Too clean for our own good

I'm not imagining it. It is confirmed that children have more allergies today than before. And now there is a theory: we are too clean for our own good. Newsweek, Nov.5, 2007: "The immune system is designed to battle dangerous foreign invaders like parasites and viruses and infections. But clean water, antibiotics, and vaccines have eliminated some of our most toxic challenges."

It is hypothesized that we have so laudably eliminated exposure to physiological harm that we are not strong enough to fight off the meekest microbial invaders: "Without hard-core adversaries…the immune system starts battling the innocuous --- egg or wheat --- instead….Children who grow up on farms, where they are in constant contact with dirt and animals, are less likely to develop allergies."

I am wondering if it's not the same on the spiritual plane. Are we forever wishing and praying away the very suffering and "hard-core adversaries" in our lives that the Lord has meant for our spiritual strengthening? Might we not be better off (and on better biblical grounds) praying for endurance in trials rather than always the removal of them?

For allergies, many scientists now recommend "controlled exposure" to harmful stimuli. Isn't that exactly what God does?