A 20-year-old woman started working as an animal house technician. She dealt mainly with rodents and was given minimal training.. A few months later, she developed runny glazed and gritty eyes, stuffy, itchy, and runny nose (rhinitis). She also had wheeze, tightness of chest, and shortness of breath which improved on spells away from work. When the rodents scratched her, she noticed that her skin very quickly developed raised red patches.

Her general practitioner prescribed treatment with bronchodilators, producing slight improvement, but her symptoms persisted. After about one year in employment, she experienced an episode of angioedema and had serious difficulty with breathing. She was seen in a hospital casualty department and treated with adrenaline and hydrocortisone. However, no specific action in relation to her job was considered. After this episode, she did not resume the job…