CHAPEL HILL, N.C. College football players sick with food poisoning transmitted the virus to the opposing team on the field in the first documented case of its kind in sports, researchers say.
The Duke players vomited in the locker room and on the sidelines during the Sept. 19, 1998, game against Florida State, which they lost 62-13.
The virus then spread to the other team.
"The only contact between the two teams was on the playing field," said Dr. Christine Moe, an assistant professor of epidemiology at the University of North Carolina at Chapel Hill.
"The virus was passed by people touching each other's contaminated hands, uniforms and maybe even the football itself."
Game films showed ill Duke players with vomit on their jerseys colliding with opponents, and Duke players wiping their mouthpieces on their hands, then touching opponents' faces and later shaking their hands.
In a study in Thursday's New England Journal of Medicine, the researchers urged coaches to bench players with such illnesses and stress the importance of handwashing when ill and after using the bathroom.
The food- and waterborne virus, which is from a family called Norwalk-like viruses because the first outbreak was detected at a Norwalk, Ohio, school in the late 1960s, causes vomiting, stomach cramps and diarrhea.
The virus family causes an estimated 96 percent of cases of nonbacterial gastroenteritis, or inflammation of the stomach and intestines.
It gets far less attention than food-borne bacteria such as E. coli because it causes no permanent damage and rarely kills anybody.
Person-to-person transmission sometimes occurs in crowded living situations, such as on cruise ships.
But this is the first documented case of transmission among participants in a sports event, according to Karen Becker, an epidemiologist at the Centers for Disease Control and Prevention who led the study.
Many Duke players and staff fell ill by game time, a day after they ate contaminated turkey sandwiches in a box lunch, Becker said.
"By the middle of the second quarter, several players, including three of the defensive starters, were on IVs in the locker room," Becker said.
Altogether, 43 of the Duke players and staff who ate the turkey, or 62 percent, got sick. They transmitted it to 11 other Duke personnel who had not eaten the sandwiches and to 11 Florida State players but no staffers.
"It emphasizes the infectious nature of the organism," Becker said.
The virus is hardy enough to survive on unbleached surfaces and carpet for months, Dr. Mary K. Estes, a professor of molecular virology and microbiology at Baylor College of Medicine. She is developing a vaccine and hopes to have it ready in five years.
DNA testing allowed the researchers to determine that players on the two teams had the same rare virus strain, proving the Florida State athletes could only have been infected on the field. The researchers also traced the virus to a particular food preparer.