Time traveling immune systems

ScumLord

If a modern human from a city like London or New York went back 2000 years to a city like Rome, would the evolved immune system of the modern person make them almost immune to any disease or bacterial attack that would be doing the rounds in those cities?

Cities have always been hotbeds for all kinds of bacterias, they say someone living in a city will have a better immune system than someone from the country because they simply have more exposure to more bacteria than someone in the country would have.

We're seeing evolution of single cell life forms in our lifetime. Bacteria might have evolved a lot over the course of 2000 years. Our ancestors would have been the ones that survived many of the big outbreaks like the plague, so I'm guessing the modern human would have a better arsenal to fight ancient bacteria.

So, would a modern immune system have the solution to any problems ancient bacteria present based on it's previous experience with the modern version? Or would the ancient bacteria be more like brand new problems that a modern human wouldn't have any answers for due to the amount of time that's passed?

sbsquarepants

The opposite I would say - we've sanitised our immune systems to the point of non existence.

Capt'n Midnight

For some things our genetics provide resistance, we have the the worlds highest rates of Cystic Fibrosis, perhaps as a side effect of cholera resistance. There ain't no such thing as a free lunch.

For pretty much everything else each individuals immune system has to learn what's normal and what's not.

We still need vaccines to provide clues for this learning. If we had a superior immune system then people wouldn't still be suffering and dying from mumps, measles, polio , whooping cough, meningitis and other totally preventable diseases. It's looking like kids playing outdoors , getting cuts and colds and eating dirt is a sort of 'vaccination'


There's the probability that not challenging our immune system may actually lead it to 'find' something else to do , and auto immune diseases really, really suck when it comes to effective treatments.

Manach

Looking at from a historical development view point, we are the survivors of uncounted centuries of biological attacks. Hence there is an inbuilt level of immunity present in the time-traveller. As well, if one compares the skeleton remains present from the period of the Roman Empire with that of the modern physical make up, the modern person is more fit, robust and healtier. Finally, from I remember on reading new histories of the Spanish conquests of South America the level of biological patagoens from old to new world and their impact while still a factor, has now not been held as a major factor in the collapse in the Mesoamerican empires.
Thus, time travel away just remember to bring back some gifts for us.

Capt'n Midnight

ScumLord wrote: »

If a modern human from a city like London or New York went back 2000 years to a city like Rome, would the evolved immune system of the modern person make them almost immune to any disease or bacterial attack that would be doing the rounds in those cities?

The "evolved system of the modern person" can't even handle the tap water in Sligo / Galway a lot of the time, never mind the stuff in poorer parts of the world or what you'd get in the past before water treatment plants.

We live in a golden age of public health.

The Romans were big into lead acetate as a sweetener for wine. Roll the clock back a bit and you'll live in an era where flour and hence bread was frequently adulterated with any white substance they could get their hands on. Good luck getting your evolved immune system to handle mercury, lead, copper, chromium, iron and arsenic compounds

Hassall's work showed that adulteration was the rule rather than the exception and that adulterated articles were often sold as genuine.

Zillah

Capt'n Midnight wrote: »

Good luck getting your evolved immune system to handle mercury, lead, copper, chromium, iron and arsenic compounds

What on Earth do you think any of that has to do with the immune system? It fights pathogens, not toxins. Our bodies tackle poisons in a range of different ways depending on the poison.

And the Romans weren't any more resistant to those poisons than we are, they were getting lead poisoning from their water system just the same as you or I would, they often just didn't live long enough for it to matter.


I would be shocked if we weren't highly resistant supermen by ancient standards. Our DNA is the product of thousands of years of high intensity natural selection, we've been drastically upgraded via vaccines, and the nutritional quality we've enjoyed our whole lives would be a dream to 99% of the people alive back then. I did my fair share of rolling around in mud as a kid, there are very few people that grew up in ultra sanitised lab conditions.

Capt'n Midnight

Zillah wrote: »

What on Earth do you think any of that has to do with the immune system? It fights pathogens, not toxins. Our bodies tackle poisons in a range of different ways depending on the poison.

And the Romans weren't any more resistant to those poisons than we are, they were getting lead poisoning from their water system just the same as you or I would, they often just didn't live long enough for it to matter.

Just pointing out that even if a time traveller had a wonderful immune system (they don't) they'd still be stuffed if they tried the local food and drink.

I would be shocked if we weren't highly resistant supermen by ancient standards. Our DNA is the product of thousands of years of high intensity natural selection, we've been drastically upgraded via vaccines, and the nutritional quality we've enjoyed our whole lives would be a dream to 99% of the people alive back then. I did my fair share of rolling around in mud as a kid, there are very few people that grew up in ultra sanitised lab conditions.

Compared to poorer parts of the planet we live in ultra sanitised lab conditions. We throw out a third of our food because we deem it unfit to eat. That's way higher than other parts of the world, where stuff like sell by date would be aspirational, where EU food standards are aspirational.

Also we don't have the same selective pressures as previous generations where childhood deaths from now preventable diseases were horrendous.


If DNA upgrades worked in the way you think then over 300,000,000 people wouldn't have died of Smallpox in the last century. That's massive selective pressure given that the global population at the start of that century was only 2 billion.

There've been ZERO deaths since the 1970's.

ScumLord

Capt'n Midnight wrote: »

Compared to poorer parts of the planet we live in ultra sanitised lab conditions.

We may like to think we do but I don't know if we actually do. Cities are supposedly hotbeds of activity for bacteria. While places like our homes and public toilets are cleaned daily there's everywhere else to pick up diseases. Swabs taken in New york showed there's bacteria there they didn't even know existed. Over all our cities are cleaner, I don't think it's a case of them being sterile though, more a case of we're controlling their populations so they don't create a tipping point where they've a big enough population to cause real problems to people. But we would be in contact with all these bacteria on a daily basis, we are interacting with them.


So basically you're saying that bacteria and our immune systems wouldn't have changed that much in the last 2000 years? If we went back 200 years we'd essentially be fighting the same diseases with the same immune system?

Akrasia

The only reason we don't die from infections at the same rate as people in medieval europe, is because we have a modern medical system and antibiotics.

If a westerner from 2015 went back to 15th century Europe, the only real advantages he would have would be that he would know to wash his hands after touching a corpse, and wouldn't be so keen on any of the poisons that passed for medicines back then.

The immune system needs to learn how to fight each pathogen on a case by case basis. Children who are breastfed get a bit of a boost by sharing antibodies with their mother, but after that, we're on out own. This pre-natal and early childhood exposure to viruses and bacteria explains why people tend to be more immune to infections that are endemic in their community, but are much more likely to get infected if they travel and get exposed to viruses and bacteria that they have never been exposed to before. Simple viruses like the herpes simplex virus can be very debilitating to children the first time they are exposed to it, but subsequent exposures result in very mild symptoms

Vaccines don't confer inter-generational immunity which is a shame because we're starting to see the re-emergence of viruses like measels and mumps amongst the credulous sectors of the community who think vaccines are evil.

ScumLord

So our immune system starts from scratch at birth? I always thought you got a basic system and immunities passed down to you.

But going back to the example of someone from New York city going back to say Rome year zero. That person from New York would have grown up in contact with diseases and bacteria from all over the planet. No matter how clean his home is, once he goes into the underground he's subjected to things unique to the city and from cities all over the world. New York would be a real crossroads for all kinds of single celled life forms.

What he is subjected too would be evolved from the ancient bacterias around 2000 years ago. Would it not be like the first time Europeans went to the Americas? Europeans had immunities built up from living in their dirty cities subjected to bacterias from all over europe, Africa and the middle east that they passed onto American populations with devastating results. There don't seem to be many stories of Europeans dying at anywhere near the same rate from American diseases.

Capt'n Midnight

ScumLord wrote: »

Would it not be like the first time Europeans went to the Americas? Europeans had immunities built up from living in their dirty cities subjected to bacterias from all over europe, Africa and the middle east that they passed onto American populations with devastating results. There don't seem to be many stories of Europeans dying at anywhere near the same rate from American diseases.

One theory about syphilis is that Martín Alonso Pinzón, one of the captains on Columbus' voyage of discovery to America, brought it back.

Depending on who you believe up to one third of the population of Europe died from it. Even up the to the introduction of effective treatments last century it was killing off people in the US at the same rate as AIDS was at it's worst.

Akrasia

ScumLord wrote: »

So our immune system starts from scratch at birth? I always thought you got a basic system and immunities passed down to you.

Our genes can make us more or less vulnerable to certain kinds of infections, different people have different immune response to the same stimulis, this is inherited from your parents, but the actual antibodies are not. The reason why this is important is because sometimes, the virus or infection is only life threatening because it provokes too strong of an immune response for example, triggering a Cytokine storm http://en.wikipedia.org/wiki/Cytokine_storm, so people with the 'strongest' immune systems are more vulnerable to these kinds of illnesses (Spanish flu) but more would be less prone to other more common infections.

But going back to the example of someone from New York city going back to say Rome year zero. That person from New York would have grown up in contact with diseases and bacteria from all over the planet. No matter how clean his home is, once he goes into the underground he's subjected to things unique to the city and from cities all over the world. New York would be a real crossroads for all kinds of single celled life forms.

What he is subjected too would be evolved from the ancient bacterias around 2000 years ago. Would it not be like the first time Europeans went to the Americas? Europeans had immunities built up from living in their dirty cities subjected to bacterias from all over europe, Africa and the middle east that they passed onto American populations with devastating results. There don't seem to be many stories of Europeans dying at anywhere near the same rate from American diseases.

The bacteria and viruses that affect humans are in an arms race against the human immune system. They are constantly evolving and developing methods to evade detection in our bodies. Viruses in particular can evolve responses to vaccines within months of their development. It is unlikely that the many of strains of viruses and bacteria that existed in Europe 2000 years ago would be recognised by the immune system of a 21st century person even if he/she had immunity to the 21st century equivalent of this pathogen.

Geniass

Akrasia wrote: »

The bacteria and viruses that affect humans are in an arms race against the human immune system. They are constantly evolving and developing methods to evade detection in our bodies. Viruses in particular can evolve responses to vaccines within months of their development. It is unlikely that the many of strains of viruses and bacteria that existed in Europe 2000 years ago would be recognised by the immune system of a 21st century person even if he/she had immunity to the 21st century equivalent of this pathogen.

Was just going to add something similar to this. TB being a good example - whereas we thought this had been close to being eradicated it has mutated and is now more virulent.

If a modern person went back to ancient Rome they'd be in serious trouble as they'd have possibly less accommodation to the exact pathogens present at that time.

evolving_doors

I remember seeing a recent documentary showing a strong correlation between parisites (like ring worm or tapeworm I think!) and auto immune difficulties. They were citing the low incidences of chrons, asthma and a few others in under developed countries. I think that because we had eradicated such parisites that it triggered adverse auto immune responses in some people, there was also some mention of introducing parisites as a form of therapy!!
Helmintic therapy or something like that. Im not advocating a miracle 'cure' or anything but the tv program seemed to have the research to back it up. Can anyone remember it? they also followed a family and how the 'good' bacteria on the skin differed compared to who left the house more often.

From that point of view I dont think that all the 'good stuff' comes with us when you consider our bodies are more than a self contained ecosystem. And consider the relativity .... a few thousand years ago there might have been 1million people alive with no Asthma ,but now theyre might be 2million alive and half have asthma... have things gotten worse/stayed the same/or gotten better for the population as a whole!