First  Prev  1  2  Next  Last
Post Reply Lack of STD Immunity
2841 cr points
Send Message: Send PM GB Post
M / Houston, Tx
Offline
Posted 5/21/15
The biggest question I had for my Professor was
"If STDs were so common why aren't we immune to it yet?"

What he replied was "The same way we aren't all immune to the Cold Flu, STDs aren't specifically destroying the entire human race- they are just lingering around, until they threaten Humanity- we will not be built to survive from something like that."




Why do you suppose we aren't immune to something like this yet?
Posted 5/21/15
ate te te te te te...listen to your teacher >:[
11734 cr points
Send Message: Send PM GB Post
F / America
Offline
Posted 5/21/15
In terms of how a disease/ virus spreads, it needs a large amount of people who would be vulnerable to it. I guess that our bodies just aren't advanced enough to combat against viruses yet, especially STDs.
2524 cr points
Send Message: Send PM GB Post
18 / M / Out of sight (But...
Offline
Posted 5/21/15 , edited 5/21/15
I guess it's our bodies' way of saying, "Eh, I'm sure we'll be fine."
11670 cr points
Send Message: Send PM GB Post
21 / M
Offline
Posted 5/21/15
There are so many types of viruses that causes colds that our immune system doesn't help much 'cuz you probably won't come across the same cold-inducing virus again. If I remember correctly, STDs tend to change forms so that our immune system doesn't recognize them in order to fight back.

I suppose it takes extreme measures to force evolution against them as they're not that big a deal ATM.
30958 cr points
Send Message: Send PM GB Post
M
Offline
Posted 5/21/15 , edited 5/24/15
It's not outrageous, but the answer was grossly simplified. Also, your question was grossly overbroad so it would be hard to answer for anyone.

I'm not a doctor but broadly there are three things that count as STDs: Bacteria, Viruses, and parasites.

Bacteria are small organisms that can colonize parts of you and cause problems. Most times the immune system will fight them to the death, but "winning" simply means that group of bacteria is wiped out or reduced to such a tiny population to no longer matter. (Note we have tons of "good" bacteria living in us, not all are a problem.) If your immune system calms back down, or if it becomes weakened, the same sort of bacteria might "invade" again. Gonorrhea for instance is a bacterial STD. There is a good treatment based on penicillin but since there are just so many people that keep having unsafe sex (and go untreated) it continues to thrive in the "wild."

If your house gets mice because you leave garbage all over, and you kill those mice, it doesn't mean you are immune from mice in the future. When you start throwing the garbage all over again, more mice might come.

Parasites like crabs are also considered STDs. Very similar to bacteria, except these are actual little "bugs," they are more complex than bacteria. They have legs, heads, etc. or are like small worms. These are little creatures that make their home on or in you. Fleas are parasites, but they get around by jumping and such. Crabs don't jump far, but they can jump enough to go person to person in close contact.

Again, these can generally be removed, but it doesn't make you immune from future exposure.


Viruses are different. They are like a foreign kind of life, not really fitting our classical definitions of being a living organism. Pretty much they only exist to reproduce, though some can be beneficial at times. Many viruses constantly evolve in the wild. Constantly. Some just don't evolve much at all. Virology is a field that always needs more research.

Generally you can become immune to a virus if it doesn't kill you -- the catch is that the way the immune system works, you will only build an immunity against a virus after exposure to it. Your body will fight with it a while, but eventually figure out the trick, and that particular virus loses its power to survive inside you. The immunity can extend to extremely similar viruses. Immunity can last for a long time, but is not necessarily permanent.

It's not so simple though because so many viruses don't stop evolving. Your body can figure out the trick to beat Virus A, but out in the wild some of the Virus A (for some reason) mutates over time into Virus B. Now in the wild there is both a Virus A, and now a new Virus B. If you come into contact with Virus A a second time -- you don't really notice. Your body already knows how to beat Virus A, it doesn't matter. The problem is Virus B. If you get Virus B, your immune system pretty much has to start over from scratch to figure it out. Our bodies aren't nearly as smart as our brains can be, the immune system isn't "proactive" about developing countermeasures -- so they are caught by surprise constantly. It's an arms race where the body is always a little behind.

Of those viruses that simply don't evolve much at all, vaccines can be produced. There are different ways of making a vaccine -- some use a little bit of a given virus injected, or a partially-destroyed virus (it looks similar enough to the real thing but is too weak to really attack you) -- such a small amount it's almost impossible for you to "get sick" before your body figures out how to beat it. It's like an invading army of 1, where if you were exposed in the wild your body might be facing an invading army of 1000 or more little germs at once. Since the immune system learns to beat what it fought with, even if you do get invaded in the future by that same kind, your body already learned the trick.

Unchanging viruses can be controlled and eliminated, even if they are spread sexually. Obviously those aren't the ones that we care much about these days. You would get sick once, and then be cured of that particular virus so nobody talks about those. It would be hard to even encounter them because your "partner" would also have fought it off and it wouldn't be alive when you interact with them.


The problem is viruses the body can't figure out how to beat. It's an arms race, and some viruses are winning. They are winning against body and brain -- we haven't developed cures for them yet. There are different ways a virus can survive and pop up from time to time. Some will seem to be dead, but they hide inside bone marrow where your immune cells can't actually reach them. After a while, they spring back to life -- hey I'm still in here! Your body will fight them off again, but they retreat back to the bones (or other tissue that is hard to reach). HIV/AIDS essentially is invisible to the immune system so we haven't figured out a way to make a vaccine relying on the immune system. And viruses don't stop evolving once they are inside you. If they find a hiding spot, they will keep becoming slightly different and cause problems continuously.





Oh, about the "not strong enough to threaten humanity" part -- your teacher was going into evolution theory with that.

He means that for humanity as a whole to become immune to a disease -- instead of each person gaining immunity on a case by case basis -- there would have to be some nearly cataclysmic outbreak that kills almost everybody. Almost everybody. The people that got it and survive are different somehow -- maybe they had different genes or something, but the superbug can't kill them. They're the only people left now in humanity.

So future humanity, from those survivors, would be generally immune from that particular killer disease. Assuming anyone survived of course.


Since the STDs we have aren't quite at the level of wiping out people -- a person will get infected, but not die, at least not very fast -- the disease can continue to spread person to person. We're back to the model of "case by case basis." A person can have the disease, pass it along, and keep living. It's an annoyance to deal with the symptoms, but the disease is too strong to be beaten by the immune system or existing drugs, yet too weak to actually kill people outright. So STDs piddle along. They aren't enough of a problem to cause extinction, but are enough to be annoying.

Also because they don't cause extinction, humans don't pay all that much attention to them. Consider the funding that can go to eradicate diseases when people really *try* to do something. There just aren't very serious efforts from world governments to end particular STDs, they have other stuff they feel is more important to spend their time on.

The world puts a lot more attention into bird flu and Ebola than most STDs will ever get.

9551 cr points
Send Message: Send PM GB Post
18 / M
Offline
Posted 5/21/15
Well you see we have this great thing in the modern era called condoms. There not perfect but they help.
349 cr points
Send Message: Send PM GB Post
M / in a Parallel wor...
Offline
Posted 5/21/15 , edited 5/21/15

megahobbit wrote:

Well you see we have this great thing in the modern era called condoms. There not perfect but they help.


don't think everyone is satisfied with them, because they say it doesn't feel the same.
Wonder if they still say that during the baby shower
9551 cr points
Send Message: Send PM GB Post
18 / M
Offline
Posted 5/21/15

DJTACO wrote:


megahobbit wrote:

Well you see we have this great thing in the modern era called condoms. There not perfect but they help.


don't think everyone is satisfied with them, because they say it doesn't feel the same.
Wonder if they still say that during the baby shower


Kek
11660 cr points
Send Message: Send PM GB Post
19 / M / Cali
Offline
Posted 5/21/15

DJTACO wrote:


megahobbit wrote:

Well you see we have this great thing in the modern era called condoms. There not perfect but they help.


don't think everyone is satisfied with them, because they say it doesn't feel the same.
Wonder if they still say that during the baby shower


Contraceptives yo
349 cr points
Send Message: Send PM GB Post
M / in a Parallel wor...
Offline
Posted 5/21/15 , edited 5/21/15

Contraceptives yo
Still, the unlucky one bites the dust.
unless of course, they made it completely impossible.
Posted 5/21/15 , edited 5/21/15
they're too strong
wear condoms kids
27230 cr points
Send Message: Send PM GB Post
27 / M
Offline
Posted 5/21/15 , edited 5/21/15
Because humans aren't evolved yet to be adequately resistant to some diseases and germs mutate and evolve, too. And those infected either haven't been vaccinated against these particular diseases before or there is no vaccine because the bug is a virus.

Humans are evolving, viruses and bacteria are evolving, an inadequately defended body encounters a bug that makes it through the defenses. The invading bacteria or virus finds the conditions in the human body good for setting up base. Symptoms are usually caused by the body trying to fight off the invaders. You could carry a disease and not know it as well, if it is dormant or your body isn't responding for some reason.
Posted 5/21/15 , edited 5/21/15
The answer is simple... I learned this in Microbial Genetics. But I only learned the reason for HIV, not other STI (the proper terminology used nowadays, as infections don't always show disease).


Viruses don't have a proof-reading system (think of it like spell check on Microsoft Word) in their DNA or RNA (1 stranded DNA). This allows them to mutate at exceedingly fast rate, the human immune system cannot catch up with that. So every time our memory cell remembers a protein, the virus suddenly mutates into another shape so that the memory cells become ineffective. It's the same reason we can't be immuned to Influenza virus.

Humans and other eukaryotes have a proof-reading system built into our DNA, so that our DNA don't mutate as often, (it does mutate, but at a slower rate, incredibly slow). And mutation often lead to mortality in humans and complex organisms.

____

Hope that helps. This is why I say... I think virus >>> humans.
49109 cr points
Send Message: Send PM GB Post
Offline
Posted 5/22/15
Simply stated STD's aren't static.
First  Prev  1  2  Next  Last
You must be logged in to post.