High testosterone levels may be key in the transmission of infection, it has been suggested.
Biologists who conducted a study on mice said the results could help to explain why males were "more likely" to get infected and spread disease in a population, Eurekalert reports.
In news that may be of interest to people researching the immune system, Daniel Grear, a Penn State doctoral student in ecology, Sarah E Perkins, a postdoctoral fellow and Peter J Hudson, the Verne M Willaman chair in biology and director of the Huck Institutes of Life Sciences at Penn State, examined the effects of the hormone in mice.
"We know that testosterone makes males more susceptible to disease," said Mr Grear, adding: "We wanted to find out if it impacts their behavior as well and how that increases their ability to transmit disease."
A total of 24 male mice were randomly treated with testosterone implants while 25 received placebo implants and some received none.
Those with high testosterone levels were found to impact the behaviour of those around them.
In related news, researchers at the US National Institutes of Health found that injecting mice with cancer with high levels of vitamin C reduced their tumors.
