Epidemiology of allergy to insect venoms and stings.

Stings by bees, yellow jackets, hornets or wasps may cause allergic reactions in sensitized individuals, including systemic or anaphylactic reactions. The epidemiology and natural history of insect venom allergy is emerging in the past decade and has clarified the reasons for the false perceptions that whole body extracts of the insects were considered effective for therapy. Up to 3% of adults have had a systemic sting reaction but 25% show venom sensitivity on skin test or RAST. Sensitization is common after a sting but is transient in 50% of cases. The risk (and pattern) of systemic reaction differs in children, but is 50% for those with positive history and skin test. Lower risk of reaction is expected in those with positive skin tests and large local reactions (5-10%), no previous reaction (10-20%), children with strictly cutaneous generalized reaction (1-10%), or for those with no stings for over ten years (15-25%). These observations have profound impact on the evaluation of patients for initiation or discontinuation of venom immunotherapy.