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Can Smart Phone Apps Help Beat Pandemics?

Posted on by Dr. Francis Collins

Crowd of people with connection symbols.

In recent weeks, most of us have spent a lot of time learning about coronavirus disease 2019 (COVID-19) and thinking about what’s needed to defeat this and future pandemic threats. When the time comes for people to come out of their home seclusion, how will we avoid a second wave of infections? One thing that’s crucial is developing better ways to trace the recent contacts of individuals who’ve tested positive for the disease-causing agent—in this case, a highly infectious novel coronavirus.

Traditional contact tracing involves a team of public health workers who talk to people via the phone or in face-to-face meetings. This time-consuming, methodical process is usually measured in days, and can even stretch to weeks in complex situations with multiple contacts. But researchers are now proposing to take advantage of digital technology to try to get contact tracing done much faster, perhaps in just a few hours.

Most smart phones are equipped with wireless Bluetooth technology that creates a log of all opt-in mobile apps operating nearby—including opt-in apps on the phones of nearby people. This has prompted a number of research teams to explore the idea of creating an app to notify individuals of exposure risk. Specifically, if a smart phone user tests positive today for COVID-19, everyone on their recent Bluetooth log would be alerted anonymously and advised to shelter at home. In fact, in a recent paper in the journal Science, a British research group has gone so far to suggest that such digital tracing may be valuable in the months ahead to improve our chances of keeping COVID-19 under control [1].

The British team, led by Luca Ferretti, Christophe Fraser, and David Bonsall, Oxford University, started their analyses using previously published data on COVID-19 outbreaks in China, Singapore, and aboard the Diamond Princess cruise ship. With a focus on prevention, the researchers compared the different routes of transmission, including from people with and without symptoms of the infection.

Based on that data, they concluded that traditional contact tracing was too slow to keep pace with the rapidly spreading COVID-19 outbreaks. During the three outbreaks studied, people infected with the novel coronavirus had a median incubation period of about five days before they showed any symptoms of COVID-19. Researchers estimated that anywhere from one-third to one-half of all transmissions came from asymptomatic people during this incubation period. Moreover, assuming that symptoms ultimately arose and an infected person was then tested and received a COVID-19 diagnosis, public health workers would need at least several more days to perform the contact tracing by traditional means. By then, they would have little chance of getting ahead of the outbreak by isolating the infected person’s contacts to slow its rate of transmission.

When they examined the situation in China, the researchers found that available data show a correlation between the roll-out of smart phone contact-tracing apps and the emergence of what appears to be sustained suppression of COVID-19 infection. Their analyses showed that the same held true in South Korea, where data collected through a smart phone app was used to recommend quarantine.

Despite its potential benefits in controlling or even averting pandemics, the British researchers acknowledged that digital tracing poses some major ethical, legal, and social issues. In China, people were required to install the digital tracing app on their phones if they wanted to venture outside their immediate neighborhoods. The app also displayed a color-coded warning system to enforce or relax restrictions on a person’s movements around a city or province. The Chinese app also relayed to a central database the information that it had gathered on phone users’ movements and COVID-19 status, raising serious concerns about data security and privacy of personal information.

In their new paper, the Oxford team, which included a bioethicist, makes the case for increased social dialogue about how best to employ digital tracing in ways the benefit human health. This is a far-reaching discussion with implications far beyond times of pandemic. Although the team analyzed digital tracing data for COVID-19, the algorithms that drive these apps could be adapted to track the spread of other common infectious diseases, such as seasonal influenza.

The study’s authors also raised another vital point. Even the most-sophisticated digital tracing app won’t be of much help if smart phone users don’t download it. Without widespread installation, the apps are unable to gather enough data to enable effective digital tracing. Indeed, the researchers estimate that about 60 percent of new COVID-19 cases in a community would need to be detected–and roughly the same percentage of contacts traced—to squelch the spread of the deadly virus.

Such numbers have app designers working hard to discover the right balance between protecting public health and ensuring personal rights. That includes NIH grantee Trevor Bedford, Fred Hutchinson Cancer Research Center, Seattle. He and his colleagues just launched NextTrace, a project that aims to build an opt-in app community for “digital participatory contact tracing” of COVID-19. Here at NIH, we have a team that is actively exploring the kind of technology that could achieve the benefits without unduly compromising personal privacy.

Bedford emphasizes that he and his colleagues aren’t trying to duplicate efforts already underway. Rather, they want to collaborate with others help to build a scientifically and ethically sound foundation for digital tracing aimed at improving the health of all humankind.


[1] Quantifying SARS-CoV-2 transmission suggests epidemic control with digital contact tracing. Ferretti L, Wymant C, Kendall M, Zhao L, Nurtay A, Abeler-Dörner L, Parker M, Bonsall D, Fraser C. Science. 2020 Mar 31. [Epub ahead of print]


Coronavirus (COVID-19) (NIH)

COVID-19, MERS & SARS (National Institute of Allergy and Infectious Diseases/NIH)

NextTrace (Fred Hutchinson Cancer Research Center, Seattle)

Bedford Lab (Fred Hutchinson Cancer Research Center)

NIH Support: National Institute of General Medical Sciences


  • susan ransome says:

    thank you, Dr. Collins
    yes: in short run, we should use all our options in this crisis, Temporarily.

    using physical barriers: infirmaries and quarantine centers will be even better to effectively slow/ halt transmission

    I’d appreciate knowing why we don’t consider those options used very effectively in Asia

  • P. says:

    Thank for your post sharing with us. Really it’s a very helpful post. Hope everybody will be benefited from your post.

  • DR. SAUMYA PANDEY, PH.D. says:

    An innovative amalgamation of healthcare and smartphone-based information technology in the Covid-19 pandemic!
    Future critical insights are warranted to prove beneficial in cost-effectively managing and preventing Covid-19 and associated pandemics.

  • Mark Andrew says:

    As we don’t know how tough the pandemic will be on us, we need to know everything about it for the safety of ourselves and our loved ones …

  • Taoheed H. says:

    Thanks for sharing this kind of article, it’s really helpful.

  • Waqas Majeed says:

    Spot on information, you really nailed it. In fact you highlighted some very interesting aspects of digital data. All of your observations clearly makes sense.
    I will actually like to tweet your post link as I really liked this information you shared.

  • Rhonda Bompensa Zimmerman says:

    There are issues with this type of application intended to help protect our health as it may make us vulnerable, in terms of personal privacy protections and civil liberties. However, I would hope that collaborative measures might prevail with a workable solutions in the long-term. Looking forward to staying informed about data surrounding these types of health/smartphone technology apps. It will take time to address people’s warranted concerns before we even begin to consider using them (in my opinion).

  • Bridget says:

    I have serious concerns about the slippery slope of eroding privacy and civil liberties for these “apps”- this seems eerie of Communist China and yet this is America, founded on freedom. All of us are where we are today because of that freedom and future generations deserve to have that maintained. We are already being tracked now without just cause on cell phones. I would personally never want to commit to this on that grounds and am appalled tracking is happening already. Can we put this into perspective please that the case fatality rate for COVID is around 1%, given the data. More akin to seasonal flu. That is not just cause to begin such extremely intrusive measures. Risk of contact with someone does not equate to it actually occurring/ that person getting sick, and forcing someone to quarantine which this could then be used to do. I feel there are too many risks if information gets in the wrong hands as well. It could fuel a great deal of anxiety in those already battling that already. What parameters would be used for how close you are to someone? Would it be used year round, enforced by law enforcement, etc. Self Quarantining when actually sick has been used just fine for a long time. Maintain the Constitution please.

  • thedan1337 says:

    Just wear a mask, folks. It’s not that hard to do. Don’t participate in protests either, it’s a mass gathering …

  • worldentire says:

    Hey, thanks for your information and informative blog post . . .

  • U.R. says:

    Very informative blog. Recently I bought a smartphone and I think it’s really comfortable and worth buying.

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