Wasp
There are more than 25,000 species of wasp in the world, and the venom of each species differs in its composition. The composition of individual species' venom is still largely unknown. But generally, the compounds that cause pain when you're stung aren't toxins as such, but instead combinations of proteins, peptides and neurotransmitters that cause unpleasant reactions and immune responses in the victim of a sting. The discomfort doesn't last too long for most people, but a small percentage will experience severe and potentially dangerous reactions if stung.
Pain is the Point
Stinging is a defense mechanism in wasps. Trying to avoid pain is a defense mechanism in humans. Stings hurt because that's what nature has intended--they're a mechanism for wasps to scare off potential predators (or immobilize them if they're small enough to eat), and for sting victims to register a pain reaction that tells them in no uncertain terms that they'd best flee the scene. To that end, the venom of a wasp is a made-to-order combination that affects the human body on several fronts at once.
Cells Affected
Red blood cells
The compounds found in wasp and bee venom cause varying reactions in your body when you're stung. The peptide melittin, a key toxin in bee venom, binds to red blood cells and instantly creates a pain sensation. The neurotransmitter norephedrine slows blood flow, which means the venom lingers at the site of the sting longer and sustains the painful feeling. Your body reacts by sending fluids to the site of the sting to dilute the toxins, which in turn leads to swelling.
Role of Pheromones
Wasps deliver significantly less venom per sting than bees do--typically 2 to 15 micrograms, compared to 50 micrograms for bees. But wasps have a couple of secret weapons that ultimately give them the edge. First, their stingers don't tear off in the skin of their victims, so one wasp can sting you multiple times. (Bees, on the other hand, usually die after one sting.) More notably, wasp venom contains a pheromone that summons other wasps in the area, an alarming development for the hapless victim.
Allergic Reactions
The pain of a wasp sting is relatively short-lived for most humans. However, a small percentage of the population experience a severe and potentially life-threatening allergic reaction marked by hives, shortness of breath and a drop in blood pressure. These severe reactions occur in people who have been stung in the past with the same insect venom and developed antibodies. While rare, allergic reactions can occur even among people who have never shown an adverse reaction to previous stings.
Toxic Reactions
Unlike the life-threatening immune response that happens when you have an allergic reaction to a wasp sting, a toxic reaction is the result of an overload of venom from multiple stings at once. People who experience a toxic reaction are at greater risk of an allergic reaction from subsequent stings.
Tags: allergic reaction, wasp sting, blood cells, defense mechanism, experience severe, experience severe potentially