Penicillin?

Actually, those jumping pathogens are frequently harmless or only mildly irritating to their original hosts. They become virulent either because they're new to the environment [the human body, that is], and so evade the natural controls - rather like rabbits in Australia, for a macroscopic example - or as part of the process of adapting to the new environment.

What's worse, much of our microbial baggage consists of _formerly_ virulent bugs that have learned that coexistence is the more viable option [killing your host isn't really a paying proposition]. That is known to be subject to change without notice. E. coli is the classic example of a bacterium that can become deadly when circumstances change - and moving to Safehold is a serious change of circumstances. And no, the planners are not going to simply disinfect the colonists' plumbing. That's a good way to end up with a planet full of dead colonists - not only are the resident bugs often essential for normal operation, in ways that are only now beginning to come to light, but many of our passengers have tucked themselves away in niches that can't be cleaned out without killing us, and, even more importantly, doing so would simply open the way for colonisation by anything at destination that was even remotely capable of surviving the conditions.

And since there is evidence for the cycle from virulence to non-virulence, or back, taking as little as 5 years...

cralkhi wrote:

Tenshinai wrote:
Eh, why do you think seasonal influensa vaccines keep having to be remade so often? Sometimes even more than once a year?

Because new strains can and do appear all the time.

Well, sure, but these are mutations of a virus that is already causing human disease.

Totally new diseases jumping to humans generally come from pathogens of other mammals... occasionally from birds.

So if the Operation Ark people had removed all pathogens from the people and livestock they brought... that's an entirely different picture.

Maybe something could evolve from previously harmless human bacteria... but there still shouldn't be much.

Louis R wrote:Actually, those jumping pathogens are frequently harmless or only mildly irritating to their original hosts. They become virulent either because they're new to the environment [the human body, that is], and so evade the natural controls - rather like rabbits in Australia, for a macroscopic example - or as part of the process of adapting to the new environment.

Even so, though, many major human diseases originated as animal -> human jumps (smallpox, many influenza strains, Ebola, etc.)

IIRC supposedly this is why many European diseases devastated Native Americans, but American diseases didn't devastate Europe - the Native Americans had fewer diseases due to fewer domestic animals.

And no, the planners are not going to simply disinfect the colonists' plumbing. That's a good way to end up with a planet full of dead colonists - not only are the resident bugs often essential for normal operation, in ways that are only now beginning to come to light, but many of our passengers have tucked themselves away in niches that can't be cleaned out without killing us,

I wasn't suggesting total disinfection -- certainly humans need a functional symbiotic microbial flora. Merely the removal of all pathogens.

and, even more importantly, doing so would simply open the way for colonisation by anything at destination that was even remotely capable of surviving the conditions.

That doesn't strike me as plausible. Safehold life should be sufficiently bio-chemically different from Terran for that transition to be very unlikely.

And since there is evidence for the cycle from virulence to non-virulence, or back, taking as little as 5 years...

I'm sure it might have happened a couple of times on Safehold, but I just don't see it as likely that Safehold would have a disease environment sufficient to make public health have the degree of significance it seems to have.

I expect that within a generation or two that most babies on Safehold will be "vaccinated" with nannites, which will cure any and all existing and new diseases.

I doubt that most of the population will understand what they're actually being injected with, but since those nannites will work like a charm, nobody is going to complain! (Except the Luddites who still cling to the CoGA, even though it will have been revealed as a complete
fraud by then.)

Happily their reluctance to accept being "vaccinated" will speed their demise...

You misunderstood - you _can't_ eliminate only the pathogens. Every single critter in your gut is capable of inducing illness under the right conditions as it stands now, many of them appear to have been major pathogens that have become domesticated, and _all_ of them are quite capable of evolving into pathogens in a very few generations under the correct stimulus [and what that might be, we have no idea and probably never will]. That's just the gut. The uro-genital and respiratory tracts, mouth, ears and nasal passages, skin and even your eyeballs all harbour colonies of all sorts that can only be completely eliminated by destroying the organs in question. And that few generations? that's _microbial_ generations that can be as short as hours, not human generations.

And that doesn't count an assortment of cryptoinfections, where the pathogen is hiding in apparently normal tissues. Again, what triggers a reversion to virulence is not at all clear, and there aren't always clear markers to suggest even the possibility that this individual is a carrier. How do you plan to eliminate those without eliminating the person? And every person who ever came into contact with them, or into close proximity, or even, for all we know, passed through the same country as they did?

As for native bugs, I can guarantee that if we can eat Safehold organisms - and the textev is that we can - at least some of them can eat us. Nor is it at all necessary for them to be able to do so, as far as that goes, as long as we're eating native foods. Vibrio cholerae has killed hundreds of millions without ever, technically, entering any of its victims' bodies. It just sets up in the small intestine, digests all the goodies it finds there and just happens to spew out a toxin that kills all the cells tasked with pumping water and nutrients across the epithelium into the bloodstream, triggering massive diarrhea, dehydration and consequent death. You may be willing to bet that there's nothing on Safehold that can pull the same trick; I'm not even prepared to bet that there's nothing that could do it if you never touched a native foodstuff. We _might_ be safe from native virii, but bacteria and parasites will be able to survive on us at least well enough to make people very, very ill. In fact, the dying off as they failed to thrive for very long could be the worst part of it.

cralkhi wrote:

Louis R wrote:Actually, those jumping pathogens are frequently harmless or only mildly irritating to their original hosts. They become virulent either because they're new to the environment [the human body, that is], and so evade the natural controls - rather like rabbits in Australia, for a macroscopic example - or as part of the process of adapting to the new environment.

Even so, though, many major human diseases originated as animal -> human jumps (smallpox, many influenza strains, Ebola, etc.)

IIRC supposedly this is why many European diseases devastated Native Americans, but American diseases didn't devastate Europe - the Native Americans had fewer diseases due to fewer domestic animals.

And no, the planners are not going to simply disinfect the colonists' plumbing. That's a good way to end up with a planet full of dead colonists - not only are the resident bugs often essential for normal operation, in ways that are only now beginning to come to light, but many of our passengers have tucked themselves away in niches that can't be cleaned out without killing us,

I wasn't suggesting total disinfection -- certainly humans need a functional symbiotic microbial flora. Merely the removal of all pathogens.

and, even more importantly, doing so would simply open the way for colonisation by anything at destination that was even remotely capable of surviving the conditions.

That doesn't strike me as plausible. Safehold life should be sufficiently bio-chemically different from Terran for that transition to be very unlikely.

And since there is evidence for the cycle from virulence to non-virulence, or back, taking as little as 5 years...

I'm sure it might have happened a couple of times on Safehold, but I just don't see it as likely that Safehold would have a disease environment sufficient to make public health have the degree of significance it seems to have.