
#1

Original question

One downside of being locked up in the ice for thousands of years, if you’re a virus, is that your host’s immune system will go on evolving without you. Yes, it might lose the ability to quickly recognise the virus (and so be more susceptible to infection) but the pressure to actively lose this recognition ability is normally tiny.

The flip side to this is that the most successful viruses are probably the ones we never find out about because they have evolved alongside us to just sit there hidden in our cells, spreading slowly but not doing anything destructive enough to kill the host (or cause the host to kill itself). A previously benign virus might lose this ability simply because it was recognised as foreign. I doubt this would turn into a pandemic though.

NB: I’m not a virologist so if anyone wants to dispute this please do so!

#2

some are just dormant

#3

When I read about the giant virus, I immediately thought of something the size of Godzilla attacking Manhattan.

“Damnit General, you can’t bomb it with penicillin, it’s a virus! Our only hope is to find five million gallons of chicken soup, or the whole city is doomed.”

I also thought of that Star Trek episode where the Enterprise was attacked by a giant space amoeba. Wonder how big the virus that preys on that one is.

#4

The article made me think about smallpox - most of us are as vulnerable to the disease as the native Americans prior to the arrival of the Europeans. Is it possible for someone to have died from smallpox, be buried in the tundra (in the mean-time we wiped-out smallpox in the wild), then when thawed, that corpse could spread the disease back to humans again? :eek:

#5

Snowthx - yes, I imagine so, but we wiped it out before with a vaccine and I see no reason we couldn’t do so again (I’m not sure the vaccine was contemporaneous with what happened to the native Americans but if it was I very much doubt there would have been much political appetite for vaccinating them at the time).

I’m interested that you say we’ve no natural immunity - my understanding is that, while our immune systems may not have been exposed to it as they would have been a few hundred years ago - and thus won’t have any antibodies ready to go, they will have retained at least some of the increased potential to produce the right antibodies if exposed to the virus. This is because the “major histocompatibility complex” or MHC is a set of genes which determine which antibodies we can potentially make, and this will have come under selection pressure in our forebears’ time while it would not have done in a population never exposed to smallpox.

I do remember getting quite confused at around this point in immunology though, and I also remember the MHC does something weird which means it effectively mutates faster than the rest our our genotype.

#6

“circumstantial evidence suggests we’ve already had a few small-scale viral infections due to germs liberated by thawing”

I’d like to know more.

#7

I’m guessing Cecil didn’t comment on background radiation whacking the bejeezuz out of long term stored DNA for scientific reasons not yet suitable for release to the teeming masses.

In our pitiful state of ignorance, sadly we’ll continue to believe natural decay of Potassium 40 would severely degrade any extant DNA over long periods. Instead the master has pointed out possible ‘oxidation reactions’ as the degradation mechanism over the time period and avoided totally mentioning Potassium 40 (or even Thorium or Uranium) due to reasons well known to himself.

#8

JezzaOz - Aren’t the two interlinked? The oxidation is produced by free oxide radicals which will themselves be created in part by background radiation (in fact, in cold conditions, I doubt there will be much else creating them).

#9

I assumed Cecil was referring to radiation when he said “Theoretical considerations suggest no genetic material can survive intact beyond 2 or 3 million years.”

#10

Small pox is a virus and could last quite a while, but it’s spread through skin contact. I would imagine if a corpse is exposed by a tundra thaw, there won’t be too many people willing to make physical contact with it. If one is found, for a variety of reasons, it’ll be treated with great care in case of contact not only with smallpox, but a variety of diseases.

However, you make a good point. We haven’t had small pox outbreaks in over five generations in the west, and whatever genetic immunity we may have had (let alone exposure developed immunity) would be quite low. A few of us had small pox vaccinations when we were young, but I believe it was stopped about 30 years ago when small pox was extinguished in public.

Of course, the U.S. and Russia both have live small pox virus in various laboratories for scientific purposes, so it’s not entirely extinct.

#11

They exhumed members of the Franklin Expedition who had been buried in the permafrost for 140 years. This was documented in a 1988 episode of Nova called Buried in Ice. You can decide if they used “great care.”