The intersection between air quality aerobiology and asthma in South Africa - could green spaces help?

Abstract

Global and South African populations continue to increase exponentially, with large flows of persons into urban centres. Urban air quality and bioaerosol are therefore becoming an increasingly important consideration in the face of a growing burden of allergic respiratory diseases. More than 20% of South Africans have asthma, with morbidity being disproportionately high compared to high-income countries (HICs). Air pollutants (particularly particulate matter and ozone), pollen and fungal spores are known triggers and exacerbating factors in asthma and, alarmingly, the levels of air pollutants remain high in hotspot areas despite robust air-quality legislation in South Africa. The concern is that genetically and environmentally vulnerable children in low- and middle-income countries (LMICs) such as South Africa will have asthma triggered and exacerbated disproportionately by poor air quality. Urban green areas are increasingly being recognised by many stakeholders as important possible mitigation tools. However, multiple factors must be considered for having an optimal green space design. In this review, we bring together experts across the fields of health, air quality and aerobiology to outline the intersection between asthma and air quality and/or aerobiology in South Africa. We highlight the importance of careful multidisciplinary green space design as a possible healing tonic. We conclude that detailed studies combining air quality, pollen dispersal and health issues are needed to derive more precise exposure–response functions of the green spaces in South Africa and other LMICs.