Salt Lake businessman William E. Haast remained in serious but stable condition Friday in University Hospital, three days after being bitten on the left thumb by a deadly viper.

Because it was the 148th time a poisonous snake had bitten the 78-year-old owner of Miami Serpentarium Laboratories, Haast assumed he was immune to the snake. He didn't check himself into the hospital until 24 hours after the accident.John Dwan, hospital spokesman, said the snake expert was allergic to the antivenin available in Utah. The appropriate antidote was obtained from the San Diego Zoo.