MONROVIA, Liberia — Nurses on an Ebola ward in Liberia must cut up old overalls to serve as makeshift head-coverings to protect themselves from infection, despite international promises of more equipment, a health worker said Thursday.

The Ebola outbreak in West Africa has killed 1,900 people, and officials warn that time is running out to control it. Nigeria, where previously the outbreak had seemed relatively contained, is racing Thursday to track down people who may have been exposed to the disease in recent weeks.

A severe lack of protective gear for health workers, who are at high risk of infection because of their close contact with the sick, is a major obstacle to stopping the outbreak.

Health workers account for about 10 percent of the deaths so far. Much of the gear must be destroyed after use, so wards need a constant flow of equipment.

One nurse at a hospital in Monrovia, Liberia’s capital, said she and her colleagues have resorted to cutting up their old uniforms and tying them on their heads. They cut holes in the fabric, so they can see, said the nurse, who spoke on condition of anonymity because she was not authorized to talk to the media.

“It is really pathetic,” she said. “We are not equipped to face the situation.”

With no googles to protect them, their eyes burn from the fumes of chlorine used to disinfect the ward, the nurse said.

David and Nancy Writebol, American missionaries who worked at another hospital in Liberia, echoed those concerns, speaking to The Associated Press in North Carolina.