One of the 12 critically burned survivors of last weekend's jumbo jet crash has developed an infection which "worsens" the patient's condition, doctors at Brooke Army Medical Center said yesterday.

Dr. Richard Treat, who would not identify the patient because of the federal privacy act, said three of the patients remained in bed in intensive care, but that nine were "up and around."

"One of the patients on the very seriously ill list developed an infection," Treat said. "This is being treated. However, development of an infection worsens the condition of the patient."

Meanwhile in San Francisco, a lawsuit was filed in federal court on behalf of victims in the worst aviation crash in history.

Filed as a result of Sunday's disaster at Santa Cruz de Tenerife in the Canary Islands where two 747s collided killing 577 persons, the suit -- if certified by the courts as a class action --wards for the survivors and relatives of victims, an attorney said.

The suit was filed on behalf of Harold E. McClintock, of Placerville, Calif., son of Myrtle E. McClintock who was killed in the crash, and David Nelson Roman, of Sunnyvale, Calif., son of Ruth Roman who also died.

It named Pan American World Airways, KLM Royal Dutch Airlines and Boeing Corp. as defendants. The suit alleged negligence and carelessness. It also alleged that the 747 planes were unsafe because of defects.