HELENA - The Jefferson County Health Department says a student at Jefferson High School in Boulder has tested positive for whooping cough.
Superintendent Jim Whealon says recommended to eight families that their children be tested due to their level of contact with the ill student.
Whealon said on Friday that he's had a lingering cough, so he also was tested.
Whooping cough, or pertussis, is a bacterial infection that causes uncontrollable, violent coughing. County Health Officer Joan VanDuynhoven says it's most contagious in its early stages.
Students are usually vaccinated before seventh grade, but the vaccine isn't 100 percent effective and some students don't receive the shot.
Bozeman had about 40 cases of whooping cough last fall. There were several cases in Park County and one in Lewis and Clark County.