N95 and surgical masks, the backbone of protection against viruses in medical facilities, were still in short supply in many nursing homes at the end of the summer, according to a new analysis of federal data.

A report released Tuesday by the nonprofit U.S. PIRG Education Fund found that a fifth of nursing homes in late August had less than a week’s supply of some type of critical personal protective equipment (PPE). That is considered a dangerously low supply. The new report used data submitted by nursing homes to the U.S. Centers for Medicare & Medicaid Services.

Nursing home residents have been especially hard hit by the pandemic. They account for less than 1% of the population but more than a quarter of deaths, the report said. The virus has caused more severe disease and death in the elderly and people with multiple health problems.

The report found that shortages of N95 and surgical masks, gowns, eye protection, gloves, and hand sanitizer worsened over the summer. N95 masks do the best job of filtering out viruses. They were the hardest protective gear to procure, with close to 8% of nursing homes unable to get any in August and 17% with less than a week’s supply. Hand sanitizer and gloves were the easiest.

New Mexico, West Virginia, and New England states reported having a particularly hard time getting masks.

Seventeen percent of Pennsylvania nursing homes said they had less than a week’s worth of N95s and 13% said their supply of surgical masks was low. That compares with 20% in New Jersey for N95s and 8.9% for surgical masks.

In Pennsylvania, 9% of nursing homes said they had no N95s and 8% had no surgical masks. New Jersey reported no N95s at 15% of facilities and no surgical masks at 8.6%.

U.S. PIRG said several steps could improve supply, including making “full use” of the Defense Production Act to increase U.S. production of PPE, national coordination of supplies, and more financial help for nursing homes.