Tolerance in Beekeepers

Beekeepers experience multiple bee stings each year. Many of these beekeepers (25-60%) become sensitized to bee venom through the production of specific antibodies that target the bee venom. Although these antibodies are important in the triggering of an allergic reaction only a small number of sensitised beekeepers go on to have an allergic reaction with symptoms away from the site of the sting. These reactions can be severe and are known as anaphylactic reactions. The study investigates why some beekeepers develop severe allergic symptoms after bee stings while others do not. This study will explore factors in the blood that protect sensitised individuals from having anaphylactic reactions - meaning that despite being sensitised they are tolerant and do not react to subsequent stings.

Inclusion Criteria: \- Group 1 inclusion criteria. * Individuals naive to beekeeping (\ approximately 10 stings/year who have been beekeeping for \>3 years. * No history of anaphylaxis to bee venom. Group 3 inclusion criteria * Beekeepers with diagnosis of anaphylaxis to bee venom in the last 12 months who are sensitised to bee venom (as evidenced by positive specific IgE and positive skin test to bee venom) Exclusion Criteria: * Unable to understand protocol/consent. * Unable to commit to follow up visits. * Participants with a known history of mastocytosis or under investigation for suspected mastocytosis. * Participants undergoing desensitisation treatment to bee venom before the first visit. * Participants being treatment with immunosuppressive medications. being treatment with immunosuppressive medications.