A grant from the Health Research Council will enable researchers to assess why biodiversity may reduce allergy and asthma risks in children.
Massey University’s Centre for Public Health Research director, Professor Jeroen Douwes, has been awarded close to $1.2 million to carry out research over the next four years to help understand how exposure to the natural environment may protect against asthma and allergies, and identify what aspects of biodiversity provide the most protection.
Professor Douwes said this is particularly important in light of the excessive decline of biodiversity observed in the past few decades, which has coincided with a rapid increase in the prevalence of allergies and asthma globally.
In a previous research project, Professor Douwes and colleagues assessed the association between the natural environment and asthma in 49,956 children born in New Zealand in 1998, who were followed until they were 18 years old. Researchers used satellite imagery and land-use data to assess children’s lifetime exposure to the natural environment and vegetation types.
“In that study, we showed that biodiverse green space was associated with a reduced risk of asthma. We hypothesise this may be due to increased environmental and human microbial diversity, which have been shown to direct the immune system away from developing allergies and asthma.”
The new study will involve 900 urban children from Wellington and will, for the first time, assess whether biodiversity reduces allergy and asthma risks through differences in exposure to microorganisms in the environment and the gut.
The study will also investigate the specific immune responses involved, while taking into account the effects of nutrition, physical activity and stress.
Participating children will undergo lung function and skin prick testing, and they will be asked to provide a blood and faecal sample. Dust samples will be collected from their home and the children’s schools.
“The overall objective is to increase our understanding of modifiable causes and mechanisms of allergies and asthma, enabling the development of novel and targeted interventions. Going forward, this research could help inform urban design with the aim of reducing the global burden of childhood asthma,” Professor Douwes says.
The study, 'Biodiversity and microbiota – a novel pathway to allergy and asthma prevention', will be carried out over four years, and begins in September. It will be conducted in collaboration with researchers from the University of Otago; Flinders University, Adelaide, Australia; and the United States Department of Agriculture Forest Service, Portland, United States.