FRIDAY, Aug. 15 (HealthDay News) -- In mice, high levels of the male sex hormone testosterone may play an important role in the spread of disease, according to Penn State researchers.

Previous studies have linked testosterone to immune system suppression and found that males experience more bouts of disease and are responsible for more disease transmission than females. But it's not clear why males are more likely to spread disease.

"We know that testosterone makes males more susceptible to disease. We wanted to find out if it impacts their behavior as well and how that increases their ability to transmit disease," Daniel Grear, a doctoral student in ecology, said in a university news release. "Our plan was to raise the testosterone levels in wild mice and measure the disease risk they posed to the population."

Wild mice at different sites were trapped and received either testosterone implants, sham implants, or no implants. All the sites were trapped twice a week for six weeks before and after treatment. Recapture data showed that contact among all mice significantly increased when testosterone-treated mice were present.

"These findings suggest that even if some individuals in a population have high levels of testosterone, they can impact the behavior of those around, and drive the transmission of diseases transmitted by close contact such as the respiratory pathogen bordetella, Grear said.

The study was presented Aug. 8 at the annual meeting of the Ecological Society of America.

More information

The MedlinePlus Medical Encyclopedia has more about testosterone.