EXPLORING THE FEASIBILITY OF OCCUPATIONAL ALLERGY SURVEILLANCE USING ROUTINE PUBLIC-HEALTH DATA: A RETROSPECTIVE ANALYSIS

This retrospective study aimed to assess allergic sensitisation among adult patients tested at National Health Laboratory Service (NHLS) laboratories across nine provinces in South Africa. With a primary focus on identifying prevalent allergens, the investigation extends to comparative analyses with workers tested at the National Institute for Occupational Health (NIOH) and explores trends during a ten-year period from 2012. The overarching objective was to ascertain the potential value of leveraging routine public-health data for comprehensive occupational allergy (OA) surveillance, attempting to fill a critical gap in existing South African OA data. In examining allergic sensitisation, the study spanned NHLS laboratory tests conducted from January 2012 to December 2021, encompassing adult demographic ages from 18 to 65 years, which represent the typical working age of South Africans. The results for allergens recommended by the South African Allergic Rhinitis Working Group and other allergens of relevance in occupational settings were extracted and analysed, providing a robust foundation for a nuanced exploration of sensitisation patterns. Of the 31 913 NHLS laboratory records, 48.48% of adults tested positive for ImmunoCAP Phadiatop, indicative of atopy. In addition, the percentage sensitisation to common aeroallergens of 538 workers tested at the NIOH using the skin-prick test method was compared to those of patients tested at the NHLS. Furthermore, the study uncovered a spectrum of sensitisation patterns, with house-dust mites and grass pollens emerging as predominant allergens. Occupational allergens, including latex, alpha-amylase and chlorhexidine, manifested as noteworthy contributors to sensitisation, shedding light on potential workplace hazards. Provincial variations in sensitisation patterns underscore the nuanced nature of allergic responses across different regions. Dermatophagoides pteronyssinus dominated in five provinces, signifying geographical disparities in allergen prevalence. Intriguingly, comparison with NIOH data reveals significantly higher sensitisation rates in NHLS patients for specific allergens, which suggests potential variations in testing methodologies and patient selection between the two institutions. Drawing from these insights, the study concluded that routine NHLS data are of critical importance for trend analysis and preventive strategies. The high prevalence of sensitisation to common allergens underscores the imperative for targeted preventive measures. This study, bridging the gap in OA data, lays the groundwork for future research exploring the intricate associations between routine allergen sensitisation testing and OA surveillance.