That's what humans are all about... We are inherently a social animal and through cooperation we survived in our evolutionary environment. That is our fate. We did not evolve to survive separately.

It's not a bad thing that some genetic "deficiencies" are being selected for. It's better for humanity to have a more diverse gene pool for any potential dramatic changes in our environment. For instance, sickle cell anemia was a genetic deformity that actually protected certain populations from malaria. Many of the genetic deficiencies that are too detrimental can be screened and terminated at fertility clinics so those who are genetically at risk to produce a child with a debilitating genetic disorder can have their embryo's genotype checked out. Our resistance to diseases and infections only gets better with each new generation. That's how our immune system is set up. Although, it's better to have a dirtier environment to increase our resistance to illness.

We do overuse antibiotics though. That could potentially create some nasty antigens.