Health officials say they're seeing more cases of pertussis, or whooping cough, around the country and in Monroe County and surrounding areas.
In neighboring Ontario County, a case was reported this week at Victor High School.
Dr. Michael Pichichero with the Rochester General Hospital Research Institute says it appears the latest vaccine, which replaced a previous shot that caused several reactions including a high fever, isn't lasting as long.
So an extra booster shot may be needed at age 11 or 12 and every five years through their teenage years, according to Pichichero.
Another problem, he says, is that many parents are claiming religious or personal exemption, and that leads to a larger number of unvaccinated children in middle and high school.
He says the Centers for Disease Control is expected to decide this month whether to endorse the five-year pertussis booster.
The CDC says whooping cough is highly contagious, and is known for its uncontrollable, violent coughing, which can go on for ten weeks or more.