Nursing homes, small physician offices and rural clinics are being left behind in the rush for N95 masks and other protective gear, exposing some of the country’s most vulnerable populations and their caregivers to COVID-19 while larger, wealthier health care facilities build equipment stockpiles. … While supply chains have adjusted, and the availability of PPE has improved dramatically since the mayhem of the spring, limited factories and quantities of raw materials still constrain supply amid the ongoing high demand.