The ZOE COVID Study was created by doctors and scientists at the Harvard T.H. Chan School of Public Health, Massachusetts General Hospital, King's College London and Stanford University School of Medicine, working in partnership with ZOE – a health science company.

This app was built in the US to support studies like the Nurses’ Health Study. This is one of the largest and longest-running scientific studies in the world with 280,000 participants stretching back to 1976. Many participants in the Nurses' Health Study are still active healthcare workers who are treating people with COVID across the country and risking their own health to help us. We are also working with other studies across the US to collect data from their participants. The app is now available to anyone in the US or UK who wants to help.

The app will be used to study the symptoms of COVID-19 and track the spread of this virus. This research is led by Prof. Tim Spector, Professor of genetic epidemiology at King’s College London and director of TwinsUK; Prof. Andrew Chan, Professor of Medicine at Harvard Medical School, and Chief of the Clinical and Translational Epidemiology Unit at Massachusetts General Hospital and a physician-epidemiologist; and Prof. Christopher Gardner, Rehnborg Farquhar Professor of Medicine - at Stanford University Prevention Research Center.

Prof. Spector created and runs TwinsUK which is a scientific study of 15,000 identical and non-identical twins, which has been running for nearly three decades. As well as using the app to study symptoms in the general population, TwinsUK is using it to understand how symptoms develop with participating twins. Their research is funded by the Wellcome Trust and the National Institute for Health Research.

The research aims to help scientists understand COVID-19 and other major health conditions and illnesses, with the following specific aims:

• Better identify and understand symptoms of COVID-19
• Understand how vaccines affect the spread of disease and severity of symptoms
• Understand how long the protection of vaccines lasts
• Understand how fast viruses may be spreading in your area
• Identify high risk areas of disease in the country
• Identify who is most at risk by better understanding symptoms linked to health conditions
• If you opted-in to wider health studies or joined the study after 2nd September 2021, your data can be used to investigate a wide range of health conditions, including other infectious diseases, dementia, cancer, cardiovascular disease, and more, which helps ZOE in its mission to improve human health

• In the future, we hope we will be able to use this data to help health services support sick individuals. This app is not intended to be a diagnostic tool. For official advice about the coronavirus please visit the CDC website

If you are a member of the Nurses' Health Study based at Harvard Medical School and the Harvard TH Chan School of Public Health or another research cohort listed on the app then the following does not apply, and you should reference the special study consent you will sign.

Full details, including the institutions we are working with, can be found in our privacy policy.

A summary follows:

Your data is protected under "General Data Protection Regulation" (GDPR) which extends beyond the standard requirements of US data protection regulations. Under GDPR your data can only be used for the purpose that you consent to. That means it can only be used to help medical science and healthcare providers to better understand Coronavirus. This is a not-for-profit initiative, and no information you share can be used for commercial purposes.

We try to minimize the amount of personally identifiable information we collect (e.g. we ask for year of birth, but not date of birth, and zipcode, but not street address), while recognizing that the research does require some basic demographic info. This app is designed by researchers and physicians at Massachusetts General Hospital, Brigham and Women’s Hospital,  Harvard T.H. Chan School of Public Health, Stanford University, King's College London and Zoe Global Limited, a health data science company. They have access to all the information you enter.

We may share your data with other medical researchers. Before sharing any of your data with them, we will remove your name, phone number if provided, zipcode beyond the first three digits and email address to protect your privacy.

We take data security very seriously and enforce best practices to ensure your data is protected. This doesn't mean that there is no risk but we have taken every precaution to minimize that for you.

We are also required to protect your data by law. The “General Data Protection Regulation” (GDPR) applies to our processing of your personal data. GDPR extends beyond the standard requirements of US data protection regulations. You can read more about your rights under GDPR in our privacy policy.

No. This is a not-for-profit initiative. The app is and always will be free. The data you provide cannot be used for commercial purposes. While ZOE Global Ltd is a commercial entity, this app was built for free to support Massachusetts General Hospital, Harvard T.H. Chan School of Public Health, Stanford University and King's College London in their vital coronavirus research.

We may seek grants and donations in the future, to cover the costs of the service and so we can roll it out to the many countries who have been contacting us.

If you would like us to stop processing your personal data, you may withdraw your consent at any time by selecting 'Delete my data' from the main menu in the app or by visiting https://privacy.zoe.com/zoe. When you withdraw your consent, we will delete all personal data we hold about you.

Yes. We are working with researchers around the world, and this app reflects input from many countries. We expect the questions we ask to evolve as we learn more about the virus. King's College London will be working closely with Massachusetts General Hospital and Stanford University to coordinate data sharing with researchers and physicians in the UK, US and other countries to try and learn as fast as possible.

We are constantly reviewing the latest research and advice from scientists in order to include all relevant symptoms. If you are experiencing a symptom that is not currently listed in the app, then we now have an additional question that allows you to share this with us. You can do this by reporting for yourself, selecting 'I'm not feeling quite right', and adding your symptoms to the 'Other symptoms' field at the bottom of the page.

Yes. You are able to add multiple profiles on the app and report symptoms on behalf of someone else, provided that you have their consent to do so. Please ensure that your app is updated to the latest version in order to do this.

Yes. We have included new questions about previous exposure to COVID for new users only, including any symptoms that you experienced before you started reporting with the app, and when you experienced these symptoms. Please ensure that your app is updated to the latest version in order to do this.

Sharing your symptoms with others is not currently possible. We may make this feature available but as a small, not for profit team we appreciate your patience.

No one under 18 is able to use our app directly. However, as the parent or legal guardian of a child you can report on their behalf by adding them as an additional profile, provided that you follow the appropriate consent process as outlined in the app.

This is a not for profit app that was produced in a very short development time, therefore we admit there may be a bug or two. We welcome any and all feedback about our app in the relevant app store, or at covidtrackingquestions-us@joinzoe.com. Please bear with us as we resolve these issues.

We are aware some users have experienced issues creating an account on the app. This is a not-for-profit app that was produced in a short development time, therefore, there may be a few bugs. The number of users scaled from zero to 1.5 million within 48 hours. The good news is some of our team have built software that has scaled to hundreds of millions of users, but we still need to move fast to catch up! We recommend uninstalling and reinstalling the app and try creating an account again. If this doesn't work, please contact us at covidtrackingquestions-us@joinzoe.com. We are working on a better solution but this is a non-profit initiative, so please bear with us.

If you uninstall and reinstall the app, you will be logged out of the app and you can try to create a new account with the correct email address. We know this isn’t a long-term solution, but it is a short-term fix that we are using for now.

Our app will send you a notification towards the end of each day if you haven't reported how you are feeling that day, provided that you have notifications enabled in your phone settings. If you are unsure if you have notifications enabled, in the app menu, there will be a button labelled "Turn on reminders" where you can ensure your device settings are correct.

We are currently available in the USA, UK and Sweden. We hope to release to other regions in the near future, based on an open-source approach. If you are interested in supporting the app – through development skills, local language expertise, or other skills – please let us know by emailing research@joinzoe.com.

Although this is not currently available, we intend to do so as soon as we have the resources. We realize that it is important for those who do not have smartphones or are otherwise unable to use a mobile-based app.

We are aware that our app fails to meet some accessibility standards and are working to resolve these issues.

This feature is now available and can be viewed on our website here.

We use your email address so that if you lose your password we can send you a new one. You can use whatever email address you wish.

We are unable today to set any particular time limit on the storage of your sensitive personal data, but we will keep it under regular review and ensure that it is not kept longer than is necessary. Data about the spread of the virus is likely to be extremely valuable for researchers studying both this virus and in understanding epidemic spread for the future. We are likely, therefore, to retain this information for much longer.

If you are experiencing trouble logging in – please select 'Forgot your password?' at the bottom of the sign in screen, enter the email address that you used to sign up for the app, and we will send you a link to reset your password. Please ensure that you enter the same email exactly that you used when creating an account, as you will otherwise not receive a password reset link. If you have ever received one of our weekly emails, you can confirm the exact email you registered with by checking the 'to' address on that email. If this doesn't work, please contact us at covidtrackingquestions-us@joinzoe.com.

You can learn more about how the COVID & diet questionnaire feedback scores were calculated in this blog post.

No. The Diet Quality Score (DQS) and Gut Friendly Diet (GFD) score were created for general informational purposes only, based on your survey results. They are not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

We have rolled the COVID & diet feedback to a limited subset of app users in the US to test out functionality. We are exploring expanding the number of app users who receive results in the future.

On the 2nd September 2021, ZOE launched its wider health studies initiative in the ZOE COVID Study. For those who opted-in the data will be used to study a wider range of health conditions beyond COVID-19. 

The COVID-19 pandemic proved how critical our app-based data collection methods were in making new discoveries about disease. We’re now using the same methods and the help of our incredible contributors to fight all sorts of major diseases, including cancer, dementia, heart disease and more.