Bacteria beneath the long fingernails of nurses have been linked to the deaths of babies in an intensive care unit in a hospital in Oklahoma City, federal and Oklahoma health officials said yesterday.

Epidemiologists who investigated the outbreak of bacterial infection at Children's Hospital found that about half of the 16 deaths from Jan. 1, 1997, to March 12, 1998, were apparently due to contamination from the long fingernails.

No deaths from the bacteria have been reported since the hospital imposed measures like requiring that nurses in the neonatal intensive care unit have short nails, Dr. William R. Jarvis, head of the hospital infections program at the Centers for Disease Control and Prevention, said in an interview.

The infections were caused by bacteria known as Pseudomonas aeruginosa. The ubiquitous bacteria like moist environments and find their way into respirators and similar devices in hospitals.