The handshake came first. Then the high-five, fist bump and more recently, the elbow touch. Canadian researchers are now working on a new greeting, the CanShake.
It is not a mere salutation. The CanShake — which involves people shaking their phones at each other upon meeting to transmit contact information — is one of many emerging concepts seeking to use smartphones to do mass contact tracing to track and contain the spread of Covid-19. All involve harnessing common consumer technology to log people’s location or movements and match it against the location of people known to be sick.
There are dozens of versions, many already in practice around the world, including in South Korea, Singapore, China, Italy and Israel. But in the United States, privacy concerns and absence of national policy have made the approach slower to catch on.
Efforts are piecemeal. Google and Apple have a partnership underway to develop software for smartphones that would enable them to continuously log information from other devices. The MIT Media Lab has built contact tracing technology too. Three states — Alabama, North Dakota and South Dakota — have said they have deployed or are developing apps for tracking the virus.
The experimentation is happening as states, counties and cities are working to train people for the traditional, more arduous approach to contact tracing.
“There’s an army of contact tracers being hired. Technology can make this much more efficient,” said Dr. Gunther Eysenbach, editor of the Journal of Medical Internet Research, who is developing the CanShake.
George Rutherford, an epidemiologist at the University of California, San Francisco who is leading training of 10,000 California contact tracers, said digital ideas are bubbling up. “We’ve gotten several hundred people who want to show us their stuff,” he said.
But he said, they rely on smartphones, and some lower-income people most at risk from Covid-19 don’t have them.
The traditional method of contact tracing is time consuming and labor-intensive. It takes about 90 minutes for each case, Dr. Rutherford said — 60 minutes to interview the person who tests positive and 30 minutes to call or send texts to all the people the sick person remembers being in contact with.
Whatever the technology, there are trade-offs among the major ways that the information can be shared, stored and communicated: geolocation, Bluetooth and QR codes.
This software typically runs in the background on phones to help with location services like Google Maps. It can track people to within about 10 meters of their location, and be turned on and off voluntarily.
However, in other countries this technology has worked partly because it has been used automatically, with governments taking the data without asking permission.
After 3,000 people from the Diamond Princess cruise ship disembarked in Taiwan in late January — some of whom were later found to be infected — the Taiwanese government tapped into geolocation data of individual cellphone users to look for contacts between its citizens and the passengers.
The technology found 627,386 residents of Taiwan who had been in the vicinity of the passengers, whose own location data was also taken using other surveillance methods: the busses they took, the locations where they used credit cards, security-camera footage and their phone data.
Those residents all received text messages and were offered tests if they exhibited symptoms. Of 67 people tested, none were positive. Dr. Eysenbach, who is an author of a paper on the test, said it was effective but “did not require informed consent” and “would in the Western world be perceived as very privacy invasive.”
A report called “Apps Gone Rogue,” published in April by the MIT Media Lab, found that many international versions of contact-tracing technology “expand mass surveillance, limit individual freedoms and expose the most private details about individuals.”
That said, use of geolocation software doesn’t have to invade privacy, partly because it can be turned off by a user who knows he or she might be monitored. It also is possible to build applications that do not allow movement history to be accessed by outside sources, said Ramesh Raskar, an associate professor at the MIT Media Lab.
Bluetooth, the technology that your phone uses to communicate with other devices, can connect people to within one meter of one another and thus is more precise than geolocation technology. But it potentially creates privacy risk given that very precision.
The MIT Media lab has developed a contact-tracing concept that could use Bluetooth or geolocation technology in ways its developers say would not compromise individual liberties.
Safe Paths runs in the background of a person’s phone — with his or her permission — creating and storing a history of movements. If a person tested positive, that individual’s history would be downloaded to a database. After that, other people who used the service could run checks to see if their own movements had intersected with someone who tested positive — “completely private,” Mr. Raskar said, likening the idea to someone checking for rain without having to reveal his or her location.
The project is being developed with input from the Department of Health and Human Services, Harvard University and the Mayo Clinic. Mr. Raskar said several countries and 15 cities and states had expressed interest to MIT in the technology, but declined to identify them.
Apple and Google also use Bluetooth to let jurisdictions develop contact-tracing apps.
The companies’ technology offers privacy protections and is “a good-faith effort,” said Gaurav Laroia, a lawyer for Free Press, a nonprofit that is part of a consortium that includes the American Civil Liberties Union. The larger issue, though, he said, is whether people will choose to download these apps.
Bluetooth is also the technology behind the CanShake, an app in early development. When two people were near each other, they would shake their phones at each other to trigger a passing of their contact information through a Bluetooth connection. The data would be logged in each phone. Then, if either person got sick, the information could be downloaded by the authorities, who would — with the user’s permission — warn those in the contact log.
“The idea is to replace the handshake with the CanShake. It alludes to the idea that you ‘can shake’ again — not your hands but with your phone,” Mr. Eysenbac said.
When coronavirus cases surged in South Korea this winter, hospitals there asked people seeking tests or treatment to answer questions on their phones before arriving, including whether they had a fever or cough. After completing the responses, each person was sent a QR code to their phone.
When the person arrived at the hospital, a scanner captured the code and the individual’s information and the person was directed to get a Covid-19 test or not.
Initially, this was seen as a way to process people without paperwork, said Dr. Ki Mo-ran, a professor at the National Cancer Center Graduate School of Cancer Science and Policy.
Now, the country is considering expanding the use of QR codes. In May, Dr. Ki met with Prime Minister Chung Sye-kyun to recommend expansive use of the technology for contact tracing. In an interview, Dr. Ki said she described how it would scan visits by people to larger gatherings at restaurants, churches and night clubs, for example.
The proposed expansion of this technology was prompted, she said, by an outbreak that began in a nightclub. The government’s policy at the time was that visitors to such gatherings were required to sign in and leave their contact information.
But she said that 30 percent of the visitors to the nightclub could not be found because there was such a rush of people that not everyone gave information or partial data that could not be traced.
Under the new rules, she said, “people would generate a QR code, rather than writing down” their information. That code would be scanned when they entered and the information “would be connected to the government,” which, in the event of outbreak, could look for intersections between the sick and those nearby.
The government is exploring this idea of a “digital visitors list,” for a six-month test at nightclubs, restaurants and bars. The government would collect the data but would delete it after four weeks if it was not needed to trace an outbreak.
The report from MIT Media Lab noted that one source of abuse from all three technologies was that governments broadcast the location of people who were infected. Singapore published maps designating whereabouts of infected citizens while Korea sent text messages about their locations. It didn’t identify people by name, the report said, but it noted that divulging locations was still “making these places, and the businesses occupying them, susceptible to boycott, harassment, and other punitive measures.”
Dr. Ki acknowledged that privacy was a critical concern, but cautioned that protecting public health may be worth trade-offs. “Privacy is a very important issue,” she said, “but nowadays even though we try to protect personal privacy, it’s very critical to save the community, so we have to find the very appropriate balance.”