Tuscany, May 11 -- A 23-year-old woman from Italy on Sunday was mistakenly given six doses of the Pfizer BioNTech COVID 19-vaccine.

A health worker at the Noa hospital in Tuscany, central Italy accidentally filled a syringe from a whole bottle of the vaccine which contains a total of six doses.

She noticed her mistake when she saw five empty syringes on the side.

An internal investigation has been opened by the hospital as the patient was an intern in the hospital's psychology department.

"It was maybe just human error, definitively not on purpose," Danielle Gianelli, a hospital spokesperson told CNN.

The patient has been discharged from the hospital after being under strict observation for 24 hours, "but the doctors will continue to...