Methicillin-resistant Staphylococcus aureus (MRSA) superbugs are more likely to affect players of contact sports than other athletes, according to a new study. The close contact of athletes in this class of sports appears to spread the drug-resistant bacteria from one person to another.

Infections of MRSA usually occur under skin and in soft tissues. They can be treated, and usually heal, however invasive MRSA infections can be more serious. They are responsible for roughly 18,000 annual deaths in the United States.

The bacteria can enter bodies through open wounds, which are more common in players of contact sports than among other athletes. Those infected with the disease can then spread MRSA to others, either on the field, or by sharing towels in the locker room. A few years ago, the superbug was most often contracted in hospitals. Now, infections are far more common in the general populace, especially among athletes.   

Researchers tracked 377 male and female student athletes over a two-year period. Of these subjects, 224 played contact sport, while the others took part in golf, cross-country running, and similar activities. Nasal and oral swabs were taken from the students once a month. Investigators found that 23 percent of those who played non-contact sports were exposed to the bacteria, while the disease-causing organism was found in 30 percent of those who took part in contact sports.

Contact sport participants were not only more likely to contract the bacteria, but were also infected by the organisms for a longer period of time than those who took part in gentler activities.

"This study shows that even outside of a full scale outbreak, when athletes are healthy and there are no infections, there are still a substantial number of them who are colonized with these potentially harmful bacteria," Natalia Jimenez-Truque of Vanderbilt University Medical Center said.

Between five and ten percent of Americans have been infected by MRSA at some point in their lives. If it becomes invasive, the bacteria can lead to pneumonia, along with infecting the blood, heart, and lungs. Doctors are then often forced to treat the disease with powerful antibiotics, delivered intravenously.

Researchers found that locker rooms and equipment used by athletes in the study were generally free of the bacteria, suggesting most transmission was either person-to-person or spread through shared towels and clothes.

"Sports teams can decrease the spread of MRSA by encouraging good hygiene in their athletes, including frequent hand washing and avoiding sharing towels and personal items such as soap and razors," Jimenez-Truque said.