Mosquito bite exposure results in a variety of reactions and secondary complications. Clinical hypersensitivity manifests primarily as local reactions with anaphylaxis being a very rare event. Risk factors for more severe local reactions include immunodeficiency, young children and visitors to an area with new exposure to indigenous mosquitoes. Necrotic skin reactions to mosquito bites have been associated with a newly recognized hemophagocytic syndrome in predominantly oriental populations. Diagnostic and therapeutic agents in the clinical management of mosquito hypersensitivity remain limited, but recent discovery of 3 recombinant proteins (rAed a 1, rAed a 2, rAed a 3) shared by several mosquito species promise to be more specific skin test antigens for the future.