The ACACIA study (Achieving Control of Asthma in Children In Africa) is a £2 million study run by a group of researchers based across Africa and the UK. It has been designed to understand and improve the health of young people with asthma in Africa. The number of young people with asthma has been rising dramatically in many African countries over the last two decades, yet there has been little research into this and the difficulties these children may be facing in managing their condition.

"Children in sub-Saharan Africa are increasingly developing diseases of urbanisation, such as asthma," says Professor Jonathan Grigg from Queen Mary’s Blizard Institute, and Director of the NIHR Global Health Research Group. "Working with leading paediatricians across Africa, the ACACIA study will allow us to describe the burden of asthma in children, and the reasons underlying poor asthma control.”

The CAPPA project is an extension to the ACACIA initiative, which aims to describe the burden of personal air pollution exposure in urban children with asthma symptoms in sub-Saharan Africa, its geographic, and temporal variability, the role of transport, indoor and outdoor microenvironments and activity profiles, and the effect of socioeconomic variables.

“What is so beneficial about the Dyson air monitoring backpacks is that they collect data on personal exposure; they tell you what that individual is breathing in, minute by minute," says Alex Knox, VP of Engineering, Environmental Care at Dyson. "By reworking the sensing technology from our in-home purifiers, we can be confident the gas and particle pollution readings are highly accurate so we can provide the research teams with the robust, meaningful data they need to build the scientific evidence and ultimately better understand the global solutions.”

Dyson’s air quality monitoring backpack will be carried by 420 of the school children participating in the ACACIA study, aged between 12 and 15 years of age. Data collection for each child will last for five days in urban settings across the seven participating countries: Ghana, Malawi, Nigeria, South Africa, Tanzania, Uganda and Zimbabwe. Dyson’s air quality backpack, which was developed for the Breathe London: Wearables study with Kings College London and the Greater London Authority, has on-board sensors, a battery pack and GPS, allowing data to be collected on the go. Re-working existing sensing technology used in Dyson air purifiers, engineers designed the portable air monitoring device, engineering it to be smaller, lighter, and more portable, whilst still accurately capturing PM2.5, PM10 and VOC and NO₂ exposure.

Similarly to the Breathe London: Wearables Study that was conducted with school children in London, QMUL and Imperial researchers will analyse personal air pollution data collected by the Dyson backpacks for exposure patterns. They will compare air pollution as well as activity profiles of children in relation to their socioeconomic and geographical backgrounds both within and between countries. Additionally, the research teams will carry out lung function testing using spirometry and collect further information about children’s environmental exposure and symptoms in a survey to explore connections between air pollution exposure and lung health in these children. Results will be contrasted with similar measured data from school-age children in London arising from the Breathe London: Wearables study.