Clinical and immunological characteristics of bee venom hypersensitivity among beekeepers in Thailand.

Background: Bee venom (BV) hypersensitivity can be severe and potentially life-threatening. Beekeepers heavily exposed to bee stings and are thus at a high-risk group. The data on bee sting reactions among beekeepers in Thailand is limited.
Objective: To determine the prevalence, clinical and immunological characteristics, and the knowledge of BV hypersensitivity in Thai beekeepers.
Methods: A self-reported questionnaire survey about BV reactions in beekeepers were conducted. Further blood test for immunological parameters: serum BV-specific IgE (BV sIgE), phospholipase A2-specific IgE (Api m1 sIgE), and BV-specific IgG4 (BV sIgG4) were compared between non-allergic beekeepers, patients with a history of bee sting anaphylaxis and the non-allergic control group.
Results: A total of 202 out of 447 questionnaires (response rate 45%) were returned. The median age was 46.7 years. Systemic reactions were documented in 6.4%. Younger than 45 years was found to be a factor associated with systemic reactions (OR, 4.35; 95% CI, 1.16-16.31). The BV sIgE and Api m1 sIgE were significantly higher in the anaphylaxis group (p = 0.001). The median of BV sIgG4 was significantly higher in non-allergic beekeepers (p = 0.001). For the knowledge of BV hypersensitivity, 56.4% recognized that BV hypersensitivity could be fatal but only 6% knew about epinephrine auto-injector device.
Conclusions: The prevalence of systemic reactions after stings among Thai beekeepers was not high, which might be due to the tolerance induced by natural exposure via sIgG4. The level of knowledge of BV hypersensitivity among beekeepers was insufficient, more education must be provided.