State to close half its mass vaccination sites, focus on doctors' offices

Massachusetts will transition its focus from large vaccination sites to small physician offices with the closure of four of those sites over the next two months. The state's vaccine command center is in discussions with the Massachusetts Medical Society to increase physician access to vaccines, with additional primary care providers set to receive supplies by the middle of May.  More appointments will also become available at 22 regional collaboratives, pharmacies, mobile units and walk-up clinics.  Four…