Mini advent calendar of Xrisks: Pandemics

The deathrates from infectious diseases follow a power law with a very low exponent. In layman’s terms: there is a reasonable possibility for a plague with an absolutely huge casualty rate.

Have you taken into account the cutting criticisms from Cosma on the bogosity of many power-law claims?

Do you have any examples of a species rendered extinct by a plague in nature? As far as I know, there are no known natural evolutionary paths to produce a super-plague like this:

anything that combined the deadliness and incubation period of AIDS with the transmissibility of the common cold.

Some people are genetically immune to AIDS, such transmission would rapidly select for that resistance in humans, while selection on the virus would reduce lethality (losing hosts). Also, HIV has a long incubation period because it is not replicating and killing cells at the rapid rate of the common cold, the tradeoffs here are real.

We’ve had close calls in the past: the black death killed around half the population of Europe, while Spanish Influenza infected 27% of all humans and killed one in ten of those, mostly healthy young adults.

People were suffering from malnutrition, poor sanitation, lack of broad-spectrum antibiotics and antivirals, lack of vaccination tech (to deal with both the flu and simultaneous or opportunistic infections). The Spanish Flu did its damage disproportionately to poor countries, while rich countries got by with a small fraction of the fatality rate.

Today the world is much richer, better fed, and otherwise protected than in 1918-1919.

The FHI survey of global catastrophic risks conference attendees assigned a median probability of 0.05% to a natural pandemic killing off humanity. I would assign a higher existential risk than direct extinction risk, on the basis that social collapse might be irrecoverable, but this is a small x-risk compared to artificial diseases.

All the characteristics of an ultimately deadly infection already exist in the wild: anything that combined the deadliness and incubation period of AIDS with the transmissibility of the common cold.

Correct me if I'm wrong, but aren't there very good reasons why those qualities don't overlap? Analogously it would be literally true to say that we'd be at great risk if threaten by an animal with the killing abilities of a tiger and the reproduction speed and numbers of ants, but such a thing isn't biologically possible.

Also worth to mention that humans created ideal bioreactor for creating new viruses - and that is pigs. Pigs could ill human, avian and animal flu viruses and recombinate them. Population of pigs is growing with economic growth and now is around one billion.

Another "bioreactor" is widespread use of antibiotics which lead to creating of new superbags.

Growing human population is also contribute to the chances of appearance of new superbug.

But in fact I a little bit dissapointed by this 4th risks as it seems similar to biohazards mentioned earlier. It could be not easy to distingush natural pandemic and bioweapon usage.

Well, it does look that killing a big species is like freezing a body to absolute zero.

I am ready to buy that 0%-10% killers are distributed according to the promised power law, if you buy that reducing human population from X to kX costs -log k. Note that this doesn't alter your observed power law at all.

Why this? Because you have to be stronger than random resistances (due to genetics, lifestyle, health conditions etc.) present in different slices in populations.

Also, any virus will evolve while it infects a billion humans; there is a pressure to spread better and leave host alive.

And long incubation period cuts both ways — either you are stealth for years, or you are spread by air next week.

I agree with most of what was said here, except that, well.... I don't think it has the potential to actually cause humans to go extinct, or even to simply collapse civilization :-/ Even if a pandemic killed off 75 % of all humans, I have an unprovable feeling civilization would be able to soldier on. This is substantiated by a couple of observations; nearly all human knowledge has multiple backups (pandemics don't kill libraries), so we wouldn't have to reinvent science from scratch. Plus,remaining population would have access to all the material goods of the dead (including canned goods, long lasting food, etc. Which wouldn't be nearly enough to sustain human population for more than a month, but which would give time for people to pick up a book on farming or some such).

On the other hand, it is virtually guaranteed that a pandemic WILL happen (I define pandemic as something that shows up on the news a lot and causes some panic. Kill ratios depend on a case by case basis), given our interconnectedness which is frankly unprecedented in human history (i.e. Microbes, viruses and germs never had airplanes before 1902)