The study revealed that older adults and young children are more vulnerable during periods of high air pollution.
Analyses of invasive pneumococcal disease (IPD) in South Africa have found that air pollution can trigger deadly infections. Photo: iStock
Analyses of invasive pneumococcal disease (IPD) in South Africa found that air pollution can trigger deadly infections, changing the risk and timing of pneumonia, sepsis and meningitis depending on the bacterial subtype a person carries.
The study, which will be published in Nature Microbiology on Monday, 14 September 2026, was conducted by the Wellcome Sanger Institute, the National Institute for Communicable Diseases (NICD), the Barcelona Supercomputing Centre, and collaborators.
South Africa
It analysed 59,000 cases of invasive pneumococcal disease (IPD) across 19 years from South Africa’s GERMS‑SA surveillance programme.
Researchers found that different Streptococcus pneumoniae (S. pneumoniae) subtypes responded differently to air pollution exposure. Subtypes 14, 19A and 8 were linked to the greatest risk of IPD following exposure, while subtypes 4, 8, 23F and 19F were associated with an immediate rise in cases within the same week.
Adults and children
The study also revealed that older adults and young children are more vulnerable during periods of high air pollution, and that improving air quality could lower disease risk.
Professor Anne von Gottberg, co‑senior author at the NICD, said invasive pneumococcal diseases are a significant public health issue in South Africa and globally.
“This research adds to the ongoing evidence that air quality greatly impacts our health and shows that it has different effects depending on the strain of bacteria that is found in an area.
“We need to focus on monitoring and improving air quality in areas with high disease risk to prevent or reduce some of these infections,” von Gottberg said.
Climate change
Professor Rachel Lowe, co‑senior author at the Barcelona Supercomputing Centre, added that climate change and rapid urbanisation are fundamentally altering the environmental conditions that influence the risk of infectious disease.
“By linking long‑term climate and air quality monitoring with health outcomes, this work highlights how shifting environmental patterns can amplify public health risks.”
Dr Sophie Belman, first author, explained the role of bacterial subtype in shaping infection risk:
“While we found that temperature and air pollution generally increase the risk of invasive pneumococcal diseases, such as bacterial meningitis, our research also suggests that it is the bacterial subtypes a person is carrying that modulate infection rates.
“The strain of bacteria impacts the timing of disease and who might be more at risk depending on their respiratory microbiome,” Belman said.
Environmental monitoring
The authors suggest that integrating environmental monitoring with genomic surveillance of S. pneumoniae could help predict infection spikes, inform vaccination strategies, and support hospitals during periods of poor air quality.
The findings also provide further evidence that reducing air pollution may yield important benefits for infectious disease prevention, particularly in urban areas with high exposure.
Air pollution
The World Health Organisation (WHO) previously warned that 99% of the world’s population is breathing polluted air that exceeds internationally approved limits, with negative health impacts kicking in at much lower levels than previously thought.
WHO said a record 6 000 cities in 117 countries now monitor air quality, but people living there still breathe unhealthy levels of fine particulate matter and nitrogen dioxide.
