House-dust mites : challenges with establishing causal associations in occupational health for ubiquitous agents - a retrospective study

Abstract

In this retrospective study, the sensitisation profiles of 846 workers (≥18 years old) were tested with house-dust mite (HDM) allergens and other common aeroallergens for the ten-year period 2002–2022. This study aimed to determine the proportion of HDM sensitisation among workers from various industries and to highlight the role of HDM exposure and current developments in occupational settings. Exposure to HDM allergen can occur in both households and work environments. Dermatophagoides farinae and Dermatophagoides pteronyssinus are the most commonly distributed dust mites worldwide. Inhaling allergens produced from these mites can result in respiratory symptoms, rhinitis and asthma in sensitised individuals. Exposure to these allergens in the workplace may result in occupationally acquired or workaggravated allergic reactions, leading to poor quality of life, an increase in absenteeism arising from sickness and, consequently, reduced productivity. The percentage sensitisation among workers referred to the NIOH Occupational Allergy clinic was 41.67% for D farinae and 33.81% for D pteronyssinus. Nineteen per cent of the patients who reported work-related symptoms tested positive for HDM; therefore, work-related sensitisation is plausible. While Blomia tropicalis was not tested in the current study, it may be beneficial in tropical areas.