Insight into the Toxicological and Pathophysiological Effects of Moroccan Vipers' Venom: Assessing the Efficacy of Commercial Antivenom for Neutralization.

Morocco is one of the richest countries in biodiversity in the Mediterranean region, especially in its ophidian fauna. In total, there are eight species of venomous snakes, with seven belonging to the Viperidae family, responsible for 67.2% of severe envenomation cases in the country. , and are considered among the most venomous vipers whose bites cause high levels of morbidity, disability or mortality. Despite their wide distribution in the kingdom, the incidence of these snakebites remains poorly understood and largely underestimated. Moreover, intraspecific variations in the venom composition significantly affect the effectiveness of antivenoms. Due to the unavailability of locally produced antivenoms, we evaluated the efficacy of , the only available antivenom in Morocco, against , and First, we conducted a comprehensive characterization of these venoms, including an LD test to examine their toxicity and SDS-PAGE as a technique to analyze the enzymes responsible for biological activities, such as hemorrhagic and edematous activities and myotoxicity, which generate physiopathological effects in the skin, paws and muscles of envenomed mice. Then, we assessed the ability of antivenom to neutralize the toxic activities of Moroccan vipers. Our results indicate that the venom of , and are toxic, causing severe alterations such as edema, myotoxicity, myonecrosis and significant hemorrhages with the formation of hemorrhagic foci. venom is more dangerous in terms of lethality and hemorrhages, while venom is more edematous. The effects of venom were effectively neutralized, but antivenom failed to protect mice against the toxic effects induced by and venom. The study reveals alarming shortcomings in the effectiveness of the current commercially available antivenom's dosage and neutralization capabilities, highlighting the urgent need to develop a region-specific viper envenomation therapy.