When will the US contact-tracing app be ready?

As the UK launches its new NHS Test and Trace app for COVID-19, the US is yet to get to grips with this vital part of handling exposure to the novel coronavirus

After a false start, the UK government today begins rolling out its COVID-19 contact-tracing app. The app uses the Exposure Notification System (ENS) provided by Google and Apple for use by public health officials in the global fight against the coronavirus. And while many other countries around the world have launched contact-tracing apps, the US initiative remains disjointed.

According to a statement from David Burke, Vice President of Engineering at Google at the end of July, “public health authorities have used ENS to launch in 16 countries and regions across Africa, Asia, Europe, North America and South America, with more apps currently under development.” But in the US, although 20 states are considering it, the ENS API is yet to be deployed in any app.

Although ENS capabilities have been live for three months, why is it that the United States lags so far behind in its utilisation? If other countries have been able to manage contact tracing capabilities using similar technology, what is precluding the United States from making these apps available?

The UK, like the US, has struggled with the development of its contact-tracing app. At first it seemed like the UK had stolen a lead. NHSX, the technology arm of the NHS, started development of a Bluetooth-enabled app in March before the Google/Apple partnership was even announced. But a trial of the app on the Isle of Wight revealed serious problems with registering the presence of iPhones. So the decision was taken in June to abandon these efforts and instead to build an app using the Google/Apple ENS, which only became available in mid May. The app also has a QR code scanner to log visits to venues like pubs and cinemas.

Meanwhile, other parts of the UK – Scotland and Northern Ireland – diverged from England and Wales, and decided to adapt an app developed for Ireland, which launched on 7 July. Northern Ireland launched its contact-tracing app on 30 July. The apps, developed by Nearform in Waterford, Ireland, are built on the Google/Apple ENS, and work across the border between the two countries – a world first. Nearform is now in discussions to develop an app for the State of Pennsylvania.

How does ENS work?

A person may download an ENS enabled app. The app will assign a random ID for the device. To ensure user privacy, IDs are randomly assigned and cannot be traced to a specific individual or location. When two people come into close proximity, their phones use Bluetooth to exchange random IDs assigned by the app. If one of them contracts COVID-19, she or he updates her/his status in the app.

In a decentralised app using the ENS API, the app then provides the anonymised ID to a central database. The app periodically checks the database for a list of IDs and looks for matches with IDs on the phone. If an ID you have come in contact with has been confirmed as having tested positive for COVID-19, you’re immediately notified and given instructions from public health officials . 

How does an app assist contact tracing efforts?

In an interview with the New York Times, George Rutherford, an epidemiologist at the University of California, explained just how time-consuming and labour-intensive the traditional contact-tracing process can be. According to Rutherford, it typically takes at least 90 minutes to assess just one positive case, 60 minutes to interview the person who tested positive and then a minimum 30-minute process to map and call all those the person remembers coming in contact with. Not only is this process tedious, but it also does not accurately trace everyone a person may have come in contact with. Will a person interviewed remember the stranger who they shared a park bench with? And even if they do, how can this bench companion be tracked down and informed?

To aid in tracking efforts, the United States has employed an additional 37,000 people as contact tracers, bringing the national total to just over 68,000, but this is still not enough to meet current needs. An NPR survey conducted in June found that only seven states and Washington DC were adequately staffed with enough contact tracers. Johns Hopkins researchers found that to meet current needs, the US will need to add at least another 100,000 contact tracers to the public health workforce. 

Contact tracers’ efficacy is limited simply by the fact that people forget who they may have interacted with. In states where lockdown restrictions have been eased, someone who tested positive for the virus could have come in contact with many more people (i.e. strangers in a restaurant) than is within the purview of their memory. Assuming that tracers are able to reach at least 10 contacts per case (a best-case scenario), it’s estimated that these efforts will only be able to reach about 45% of people who a positive case may have come in contact with.

Contact tracing apps have the ability to remove human fallibility out of the process by accurately and automatedly documenting each interaction be it with a friend or a stranger, and informing relevant parties of exposure in a faster way than what was conventionally possible. Rather than replacing human efforts, an app helps to enhance them. 

Contact tracing apps have already seen considerable success in countries like Taiwan, South Korea, China, and India. The one thing in common with these countries’ successful apps? A singular, centralised app and location tracking system launched by the government. 

Decentralised versus Centralised – what works?

The countries who have seen considerable success in digital contact tracing efforts include governments of South Korea and Taiwan, where governments have more access to personal data.

In South Korea, a mandatory government app was to be downloaded by all visitors coming into the country. The app would record their location using GPS and ask for a regular temperature check to be recorded. 

All visitors, whether they presented with symptoms or not, were required by law to isolate for 2 weeks, with the app tracking their daily updates. Additionally, those found violating isolation mandates, were asked to wear a location-tracking bracelet to preclude a repeat infraction. 

Further, South Korea collated this data to create a national database to track COVID-19 transmission. Health authorities have access to CCTV footage, credit card transaction data, travel and location history to accurately map patients whereabouts. Using this data bank, it would take officials only 10 minutes to map out everywhere a patient has been. 

With these tracing efforts, the South Korean government has been able to effectively manage the spread of COVID-19 in a country that’s five times more densely populated than the US. However, this centralised approach, which gives the government exceptional, mandated access to personal location data, has been questioned by some civil liberties groups, making it difficult to replicate this approach in the United States or the European Union. 

ENS provides a decentralised approach to assist in these efforts. In a centralised approach, a user’s phone provides ID information plus codes gathered from other phones to a centralised cloud. A computer server then uses the centralised cloud database to match contacts and send alerts (meaning all data is stored through one central authority and then disseminated). A decentralised app assures that an individual phone is the only one whose data is logged, meaning there is no central collation of IDs and user logs.

What’s different about the United States?

In the United States, there has been a raging debate regarding the role of the federal government in contact tracing and COVID management efforts. The policies put in place so far by the Trump administration and the Centers for Disease Control (CDC) have delineated increasing power and funds to states and state legislatures to develop their own contact tracing methods and ground staff in a manner that’s appropriate to their locale and needs. 

This federal versus state approach taken at face value may seem like the smart decision for a better allocation of resources, the absence of a centralised app and data collection system will undoubtedly result in varied reporting and has the potential to lead to flawed management techniques. 

Some states already have their own contact tracing apps. Tim Brookins, the developer of Care19, a tracing app being used in North and South Dakota, is set to incorporate ENS API in a future release. Brookins and the Care19 team have found that while positive cases are being tabulated through the app, due to the voluntary nature of the download, less than a third of all eligible Dakotans are actually using the app, which currently operates using location data. With ENS capabilities embedded in the future roll-out of the app, privacy concerns regarding user location and identity are meant to be alleviated. Will this result in higher downloads and user interactions?

Digital privacy remains a major concern for Americans. A study conducted in April by The Washington Post and the University of Maryland found that 56% of Americans interviewed said they would not trust big tech companies like Apple or Google to keep their COVID diagnosis anonymous. Even though the ENS API makes it so that all user interactions are kept anonymous and untraceable, Google knows it will still have to make leaps and bounds when it comes to assuaging public scepticism.  

Countries such as Poland, Switzerland, Ireland, Germany, Italy and Latvia have all utilised ENS API for their contact tracing efforts, made possible by the fact that their respective nationalised healthcare services have developed the app and advocated for its use. The CDC at this time has not made any similar efforts in the United States.

For the meantime, this will mean independent ENS enabled contact tracing apps will have to be created by independent companies and developers in the United States who are motivated either by an altruistic mission or with the vision to have their apps purchased by state governments. As of mid-June, there were only three states: Alabama, South Carolina, and North Dakota with plans to embed the Google Apple ENS within their contact tracing apps.

Sharing data across borders

Through the decentralised policy approach, the transferability of data across state borders poses a sizable challenge. As travel restrictions across the US are eased, there is an increase in incoming and outbound traffic between states. 

Imagine a person goes back and forth from his beach house in New Jersey on the weekends to his home in New York during the week, a commonplace occurrence. If this person tests positive in New York and it’s logged in the respective app for the state, there are currently no capabilities set in place for the automated transfer of his positive status information to those he may have been in contact with at the beach in New Jersey. For this, he would have to download a separate New Jersey state app and log his positive case in manually for a second time, which, when voluntary in nature, is a difficult task to hold people accountable to. 

This inability to centrally log movement between states and defining parameters for exposure can pave the way for uneven reporting metrics.

The best solution would be to create one nationwide app that will utilise ENS no matter where a user is in the country. Since such an app isn’t an available option at this time, the US could look to the EU’s approach to contact tracing.

Most EU states have launched their own mobile apps as part of their test and trace efforts. The majority of them are decentralised, so data remains on users’ phones rather than being stored in a central database. As Europe’s borders began to open up, European Union member states agreed in June to a set of technical specifications to enable the safe exchange of data between national contact tracing apps. The common approach supports the relaxation of containment measures across the EU. The new technical specs will enable apps to be interoperable so users only need to install their country’s app.

Who gets left behind?

It’s critical to note that a substantial number of people are immediately out of the running to participate – namely those without smartphones.

According to the Pew Research Center, in 2019, 96% of all Americans owned a mobile phone, with about 80% of mobile phone owners owning smartphones. However, for Black and Hispanic Americans as well as senior citizens and low-income residents (all within the highest risk groups for COVID-19), had the highest percentages of no smartphone ownership, with nearly 40% of senior citizens reporting not having a smartphone. So the desired effects from an ENS app would perhaps not be able to reach within the communities where contact tracing is so crucially required, especially for individuals who overlap in risk-categories (i.e. a low-income Black or Hispanic senior citizen living in a city alone with no smartphone).

Final Verdict

Utilising ENS in apps as a means to contact-trace could provide some semblance of order, privacy, and automation to a process that is still being conducted primarily in an inefficient brick-and-mortar way. Allowing for a greater amount of reporting will aid researchers and health officials to take the first step in creating more robust health responses within their locales, but it’s clear that an app alone will not solve the country’s current contact tracing problems.

Additional reporting from Alex Guest