New London — Yale New Haven Health will begin vaccinating people 75 and older Wednesday, including at sites in New London and Old Saybrook.

Those 75 and older — the first group in the state’s Phase 1b — can make appointments on a first-come, first-served basis by visiting ynhhs.org/covidvaccine. The New London site is the L+M Multispecialty Center, 194 Howard St., while the Old Saybrook site is the Old Saybrook Medical Center, 633 Middlesex Turnpike. Sites in North Haven and Trumbull also will open next week, and a Greenwich site will open the week of Jan. 25.

Yale New Haven Health will add more sites as they are approved. Vaccinations only will be given to those who have an appointment.