Allergy to laboratory animals: a follow up study of its incidence and of the influence of atopy and pre-existing sensitisation on its development.

OBJECTIVES To investigate the incidence of allergy to laboratory animals (ALA) during the first two years of employment, and to study the effect on ALA of atopy and sensitisation. METHODS A follow up prospective study of ALA at the Zeneca (formerly ICI) Research Laboratories. RESULTS The incidence of the disease during the first year of employment has remained at about 10% since the mid-1980s. This compares with an incidence of 37% in the early 1980s. The reduction in incidence and its maintenance at a lower level is thought to be due to the introduction and management of improved engineering controls, working practices, and educational programmes designed to reduce exposure to allergens from laboratory animals. The underlying incidence of immunological sensitisation to animals (the presence of immunoglobulin E (IgE) antibodies to animal allergens) is much higher (40% after one and 53% after two years of exposure). Both atopic diathesis and presensitisation to laboratory animals increased the likelihood that a person would develop ALA. CONCLUSION Neither factor predicted the disease accurately so their use should be restricted to the identification of people who may be more susceptible to the development of ALA (and thus who may need to pay particular attention to the use of personal protective equipment) rather than to their exclusion.