Black-tailed hornet possesses a stinger that delivers venom containing neurotoxins and cytotoxins. The sting can cause pain, swelling, and redness, with severe cases leading to muscle damage or renal failure. Typically, encounters result in mild symptoms, yet repeated stings or a high volume of venom could result in serious health complications.

Black-tailed hornet uses its venomous hairs as a defense mechanism. When touched, these hairs can release toxins causing mild to severe reactions in animals such as humans, dogs, cats, and birds. The larvae and adults of black-tailed hornet both possess these toxic hairs, which can deter predators and inadvertently affect curious humans or pets who might come into contact with them.

Black-tailed hornet typically sting humans in defense, particularly if their nests are disturbed or they feel threatened. They use their stinger to inject venom, causing pain and allergic reactions in some individuals. Unlike bees, black-tailed hornet can sting multiple times without dying, as their stinger is not barbed. While males cannot sting, females wield this defense, and repeated stings can have increased health implications for the victim.

The troubles black-tailed hornet bring to humans can be traced back to their nesting and defensive behaviors. These insects often nest in proximity to human habitats and may aggressively defend their territory. Encounters with humans typically occur when nests are disturbed or when black-tailed hornet feels threatened, especially since they are lured by human foods and can sting multiple times, leading to painful reactions and sometimes severe consequences.

Effective prevention against black-tailed hornet includes minimizing attractants such as open garbage, food waste, and strong odors. Securing trash bins and covering food during outdoor activities are practical steps. Construction of physical barriers and professional removal of nests can greatly reduce the risks. Use of proper clothing and netting when in areas with high black-tailed hornet activity is advised as a preventative strategy.

If an encounter with black-tailed hornet occurs, calmly and quickly leaving the area minimizes the risk of stings. In case of a sting, washing the affected area with soap and water and applying a cold compress can alleviate symptoms. Minimize physical exertion to prevent venom spread. During recovery, it's crucial to keep the sting area clean and monitor for signs of increased reaction. If severe symptoms develop, seek professional assessment. Always avoid disturbing suspected black-tailed hornet nests, and engage professionals for safe removal.

Black-tailed hornet often invades human habitats attracted by foods. Adult stages can inflict painful stings when threatened, causing distress. They may exhibit aggressive behavior, particularly near their nests, potentially leading to severe nuisance in human-dominated areas.