Immunity

I have had a long love for the life sciences. I actually had a college counselor say, “Chef! Stop taking biology courses! You’re not a biology major and you’re just hurting yourself.” And she was right, too. But she didn’t call me Chef.

This whole bird flu thing, although not an above-the-fold headline any more, still has me thinking. And not of my own life as much as marveling at the way the human organism responds to such threats.

There was a time when immunity was a matter of how strong your immune system was. If you contracted a disease, you lived or died, end of story. Immunity was based on the individual organism’s ability to fight off disease once it got inside.

But that’s changed, at least for homo sapiens. Starting a few millennia ago and escalating in the past hundred, humans have started fighting disease at the population level as well as inside our individual bodies. We started with simple steps, like rudimentary quarantines, and have come so far that we have global systems to identify diseases, disease pathogens and vectors, and ways to control them.

This is something that most people living today take for granted, but consider the ramifications for a population of living things when such things become possible. Think about how dramatic it would be if frogs, gazelle, or goose did that.

We have representatives of our species monitoring the overall health of the rest of the planet’s population. They’re watching for illnesses, and issuing warnings when a handful of our fellow creatures in a small, crowded corner fall victim. And as a species, we respond. We shift our resources, plan for outbreaks, and take preventative measures. We even change our environment to limit disease vectors.

I’m sure there are some animal populations other than humans that do this to some limited degree. Birds that discard a sickly chick, predators that instinctively destroy a sick member of their pack.

But we're doing something entirely different. Here we are, an awkward primate species with a large brain, proactively looking for disease, developing means of prevention and even cure. We still rely on the individual organism’s immune system, but it’s almost like a last resort. We’ve developed a new, primary immune system, one that protects us as a species, and not just as individual critters crawling around spawning and eating.

In terms of evolution, I think that’s revolutionary. It’s like the appearance of the first rudimentary feathers, or even a blood-rich lining that permits an occasional gasp of air for breath. I only wonder if it can persist. But I guess none of us is permanent.