Background: Larvae of insects and worms are commonly used as live fish bait (LFB) by anglers. Asthma, rhinoconjunctivitis, and urticaria related to various kinds of LFB have been reported.
Methods: We studied 14 subjects with respiratory symptoms associated with exposure to LFB. Skin prick tests and RASTs with Lucilia caesar, Galleria mellonella, and Tenebrio molitor extracts were carried out in all subjects. Monitoring of peak expiratory flow rate and evaluation of bronchial responsiveness to methacholine before and after exposure to LFB were performed in seven subjects.
Results: Thirteen subjects had asthma, all 14 had rhinoconjunctivitis, and three had contact urticaria. Eleven subjects had respiratory symptoms after fishing with LFB, and the other three subjects had symptoms during their work in a commercial fish bait farm. Positive skin prick test results or significant RAST binding to L. caesar extract were observed in 13 subjects, to G. mellonella extract in four subjects, and to T. molitor extract in three subjects. After exposure to LFB, two subjects had an early asthmatic response, three had a late asthmatic response, and two had no asthmatic response. Late asthmatic response was associated with a long-lasting increase in bronchial responsiveness.
Conclusions: This study demonstrates that emanations from LFB are sensitizers, which have the potential to elicit IgE-mediated asthma. Exposure to LFB is common and LFB should be considered as a possible sensitizing agent for asthma.