Anna Larson was a 94-year-old resident of St. Petersburg, Florida, who was injected with a large quantity of insulin at the North Horizon Health Center on November 16, 1984. The overdose required hospitalization; she survived the insulin injection but died in January 1985 of causes described as unrelated to that injection. She was one of several elderly patients targeted during a two-week span in which twelve residents died under suspicious circumstances.

Authorities charged 33-year-old registered nurse Bobbie Sue Dudley with attempted murder in Larson’s case. Dudley began working at the facility in early October 1984; investigators found a five-page document under her mattress listing deceased patients by bed number and time of death. Dudley later pleaded guilty to second-degree murder in the deaths of four other elderly female patients and to attempted murder in Larson’s case, and received concurrent sentences.

The case highlights failures in oversight at the nursing home and prompted inquiries into other facilities where Dudley had worked.