Envenomation by Vipera aspis in Piedmont (Italy): A report of three cases, including one case with neurological symptoms

This report describes three cases of human envenomation by the asp viper (Vipera aspis) in Piedmont, north-west Italy. A woman was bitten on the ankle while she was hiking and two herpetologists received bites on the hand while they were manipulating the animals. In the first case, the victim presented severe systemic symptoms (abdominal pain, vomiting, diarrhea) that required treatment with two vials of antivenom and hospitalization for one week. In the second case, the patient manifested neurological symptoms (blepharoptosis, ophtalmoplegia); he was treated with antivenom and discharged after five days. In the third case, the patient was bitten by a juvenile viper and showed only local symptoms (edema and bruising). All patients reported prolonged functional impairment after discharge from hospital. Although uncommon, envenomation by Vipera aspis can cause severe consequences that require immediate management and antivenom administration. These cases highlight the importance of obtaining better knowledge of the intraspecific variability of venoms and its clinical significance, as well as of the factors that determine the severity of snakebite injuries.