Airborne fungal spores and pollen (aerospora), synergistic with air pollution, are key triggers of allergic respiratory diseases. Effective diagnosis and treatment requires up-to-date location-specific knowledge on the temporal variability of aerospora types and levels. Johannesburg is the largest city in South Africa and has grown substantially in three decades, with changes in ground cover, population density and air pollution, yet until now, no continuous aerospora sampling has occurred. We present a daily two-year (August 2019–July 2021) aerospora assemblage for Johannesburg and explore temporal characteristics of 13 dominant aerospora in relation to daily meteorological variables (pressure, rainfall, relative humidity, temperature and wind characteristics). February–July, July–September and January-July represent high-risk periods for fungal spores [(Alternaria alternata (Fries. ex Keissler), Ascospores, Aspergillus niger (Van Tieghem), Penicillium chrysogenum (Thom), Cladosporium graminum (Corda), Epicoccum nigrum (Link), Helminthosporium solani (Durieu and Montagne) Nigrospora sphaerica (Saccardo ex. Mason), Smuts Ustilago nuda (Jensen ex. Rostrup) and Torula herbarum (Link)], trees (Cupressus, Morus and Platanus) and grass (Poaceae), respectively. Using a generalised additive model, results show that daily meteorological characteristics explained 7–32% of daily aerospora variability, with the largest effect on tree pollen. Rainfall, relative humidity and temperature influenced daily fungal spore and Poaceae counts, with moderate/low rainfall (< 20 mm), higher/mid-ranging relative humidity (~ 40–60%) and temperatures of ~ 15–20 °C associated with higher counts during high-risk periods. Rainfall predominantly influenced tree counts during high-risk periods, with higher counts occurring on low rainfall (<10 mm) days. These results update the aerospora profile of Johannesburg, South Africa, providing important information to inform allergy care.

Background: Pollen monitoring has been discontinuously undertaken in South Africa, a country with high biodiversity, a seasonal rainfall gradient, and nine biomes from arid to subtropical. The South African Pollen Monitoring Network was set up in 2019 to conduct the first long‐term national aerospora monitoring across multiple biomes, providing weekly reports to allergy sufferers and healthcare providers.Methods: Daily airborne pollen concentrations were measured from August 2019 to August 2021 in seven cities across South Africa. Updated pollen calendars were created for the major pollen types (>3%), the average Annual Pollen Index over 12 months was calculated, and the results were compared to available historical data.Results: The main pollen types were from exotic vegetation. The most abundant taxa were Poaceae, Cupressaceae, Moraceae and Buddleja. The pollen season start, peak and end varied widely according to the biome and suite of pollen taxa. The main tree season started in the last week of August, peaked in September and ended in early December. Grass seasons followed rainfall patterns: September–January and January–April for summer and winter rainfall areas, respectively. Major urban centres, for example, Johannesburg and Pretoria in the same biome with similar rainfall, showed substantive differences in pollen taxa and abundance. Some major differences in pollen spectra were detected compared with historical data. However, we are cognisant that we are describing only 2 years of data that may be skewed by short‐term weather patterns.Conclusions: Differences in pollen spectra and concentrations were noted across biomes and between geographically close urban centres. Comparison with historical data suggests pollen spectra and seasons may be changing due to anthropogenic climate change and landscaping. These data stress the importance of regional and continuous pollen monitoring for informed care of pollinosis.

South Africa’s urban population is increasing, and in parallel, urban green infrastructure has shown an increase in alien tree species, e.g., mulberry (Morus sp.), oak (Quercus spp.) and plane trees (Platanus spp.) to name a few. This causes ecological problems since alien trees are often more water-demanding and competitive than indigenous trees, but they also increase the abundance of respiratory diseases often triggered by an allergic reaction towards the pollen of those alien taxa. In the current study, utilizing 7-day volumetric spore traps, we illustrate that the most abundant tree pollen in the two largest cities of South Africa, Cape Town and Johannesburg, is produced by alien trees with a high risk of allergenicity. This adds another aspect related to public health when evaluating plant species composition in urban forestry and urban ecology, which underlines the urgency of more intense monitoring. More importantly, this—for South Africa—newly emphasized risk for public health underlines the applicability of current directives [i.e., Spatial Development Frameworks (SDFs), localized Precinct Plans, Land Use Schemes (LUSs)] and implementation options in urban planning. Here, we present ideas that may be implemented in such a framework. From both a public health and an ecological perspective, it is recommended to plant indigenous trees like Combretum erythrophyllum, Vachellia and Senegalia spp. that have fewer ecosystem disservices, like a lower impact on public health due to lower allergenicity/lower pollen occurrence and providing more ecosystem services such as lower water needs.

Pollen monitoring is crucial for understanding seasonal patterns, supporting allergy diagnosis and informing early warning tools to mitigate allergic diseases. The Southern Hemisphere lacks long-term pollen seasonal data, with extremely few records from Africa. We present pollen calendars based on five years of data from South Africa. Airborne pollen from 2019 to 2024 across South African biomes was collected in seven cities using Hirst-type volumetric spore traps and standard protocols. Daily concentrations were analysed by light microscopy. The five-year mean annual pollen integral (APIn) were calculated for each site. The five-year mean APIn was highest in the Grassland Biome (Bloemfontein) and lowest in the Albany Thicket Biome (Gqeberha). The Grassland Biome (Johannesburg) had the highest average tree pollen integral, while the Savanna Biome (Kimberley) had the highest average annual grass pollen integral. The grass family (Poaceae ) was the most common pollen type across all biomes. Other common taxa were exotic trees Cupressaceae, Platanus , Morus and Betula . Tree seasons were July to September, while grass and weed pollen seasons varied across the biomes. These five-year pollen calendars provide the first biome-specific national reference for airborne pollen exposure in South Africa. The findings provide baseline data for the clinical management of allergic disease.

Native to Southeast Asia, the fly Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), or Spotted Wing Drosophila, has become a major pest of soft-skinned fruits in several countries globally. However, its distribution in sub-Saharan Africa was limited to Kenya and some Indian Ocean Islands. In 2021, an industry-funded surveillance project was initiated to determine whether the pest was present in the Western Cape and Eastern Cape provinces of South Africa. Trapping was conducted using lures developed for this species in bucket-type traps. The first D. suzukii detection was of a single male, trapped on the 25th of April 2022 in the Langkloof region in the Eastern Cape province. This research presents the first report of D. suzukii occurring within South Africa. We also present the results of ongoing surveys showing the current spread of the pest in South Africa.