Germ Defence  [freely available from www.germdefence.org/] is the only web-based advice in the world that has been scientifically proven to work against respiratory infections. In a Lancet study of over 20,000 people, using Germ Defence reduced the spread of swine flu and seasonal flu in the home.

Germ Defence provides personalised advice on how to protect everyone in the household from infection.  The website has been updated for Covid-19 by a team of health researchers at Bristol, Southampton and Bath universities, working with members of the public and Public Health England, and with funding from National Institute for Health Research (NIHR) and UK Research Institute (UKRI).

Earlier this month Germ Defence reached the milestone of the first 100,000 users, who gave it an average rating of eight out of ten for usefulness.

Professor Lucy Yardley, who led the development of Germ Defence and is Theme Lead for the NIHR Health Protection Research Unit in Behavioural Science and Evaluation at the University of Bristol, said: "Many people don’t realise that there are simple things they can do that will really reduce the risk of virus in the home. Germ Defence can help everyone and includes advice on what to do if someone in the household may be infected, or could become very ill if they are infected."

Dr Jeremy Horwood, Associate Professor in Social Sciences and Health  from NIHR Applied Research Collaboration West (ARC West) at the University of Bristol, added: "The updated Covid-19 version of Germ Defence helps people understand what measures to take in the home and how to adopt habits that will help to avoid infection.  By rolling out Germ Defence we hope it could help save lives by reducing the spread of the Covid-19."

Dr Ben Ainsworth, from the Department of Psychology at the University of Bath who is leading the adaptation of Germ Defence for Covid-19, explained: "The advice in Germ Defence has been tested with help from many public volunteers, working together with scientists, doctors and health experts, to make sure the advice and tips are as understandable and useful as possible. It’s available in more than 25 languages and is constantly updated as new scientific evidence and research comes out."

Sascha Miller, who has been working with members of the public to make sure the advice is useful to them, said: "With winter and Christmas coming, we know that people are keen to learn how to make their home as safe as possible for all the family. Germ Defence provides practical advice on things like ventilation and social distancing to help people spend time together."

Cathy Rice, a member of the public who is part of the Germ Defence team, added: "It's easy to feel overwhelmed when trying to protect ourselves and our families against Covid-19, but Germ Defence gives simple steps that really work. It only takes 10 minutes, it’s backed up by science, and it’s something everyone can do. Go to it!’"

Anonymous feedback from users includes:

• Good website, simple clear and easy to understand.
• It was very easy to follow, broken up into sections, and interactive which also helps.
• I have found your 'germ defence' pages very useful thought provoking.
• Gives people positive thing to do to keep themselves and their families safe.
• It reinforces easy ways that most of us can do to reduce infection.
• I am a family carer and sent the link to both my mother who is shielding and my 23-year-old son... he has been watching my efforts over the past weeks. He won’t be told anything by me, so your website is a great way to get the message across.