OGDEN -- How many organisms are living on your body?
Most of the genes living on you are viral, fungal and microbial -- and your body has more of those on it than human genes, says an evolutionary ecologist.
Rob Dunn, a biologist and writer in the Department of Biology at North Carolina State University, was the keynote speaker Thursday during the 68th annual Ogden Surgical Medical Society Conference at the Eccles Conference Center.
Dunn is the author of the 2011 book "The Wild Life of Our Bodies: Predators, Parasites, and Partners That Shape Who We Are Today."
In the past, Dunn said, scientists have paid little attention to the ecology and evolution of the species that not only live around us but actually live on us.
We have coexisted with organisms since the beginning of time, he said. They have helped shape our biology and affected our health.
We have spent so much time scrubbing nature off our bodies that we've also made ourselves sick, Dunn said.
While clean living is beneficial in some ways, we should allow ourselves to continue to share the world with these organisms without so much fear, he said.
For instance, he said, Crohn's disease, a chronic inflammatory disease of the gastrointestinal tract, seems to be kept at bay from certain internal parasites.
Pregnant mothers who owned a dog during pregnancy have been shown to have children with reduced autoimmune disorders and allergies, which may be related to some pathogen on the animal.
And if you think your appendix is worthless, think again. Dunn said people who still have their appendix recover more quickly from severe gut infections such as C. diff, which causes severe diarrhea, than those who don't. That's because the appendix may serve as a reserve for beneficial bacteria.
"We have also tested homes to see how many species are living among us," he said. "In my home, we found 120, which is about the same for everyone's homes."
Some of these species live on your crumbs, in dark corners, in your bed, in your water heater, on your shower heads and just about everywhere else, Dunn said.
For instance, the crumbs that fall on the floor from breakfast will, if left long enough, eventually be gathered by ants, roaches or crickets. In addition, hundreds of bacteria species eat at your dead skin, which you shed during sleep. If you let these things be, Dunn said, they will go through their own cycle of taking care of business.
The three-day medical conference also included topics on pediatric issues such as anxiety and depression, fevers, rashes and chronic abdominal pain. Also discussed were neurological illnesses, gastrointestinal diseases and obstetrics and gynecology.
Other keynote speakers included Dr. Edward James O'Neil Jr., who spoke about global health inequality, and Dr. David A. Ansell, who spoke about primary care medicine on Chicago's west side.
The Ogden Surgical Medical Society was founded in 1946.