It's not natural

[Torrere]

I would see "natural" as being the circumstances that we were made (evolved, created) to live in and the things that we were made (evolved, created) to do.

The way that we live is tremendously different from the way that we lived even eight thousand years ago. There are probably twenty or thirty people living in the same appartement building that I do (I'm not sure if the bottom level is actually a floor of appartements). During most of human (pre)history, this number of people would have lived in a much, much larger space.

A hundred years ago, there were no monitors. I've been on the computer for three hours (agh!). This would have never happened even a hundred years ago. Hell, most humans have spent the majority of their time looking for food. Through most of my life, the majority of my time has probably been spent reading. Is that natural?
Nah.

Traditionally, people spent the majority of their time living in small groups. Most of the human diseases act slowly, spread slowly, and leave the victim a long time to live (malaria). The majority of the diseases we worry about today (eg, influenza) spread quickly and act quickly -- they aren't native to humanity, they're native to herd animals whose ways and lifestyles and vulnerabilities we're adopting (fowl, pigs, cows, chickens). We have resistance to natively-human diseases (sickle cells), much more so than to the diseases we didn't grow up with.

As I've heard it, Whit, HIV/AIDS is derived from primates. I've read that AIDS may have been recorded in human populations 80 years ago that were in close contact with chimpanzees. Some primates can contract the Simian Immunodeficiency Virus.