The Health Department will offer free flu shots for Mansfield residents and employees, 19 years old and older, during a clinic from 4 to 6:30 p.m. this Thursday at Town Hall. Health Agent Scott Leite said 200 doses of adult vaccine are available, and sign-up is not required. This is the second clinic the town has offered this year. Last month, 300 doses, in mist and shots, were administered during a family flu clinic. “We were able to do all ages, but this time we only have the adult vaccine,” Leite said.