Is more advanced medicine actually reducing our body's immunity over generations?

Question

Never before in the history of the Earth have we had so many antidotes, vaccines, and cures for so many diseases. Is this actually altering the body's genetic structure over time so that over a period of a few generations, the human immune system is actually less resistant to diseases? In evolution, when something is not needed, it is eventually phased out. Animals that move underground ultimately lose their eyes because they no longer use them. Since we are providing man-made immunity to diseases, does the body recognize this and reduce its own defenses since they are not required to be used as much?

Is using antibacterial and sterile products at home having the same effect on us genetically?

And on a side note, does this increase the capacity of diseases to become more resistant to our immune responses?

Answer 1

Ok you have to get two things differentiated.

The immune response to a pathogen has nothing to do with our genetics other than the actual production of immune system cells.

Our body fights invading substances mainly by two mechanisms.

1) Immune system cells activley search and destroy the pathogen ( and foreign substances).

2) Our cells can produce special substances which actively destroy or remove the pathogen or foreign substance.

As infants through to adulthood and throughout life our body is exposed to many potentially toxic and pathogenic substances, but our immune system is able to deal with these invading substances and produce a "shortcut" (memory)response if we ever encounter that substance again.

If we never in our lives come across a specific substance Eg. The avian flu our immune system has nothing similar to compare it to, and hence we are at risk of becoming ill. A good example is the WHO initiated scheme to eradicate smallpox (a virus). They were sucessful. The only issue is that since the virus no longer is endemic nor occurring in the world(that we know of) people have stopped vaccinating against it.

If for some reason the virus ever came back, there would be a world wide pandemic since no-one has any natural or memory immunity hence many many people would die.

I hope this told you that vaccinating and our immune response is not related to our genetics. Just because the world would have less diseases doesn't mean our immune system will become redundant. Every breath you breathe, sip you drink, piece of food you eat is covered in bacteria all which (if you had no immune system) would cause disease.

NOTE: The immune system is complex i tried my best to simplify it for you as well as i could.

Answer 2

Vaccines actually activate / stimulate our immune systems. However, using antibacterials forces the bacteria to adapt their defences and become resistant, which makes it harder to kill them.

That's why we need to be exposed to certain things (and vaccination is a controlled way to do this) rather than making those things stronger before our immune systems have a chance to develop it's own resistance.

So, basically...our immune system and bacteria are both capable of adapting. But, yes...there are some nasty diseases out there so unless we somehow destroy all the pathogens we will always need our immune systems.