The other day I was chatting with a woman online and she mentioned Stephen King’s masterpiece, “The Stand” (that the cover photo to the right). In that book, a mysterious disease appears and kills off 90% of the population within a few weeks. The remaining 10% are immune and survive and then begin to rebuild society.
She notes that King must have really done his research since every recent century has ended with some kind of plague that killed off many people when the doctors couldn’t cure it in time. The most memorable examples are typhoid fever and bubonic plague.
She figures that HIV/AIDS is the most recent end-of-the-century plague. To some degree, she’s right, since there is no cure for HIV/AIDS. But, there are many key differences between previous plagues and HIV.
First, this is the first end-of-century where doctors actually had decent medical knowledge that went beyond using leeches and sacrificing goats. Doctors can actually look at a disease under a microscope and devise a plan to kill it. Granted, they haven’t yet figured out a way to kill HIV, but they pretty much know what they are dealing with and have made good progress in slowing down the rate at which it kills its victims.
The second difference is that HIV/AIDS is transmitted far differently than classic plagues. Previous plagues spread simply by breathing in air contaminated with the disease or via sweaty hands. It spreads like wildfire in areas where cleanliness is minimal. If you are around infected people, and it is difficult to clean yourself, you can’t take any reasonable precautions to prevent yourself from becoming infected also.
HIV/AIDS, however, spreads one person at a time and spreads via invasive contact with infected body fluids from another person, usually blood or semen. Preventing infection is trivially easy — just be careful not to let other people’s body fluids get into your bloodstream. Wearing condoms when having sex and using rubber gloves when handling blood will prevent the vast majority of almost all infections. Unfortunately, many people still get careless and become infected.
I pointed out that HIV/AIDS does not quite live up to the classic definition of a plague. It does not kill quickly nor spread quickly. With new drugs, HIV/AIDS patients can live 25 or more years after infection. I have a friend who has lived with the disease for 32 years now and he’s still quite healthy. So, I tell the woman that I am chatting with that traditional cancer is a much bigger plague and that the average life expectancy of new cancer patients is far less than that for new HIV/AIDS patients.
She goes on to note that these centennial plagues are just a form of natural selection. I disagree and say that the term “natural selection” is primarily applied to situations where an animal’s body has a mutation or new physical advantage that gives it a better chance of surviving and procreating than animals that don’t have that difference. Taller animals can reach fruit higher on the tree than other animals, for example.
The survivors of real-life plagues generally have no physical differences in their bodies that allowed them to live while others didn’t. Plague victims usually just happen to be at the wrong place at the wrong time to contract the fatal microbe. It’s just a matter of bad luck (Note that I am ignoring the possibility that a few people might actually have a natural immunity to a particular plague. That would, indeed, be natural selection coming into play. But, it hasn’t been the case so far that plague survivors with immunity reproduce and create a community of children with immunity).
When a person survives a flood and then goes on to reproduce, it is not called “natural selection.” That’s just bad luck for the victims and good luck for the survivors. Flood survivors won’t breed children with any special abilities to survive another flood. The same goes for catching a plague and dying.
So, what do you think? Is HIV/AIDS the plague of the century? And, do you think that natural selection plays itself out through plagues?