In August 2020, Virginia became the first state in the nation to launch an app to track individual exposure to COVID-19. Since then, over 28 states have followed suit.
With the rollout of MassNotify on Tuesday, Massachusetts became the 29th. In his announcement, Governor Charlie Baker touted the state’s high vaccination rate and pitched the service as a way to “embrace our new normal.”
But the app’s launch at a time when COVID-19 cases have declined dramatically and life is edging back to normal has some experts scratching their heads.
Ramesh Raskar — a professor at the Massachusetts Institute of Technology and founder of the PathCheck Foundation, a nonprofit that helps develop digital contact-tracing apps — said MassNotify has come online “definitely too late.”
“I think everybody is disappointed that it took so long,” Raskar said. He believes both lives and hospitalizations could have been saved if it were rolled out sooner. By one count, every 200 downloads of an exposure-notification app has the potential to save a life, he said.
“This was a no-brainer to launch an app that other states had already launched,” Raskar added. PathCheck has worked with other states — including Alabama, Hawaii, Louisiana and Minnesota — to launch their apps. It offered its services to Massachusetts but was not chosen, Raskar said.
“We may have saved hundreds of lives and many hospitalizations if the app was launched during the winter spike before vaccines were available,” he added.
Kate Reilly, spokeswoman for the state’s COVID-19 Command Center, said that Massachusetts spent several months studying the technology, including multiple pilot programs, to ensure its efficiency and safety. It has now proven to be “safe, effective, and secure,” she said.
MassNotify, a free service developed in conjunction with Apple and Google, works anonymously and “does not track” users or divulge their information, the state said Tuesday in its announcement.
Whenever individuals who have opted in to the service are near each other, their phones exchange random codes via Bluetooth. If an individual tests positive for COVID-19, they’ll receive a text with instructions on how to anonymously share their result. That will notify the other individuals whose phones were recently near theirs of possible exposure to COVID-19.
The more who opt in, the better the service works.
In the first two days after MassNotify’s launch, almost 500,000 residents signed on to use it Reilly said. That’s about 7 percent of the state’s population.
Elsewhere in the United States, uptake levels of contact-tracing apps have been “incredibly low,” said Sarah Kreps, director of the Cornell Tech Policy Lab, which studies the politics of emerging technologies. She called the launch of MassNotify at this stage in the pandemic “somewhat baffling.”
“It seems to show a lack of understanding about public behavior with respect to these apps, which is that people are more likely to use them if they think that this pandemic is still going on,” Kreps said.
A study she co-authored in December found that just 42 percent of respondents supported the use of such apps. That was lower than for other surveillance measures, such as enforced temperature checks, which had 62 percent support, and centralized quarantine, which had 49 percent support.
The actual use of exposure-tracking apps has been even lower.
Alabama, for example, saw just 150,000 downloads of its app from August to November, equal to about 3 percent of its population. And just 380 residents had any entered diagnostic data in the app.
Kreps attributes the dearth of downloads to concerns about privacy, which her study found was “the single most important feature” to users. “What they were worried about, with something as sensitive as medical information, was that their data be secure,” she said.
In November, Baker addressed concerns about privacy as the state was beginning work on the app.
“Part of the reason you haven’t seen digital contact tracing adopted in a big way . . . is the concern about basically targeting and tagging people based on the presence of their phone,” Baker said. “The privacy issues associated with this . . . are ones that we don’t believe have been adequately addressed by any of the platforms that we’ve talked to.”
It’s unclear what changed to pave the way for MassNotify. The technology made by Apple and Google was already in use in other states, and worked roughly the same way then as it does now.
Jeffrey Kahn, director of the Johns Hopkins Berman Institute of Bioethics, said exposure-notification apps could still benefit individuals who are vaccinated, like himself. He opted in to a version of the app in Maryland earlier in the pandemic but said it wasn’t useful to him because he was confined to his house. Since his vaccination, though, Kahn said he has been out and about.
“In some sense, it’s now much more important for me to know if by going someplace I might have been exposed if that alert comes to me, so in some sense it’s more important now than it was before,” Kahn said.
Dr. Philip Landrigan, director of the Global Public Health Program at Boston College, said the consensus is that exposure-notification apps are only somewhat beneficial to public health.
“They make some difference around the edges,” Landrigan said. “It’s not going to make a huge difference, but it’s one of these situations where every little bit helps.”
Landrigan said it would have been preferable if Massachusetts had implemented the app sooner, but that it probably would not have had a significant effect.
Ryan Calo, codirector of the University of Washington’s Tech Policy Lab, said Massachusetts should continue to focus its efforts on vaccinations, not exposure notification.
“Vaccinated people don’t generally contract or spread COVID, making an app superfluous,” he said. “Meanwhile, it seems implausible that people who won’t get vaccinated will somehow use an app provided by the government, let alone upload their health status to it.”
“Worse still, some people may decide that the app furnishes a substitute for vaccination to keep them safe — which would be deeply misguided,” he added.
Camille Caldera was a Globe intern in 2022.Follow her on Twitter @camille_caldera.