Boston – As the COVID-19 coronavirus pandemic grips the U.S., a healthcare science company, ZOE, announces a new free app that is helping to track the onset and progression of symptoms of millions across the nation. The app will help identify those at risk sooner and help slow the outbreak of the disease. Information about those who remain symptom-free will also support a better understanding of COVID-19. The research is being led by Andrew T. Chan, MD, MPH at Massachusetts General Hospital, in collaboration with the Harvard T.H. Chan School of Public Health, Professor Christopher Gardner at Stanford Medical, healthcare science company ZOE and Professor Tim Spector of King’s College London, U.K., where the app already has close to 2 million users providing critical information to researchers every day.

The COVID Symptom Tracker asks contributors to answer a few simple questions about themselves and their current health, then check-in every day to say whether they’re feeling fine or have noticed any new symptoms. Anyone can take part by downloading the free COVID Symptom Tracker app on iOS from the Apple App Store or Android from the Google Play store through

In response to recommendations by Stand Up To Cancer (SU2C), the app also includes questions for cancer patients and survivors, such as if they are living with cancer, what type of cancer, what treatment they are receiving, if they are in a clinical trial and where they are receiving treatment. The medical community knows that individuals with cancer and those receiving anti-cancer therapy are at increased risk for getting COVID-19. Research from China indicates that cancer survivors, as well as patients, are at increased risk for more serious illness. “There is too much we don’t know about COVID-19 in the cancer community,” stated Stand Up To Cancer CEO Sung Poblete, PhD, RN. “This data will be invaluable to assess how best to support this high-risk community and for cancer patients and survivors to contribute to combating this pandemic.”

The app is also being rolled out to participants in the Harvard-led Nurses’ Health Studies, which includes over 280,000 participants and is one of the largest and longest-running scientific studies in the world stretching back to 1976. Many participants in the Nurses’ Health Studies are active healthcare workers who are treating people with COVID-19 across the country and risking their own health to help Americans.

Right now, researchers and physicians still do not have an accurate picture of the symptoms of coronavirus infection, particularly if they are mild. While people are told to be alert for fever, persistent coughing and breathlessness, many are reporting symptoms such as headaches, muscle pains, loss of smell or taste, and diarrhea. But these can also be symptoms of less serious conditions like seasonal colds or allergies.

Without widespread testing for current or previous infections, this variation in symptoms makes it hard to track the true spread of the disease and figure out who might have already been infected. By gathering symptoms from millions of people across the country, researchers can build a better picture of the onset and progress of COVID-19, and start to figure out why some people become severely ill or die while others are only mildly affected. Also, by tracking the exposure of health care workers to their patients as well as their access to masks, gowns, and gloves, the data can be used to better understand how to protect those on the front lines of the fight against COVID-19.

Dr. Chan, a physician-epidemiologist at Massachusetts General Hospital, and Professor of Immunology and Infectious Diseases at Harvard T.H. Chan School of Public Health, said, “It is clear that symptoms of COVID-19 can vary widely, with some individuals harboring the virus with minimal symptoms or symptoms such as diarrhea that could be mistaken for something else. We know the reality is that there is a lack of available and timely testing of COVID-19,” said Chan. “This may be a better way to find out where hot spots of spread are, new symptoms to look out for, and use as a planning tool to target quarantines, send ventilators and medical equipment and provide real-time data to plan for future outbreaks. By also tracking in real-time the experience of health care workers, we can do a better job of understanding how to protect our first responders to this crisis.”

Secure anonymized data from the app will be made available to academic researchers, health services and policymakers on a strictly non-commercial basis. Crucially, the zip code-level data from the app should help hospitals and the CDC predict when and where the next wave of the virus will hit – vital information that will enable decision-makers to allocate limited resources more effectively and to get the country back on its feet as quickly as possible. The investigators are also making the app freely available to physicians and researchers around the country so that they can track the experiences of their patients and study participants. The ability to link this data to information that has already been collected in these populations will be invaluable to improving our understanding of risk factors for COVID-19 and outcomes from the disease.