Illness on Generation ship

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Illness on Generation ship

Postby caters on April 9th, 2018, 1:00 am 

With 44000 people for genetic diversity reasons, it is inevitable that some will be ill. Now the types of illness allowed would differ.

Take viruses for instance. A cold virus like this rhinovirus:
Image
Would be no big deal. It would just cause a cold.

Ebola on the other hand would be a huge deal because of those diagnosed, half of them die. Yes you heard me right, 50% death rate. And with there being a lot of sex going on regularly and the likelihood that someone will touch blood or urine being high, especially in children, this would spread widely and even if just 1 person had Ebola, there would be a massive die off over time. Reproduction rate would start high but as more die, the reproduction rate will drop until it is lower than the 50% death rate(in other words when teens and older comprise less than 50% of the population). Once that happens, the whole population is guaranteed to die off.

So while this might mean needing eggs and sperm of healthy people and artificial wombs as a backup, it doesn't mean that no people should be on it.

In fact, I think the worst viral infections that would be allowed are skin infections that go dormant(like chickenpox) and severe respiratory infections(pneumonia for instance). Any worse and the death rate would be too high.

Fungal is another story. A lot of fungal infections and I mean, a lot, are mild. Skin infections, vaginal yeast infections, both of those types of fungal infections are mild. Most severe fungal infections occur in people with weakened immune systems or lung disease or in those fighting another infection like a bacteria or a virus. So death rate from fungi is low, so low that I don't think fungal diseases should be restricted by severity at all. Fungal infections usually spread through direct contact or sex in the case of a vaginal yeast infection. However, sexually transmitted yeast is most likely going to give a male a UTI which can easily be treated with lots of fluids to wash away what is causing the infection. Yeast infections are also the most likely to be resistant to antifungal treatment.

So far we have this on the spectrum:

Image

Now come the big guns. Bacteria. Just 1 group of bacteria species can cause all these illnesses:

  • Strep Throat
  • Impetigo
  • Scarlet fever(which is common after untreated strep throat)
  • Pneumonia
  • Toxic Shock Syndrome
  • Flesh Eating Disease

And these complications after the infection is over:

  • Acute Rheumatic fever
  • Rheumatic heart disease
  • Post-streptococcal Glomerulonephritis

So yeah, Bacteria would be in the grey area. If 1 bacterial species can cause a mild illness in 1 person but a very severe illness in another, should bacterial illness be allowed at all? I honestly think it should, but only some bacteria. Streptococci would be one of those allowed types of bacteria. Food borne bacteria such as salmonella would likely also be allowed since salmonellosis would most likely result in gastroenteritis. Some subspecies of salmonella can cause typhoid fever or paratyphiod fever though. These are the life-threatening types of salmonella. But like I said, most salmonella would only cause gastroenteritis. In fact lots of different bacteria can cause gastroenteritis.

Parasites are another gray area. You have 2 types of parasites, heleminths, such as tapeworms, and protozoa, such as plasmodium falciparum. Malaria is parasitic but it causes hemolytic anemia and periodic fevers. Intestinal parasites on the other hand will most likely only cause diarrhea or sometimes, no symptoms at all.

So far we have this on the spectrum:

Image

There is only 1 pathogen left. That is prions. These are not organisms nor are they cellular parasites(viruses are in a sense cellular parasites because they invade cells to cause an infection and can't multiply without the cells), they are simply proteins that are misfolded which cause normal proteins to become misfolded. The only way I could see getting rid of prions before infection is a lot of protease supplements on top of normal digestive enzymes to ensure the proteins are broken down. This would not be ideal because it is quite possible that these proteases would themselves cause intestinal inflammation. So this would be in the red area, absolutely not allowed, not even in 1 person.

So here is the full spectrum:

Image

However, if I were to go through a list of every infectious illness and decide whether or not it is allowed, should I have a death rate limit? Is there a point at which pregnancy rate and more importantly birth rate, can't overcome the death rate from infection assuming an average death rate of 8 per 1000 per year from other causes?

So is there a point at which death rate from infection would cause something like this to happen to the population:

Image

In other words exponential decay once the birth rate lowers to below the death rate?

Assuming about a fourth of the women are in the fertile window per week and a sex ratio of 1:1, this means with every pairing, there is at most a 25% pregnancy rate per week in the population. But of course, those that didn't get pregnant before would try again and so it would increase to be more than 50% of the women within a month that get pregnant, say something like 80%. Of those that get pregnant say 20% miscarry and 1% end up with a stillbirth. This would mean a 79% birth rate in pregnant women which would mean a 31.6% birth rate in the population overall. And this 31.6% would be every 2 years, except that 2% of breastfeeding women will get pregnant before their periods and the chance of getting pregnant increases with every passing period until after 2 years, when breastfeeding stops, it gets back to the 80% rate. Sort of like a slow but exponential growth.

Main reason for allowing illness? Immune systems in their prime and prevention of these:

  • Autoimmune disease(without illness, it is more likely the immune system will see something harmless as foreign)
  • Allergies(same thing, just not against human tissue)
  • Weak immune system(this would be the worst, this could mean major die off from minor illness)
caters
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