The teenager, living in a remote shepherds' community in south Siberia's Tuva Republic, was hospitalized on Tuesday after catching the rodent and bringing it home in his hat. His grandfather immediately killed the animal, and called a doctor.
"The tests for plague taken from the boy are negative. The boy is feeling well and there are no symptoms of the disease," a spokesperson for Rospotrebnadzor said.
The boy will be discharged after the six-day incubation period, he said.
No other residents of the area, which has been thoroughly disinfected, have applied for medical help, the spokesperson said. Medics from the regional plague prevention center are carrying out anti-epidemic measures in the area.
Plague, caused by the yersinia pestis bacterium, can be transmitted from rodents to humans via fleas. Bubonic plague is now extremely rare in industrialized countries, and can be treated with antibiotics.