When considering the statistics on bacteria, CSU Immunology and English professor Gerald Callahan says people ought to think again about germs.
For example, there are 10 times more bacterial cells than human cells in a human body. Bacteria outnumber humans by more than 10 quintillion, Callahan said.
He came across these figures four or five years ago. The chain of thought they started culminated in a book, Infection: The Uninvited Universe, published late last year by St. Martin’s Press.
“I began to think, ‘Wow, if it’s really a 10:1 ratio, if by number I’m really just 10 percent human, this relationship can’t be the one that we’ve been told about for so long,'” Callahan said. “It can’t be an us-against-them situation or I would have lost the battle a long time ago.”
The relationship is much more complex. Though some infectious diseases kill, people need bacteria. And germ phobia may be hurting people much more than they realize, Callahan said.
Children especially need to be exposed to bacteria. Without early infections, people and other mammals don’t develop normal immune, digestive or nervous systems.
In the name of protecting children, parents may actually be hurting them by over-sterilizing their homes.
Callahan cites an early study leading to this conclusion, conducted when the Berlin Wall came down in 1989. Public health officials expected that poverty and terrible air pollution in East Germany would have created a huge backlog of asthma patients from East Germany seeking treatment in the West.
They were wrong, according to the study. Asthma rates were much lower in East Germany than in the West, where people received better health care and more immunizations and antibiotics. Scientists now believe that children develop asthma more frequently when they are raised in comparatively sterile environments.
“The more education you have, the more likely it is your child will have allergies or asthma,” Callahan said.
This, Callahan said, is probably because educated parents tend to have more money and be aware of bacteria’s power to sicken, so they overprotect their children.
“Although we know our children may meet some bad people, it would never occur to us to say that we’re not going to let our children meet any people,” Callahan said. “Yet that’s what we try to do with bacteria and it doesn’t work.”
Callahan’s book also addresses the dark side of bacteria, giving readers a glimpse of their deadly potential. This section also examines bacteria’s ability to resist antibiotics.
Citing research, Callahan points out that some strains of Staph bacteria that have shown resistance to the once powerful antibiotic Methicillin can be traced to intravenous drug users who routinely combined their drugs with antibiotics before shooting up. A drug user usually does so in an attempt to avoid infections from dirty needles.
Methicillin-resistant Staph led to 94,360 major infections, and was associated with 18,650 deaths related to hospital stays in the United States in 2005.
Callahan hasn’t always spent his time thinking about the role of bacteria in human life. When he began as a professor of immunology at CSU, he studied cancer and the immune system. He spent most of his time on research and had his own laboratory, a life-long dream. But he wrote poetry now and then on the side.
His wife signed him up for a continuing education poetry class 12 or 13 years ago, which led Callahan to pursue his writing more seriously.
“At that point I wasn’t teaching very much, my research wasn’t going well, so I was able to sneak away a lot on 4 day weekends and such,” Callahan said.
These trips, often to the Colorado River, became essays that eventually came together in Callahan’s 1998 book River Odyssey.
Along the way, Callahan quit working in the lab and picked up a joint appointment with the English department.
“I love to write,” Callahan said. “Every time I walk by my computer practically, I get sucked in.”
Callahan’s next project will explore misperceptions about human sex, and he plans to address is the scientific basis for a continuum of sex.
“The process of sexual development is so complex. It isn’t like flipping a switch and you get a boy or a girl, it’s more like a volume control,” Callahan said.
Staff writer Beth Malmskog can be reached firstname.lastname@example.org.