Introduction: Snakebite envenomation is a significant global health challenge, with Vipera berus being a primary species of medical concern in Europe. Despite traditional views of its venom as relatively mild, emerging evidence indicates substantial regional variability in toxicity and clinical manifestations. Purpose: This rapid narrative review synthesizes evidence regarding the biochemical and clinical variability of V. berus venom in Southeast Europe, specifically focusing on populations in Bosnia and Bulgaria. Methods: A qualitative narrative synthesis was conducted based on 12 core studies published in English up to January 2025, identified through PubMed and Google Scholar. Results: Findings reveal a distinct divergence: Bosnian V. berus bosniensis populations exhibit significant neurotoxic potential (affecting ~20% of cases), while Bulgarian populations show higher Phospholipase A2 (PLA2) activity and more frequent hematological disturbances (~30% of cases). Conclusion: The observed variability underscores the need for region-specific clinical guidelines and improved antivenom strategies. Future research must prioritize large-scale proteomic profiling and clinical trials to enhance the management of adder envenomation across Eurasia.
Jan-Peter Nilsson (2026) studied this question.