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UKRI priority funding for 'Germ Defence' app to help reduce worldwide COVID-19 spread

Press release issued: 17 April 2020

UK Research and Innovation (UKRI) has announced priority funding for 'Germ Defence' - the only digital behavioural infection control intervention worldwide. Proven to reduce the transmission of infections in the home, clinicians and researchers from the Universities of Southampton, Bristol, Bath and Public Health England will now develop the resource into a freely available worldwide app in 20 languages.

It is well known that the public play a crucial role in infection outbreaks by adopting simple behaviours - such as handwashing, cleaning surfaces, mask wearing and social distancing - to curb the spread of infection.

By slowing the spread of infection, these behaviours can prevent everyone becoming ill at once, helping healthcare systems to cope until a vaccine is developed.  However, despite public health advice, evidence shows most people need help to change their behaviour to help prevent infection as much as possible.

Germ Defence will supplement public health advice by employing behaviour change techniques which can only be provided by an interactive app. The resource helps users with pre-planning for how to isolate an infected household member as far as possible; personalised goal setting for increasing a range of infection control behaviours; changing the home environment to support new habits and problem solving to overcome barriers.

Developed during the H1N1 pandemic using theory, evidence and extensive feedback from members of the public. Germ Defence was then trialled in over 20,000 patients, and shown to reduce the number and severity of infections of users and members of their household (this trial was published in The Lancet).

Using the latest evidence for the COVID-19 outbreak, the £200,000 UKRI funding will enable researchers and clinicians, alongside patient representatives, to study how best to adapt the app to meet users' needs in different countries, by evaluating how it is used and its effects on infection control behaviour, with the aim of making it freely available worldwide.

Study lead Professor Lucy Yardley, from Bristol's School of Psychological Science, said: "Most people think that if a family member gets ill then it is just a matter of luck whether other people in the household get infected – but our trial of Germ Defence has shown that it is possible to protect the people you live with from also getting ill.

"In the first week it was made available, with very little publicity, Germ Defence was accessed over 10,000 times and frequently shared on social media. It is now being translated into nearly 20 languages so it can be used internationally. We hope the app will save lives by helping people avoid spreading coronavirus to family members."

Germ Defence is freely available at

Further information

Germ Defence is one of 21 new studies into the novel coronavirus which have been funded by the UK government, including the first clinical drug trial in primary care, vaccine and therapy development, and studying epidemiology, disease transmission, behavioral interventions and policy approaches to COVID-19.   

This second round of projects receive £14.1 million as part of the £24.6 million rapid research response funded by UK Research and Innovation (UKRI), and by the Department of Health and Social Care through the National Institute for Health Research (NIHR).    

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