[CliffordK (OP)]

I was just thinking about HIV/AIDS. 
About 0.3% of all humans are immune.  Obviously it isn't transmitted easily, but what if it was?  The Flu in 1918 killed 10 to 20% of those infected, and a total of about 3-6% of the global population.  What if it was worse?

Say, there was a super-epidemic that would wipe out 99.9% of all people.  Assuming an even distribution.

A city of 100,000 would be reduced to about 100 individuals.
World population would fall from 7 Billion to 7 Million (same as estimate of 7,000 BC).

We are so tied to large industry, transportation, and trade.  But, that would likely collapse.

I can think of my response.  Move to a more fertile agricultural area.  Plant a mix of food crops and oil crops.  Try to collect as many cars, tires, tractors, and etc, as one could, and figure out how to protect them from the elements.  Spare parts would likely have to be scavenged, or fabricated from scratch. 

Hire a small group of people who's sole job was to protect and maintain the local university, and university library...  and preserve as much knowledge as possible. 

With effort and some sense of leadership (would we have it?)  We could survive. 

Would we be able to maintain and grow without reverting to technological development beyond, say 100 years ago?

What if it wasn't disease, but some kind of traumatic disaster?  Asteroid impact, Global Nuclear War, Sudden climate shift (warmer or cooler), etc?

Many apocalyptic movies show hoards of looters fighting among themselves, essentially only living on the remains of the past civilization without making anything new.  Would we be doomed to destroy the last vestiges of the previous civilization?

[Gordian Knot]

One answer, read William Forstchen's One Second After. It describes what happens to our society if a massive EMP attack hit the entire U.S. at once. Few people are affected, no buildings are damaged. No invasion, no change in global weather, no massive amounts of bodies decomposing everywhere.

Just everything with a computer chip goes dead. Which in our modern age, means just about everything but the kitchen table! The result is chilling to put it mildly.

[CliffordK (OP)]

One answer, read William Forstchen's One Second After. It describes what happens to our society if a massive EMP attack hit the entire U.S. at once. Few people are affected, no buildings are damaged. No invasion, no change in global weather, no massive amounts of bodies decomposing everywhere.

Interesting thoughts.
It doesn't have to be an attack.  Our sun is able to generate EMPs with solar flares.  One in 1989 knocked out the power grid for several thousand people in Canada.  What if a bigger one hits?

Could it knock out all the vehicles?  Communication?  Tractors?

What would happen if the food doesn't get to the markets?  What if the water stops flowing?  All without warning on a global scale.  There are many rivers I wouldn't want to drink out of.

It is hard to know what would happen.  I'm sure I could ration myself for a month, perhaps a couple of months with food (except when it gets down the need for another supply run), but so much is dependent on the continual flow of supplies.  Could they cease?

[graham.d]

It is just as well that we have paper books. At least much of the world's knowledge will be preserved. It would take a long time to rebuild the socio-economic infrastructure in order to get back to the current level of technology that the western world, and increasingly the rest of the world, depends upon. If you think what has happened in past times, it is the not that knowledge has been lost but it is that subsequent societies were not able to make use of it. It was centuries before the works of Ancient Greece were utilised and, in Europe, there was several hundred years in the "dark ages" post the fall of the Roman Empire.

[CliffordK (OP)]

It is just as well that we have paper books. At least much of the world's knowledge will be preserved.

Yes... 
And thus I would prioritize assigning a library/university curator.  The card catalog would be a mess as it hasn't been updated for decades in most libraries, if it still exists at all anymore, but it could be replaced.  Climate control would be an issue when attempting to preserve paper books for hundreds or thousands of years with minimal power.

Fortunately there would be multiple copies of important works around the globe.  But, perhaps one should consider the vulnerability of Electronic-Only copies of information, as the Wikipedia generation replaces Encyclopedia Britannica generation. 

Museums would be built... not to preserve the past, but rather to preserve the future.

[rosy]

It would probably depend on the nature and outcome of the resulting wars, but yes, the human race would survive, I think.

Of course, food would need to be the first priority.

For example in this country... we currently import food, but if we had a population 1/1000th of its current size it'd be pretty straightforward to grow enough food fairly soon.

Although modern farming technologies would probably have been lost, as they depend on assembly and supply chains for machinery (and chemical fertilizers/pest control etc.) the number of people to be fed would have crashed. It's possible to live on a more-or-less completely unrelieved diet of potatoes, which require little skill and relatively little labour to grow (provided you don't get blight), and there are other vegetables that could be grown for self-sufficiency if a large proportion of the population had died... especially as there'd be loads of land available to grow them on (and every house, and every other third-floor flat, has a book on the shelf about "feeding yourself from your allotment" or "how to grow veg", right?)

Then there's livestock... there'd be an awful lot of cows/sheep/pigs that were left with no-one to care for them. Lots of them would just die, but sheep are pretty low-maintenance and that's your meat ration sorted for the foreseeable.

Climate control would be an issue when attempting to preserve paper books for hundreds or thousands of years with minimal power.

Hundreds, let alone thousands of years wouldn't be an issue. We've got quite a lot of renewable energy plant already, and with the population slashed we certainly wouldn't need all the fossil fuels we currently burn (tho' we would lose cars, and tractors). Provided the computerised power grids weren't locked down entirely by passwords taken to the grave by the power company employees we should be able to get the grid back up within months. The telephone network would also need to be a priority.

Building new computers might mean collecting together the surviving employees of ARM, IBM, Microsoft, Google and the people who work in chip fabrication for companies I've never heard of (with translators as necessary, and as many patent databases as possible) and getting them to work together.

[Devilmunkey]

On a purely statistical note, 0.1% of the current (estimated) population of the world would be ~700,000 individuals.

Genetically this would be ample for for the continuation of Humans as a species.

The question of whether this number would be contained in a single population or as a collection of smaller aggregates throughout the world would obviously be dependant on what caused the loss of the other 99.9% of humanity.

[CliffordK (OP)]

On a purely statistical note, 0.1% of the current (estimated) population of the world would be ~700,000 individuals.

0.1% is the same as 1/1000.
7,000,000,000 (seven billion) / 1000  = 7,000,000 (seven million)

Did you misread it as 0.01%?

Genetically this would be ample for for the continuation of Humans as a species.

The question of whether this number would be contained in a single population or as a collection of smaller aggregates throughout the world would obviously be dependant on what caused the loss of the other 99.9% of humanity.

Yes,
I was thinking about this (along with Rosy's answer).
Pestilence could leave the infrastructure intact, just a small enough population that normal tasks could no longer be taken for granted.
War, or perhaps an asteroid strike, might both kill individuals, as well as destroying the infrastructure which would be much more damaging to the future.

One might be able to ignore an international infrastructure, but concentrate on what is available in one's own continent. 

Things, like the majority of cotton is grown on the other side of the country.  I don't even know if I could find cotton seeds locally.  I suppose it might be easier to grow sheep.  But, one would likely choose to maintain major roads, waterways, and domestic trade, especially for nonperishables where one might choose to an annual cross-country convoy for trade.

Local phone system, or interstate phones?
Without a good supply chain, the systems could be difficult to maintain, or to rebuild if badly damaged.
Perhaps one would see a revival of the postal service.

[Don_1]

Judging by the unbelievable lack of knowledge about food, I would think starvation would put paid to most of the initial survivors.


Q. Where does 'bacon' come from?
A. Tesco

[Devilmunkey]

I think the loss of a huge amount of specialist skill and knowledge would be a great problem. Areas such as agriculture and manufacturing would certainly be affected or indeed cease altogether in some cases. If general infrastructure still remained intact, the required opperational knowledge to run and maintain powerstations, oil rigs, refineries and such would certainly be lacking.

Communities would be forced to adapt to the local environment in terms of what food and materials they could produce (which in the area I live would be little more than sheep farming, possibly some quarrying of sandstone, granite and tin). There would probably be a new reliance on gathering of wild foods and materials and maybe a new market for items scavenged from old population centres.

I think perhaps one of greatest  issues would be the loss of medical expertise and supplies. Infant mortality would certainly rise, accompanied by a reduction in life expectancy. Lack of basics such as antibiotics would make even minor injuries potentially fatal. Also with the lack of any vaccination or control programs there would be a surge in re-emergant diseases, as the level of herd immunity in the population declines. Unclean water and poor sanitation would lead to epidemics of water bourne diseases such as cholera.

It would be a very difficult struggle for humanity.

(Oh and yes my bad on that calculation earlier. The decimal point will one day be my downfall)

[Nizzle]

I think, since electricity has become so crucial in our current society, that windmill generators,  hydroelectric power plants and other electricity generating structures that do not require resources to be kept running will become the nuclei for communities after the apocalypse.

[Sprool]

I think, since electricity has become so crucial in our current society, that windmill generators,  hydroelectric power plants and other electricity generating structures that do not require resources to be kept running will become the nuclei for communities after the apocalypse.

Surely if our 'current society' is put through such an apocalyptic change, then the old values abpout what is so important will no longer apply? If everything electrical ceases to function then wind farms and hydroelectrics will also have little value.

[CliffordK (OP)]

Depending on how it would happen, one would have to learn to redistribute the wealth of the dead, without devolving into complete anarchy, and still respect the rights of the living.

As long as the equipment could be maintained, one farmer could still feed 1000 people which would mean people could continue specialized tasks.  '

Many of the big hydroelectric installations should last 100 years with minimal maintenance, although the power distribution grids would require periodic maintenance which could overwhelm a "skeleton crew".  One might choose to relocate and rebuild some industry near the power generation facilities.

Perhaps the longevity of the race would depend on whether we have visionaries looking towards the future, or if everyone just chooses to fend for themselves, and live off of the past.

After all, if one could collect 1000 toasters, when would one have to make a new one?

[Donnah]

We need to hope that included in the surviving .1% are staff of nuclear facilities. 

http://en.wikipedia.org/wiki/List_of_nuclear_reactors

You might be as surprised as I was to see how many there are.