Contact Tracing: There’s an App for that

By June 2, 2020 No Comments

By Jody DiPerna
Pittsburgh Current Lit Writer


Because of the coronavirus pandemic, ‘contact tracing’ is a term that has moved out of the hidden halls of public health and medical research and into the common lexicon. One of the most essential tools health workers have to track and contain infectious diseases, contact tracing has been used to fight diseases like polio, measles and HIV.  

Dr. Catherine Haggerty, Associate Professor in the Department of Epidemiology at the University of Pittsburgh’s Graduate School of Public Health explained it in clear terms. 

“Through an initial case investigation, public health workers interview a patient to help them recall all of their close contacts during the timeframe that they have been infectious. As a next step, each of these close contacts are notified of their potential exposure and given instructions …” she told the Current via email. 

The idea of an infection network has been around for a long time, but new technology may be able to lend a hand as the nation opens up, ready or not. While behemoth companies like Google and Apple work on their own apps, a group at Carnegie Mellon has designed and launched NOVID, a contact tracing app they think is more effective and nuanced, and is also private. 

If two people have NOVID loaded on their phones and are in contact with one another for a significant period of time (15 minutes or longer), the technology records and stores that information. If one of those people then tests positive for coronavirus, they would self-report it and the app would notify the other person that they had contact with a positive case of COVID-19 and may be contagious themselves.  

Po-Shen Lo, a math professor at CMU, who also coaches the USA International Mathematical Olympiad Team, leads the NOVID team. Right around the time Pennsylvania was shutting down in mid-March, Lo says he desperately wanted to help, but felt like ‘a useless mathematician.’ Then he started to imagine the virus as a network theory problem — a light went on. 

“I thought, if we shut down totally for a year, we all starve. We need to have some way of helping to control the spread of COVID-19, where every single person plays a part, instead of us waiting for Big Brother or Mother Government,” Lo told the Current via telephone. 

“With an anonymous network, you could actually curtail the spread of COVID-19. If you saw a hotspot in the network, you could send a message saying, be careful, something’s coming. You might be able to help save lives.”

Lo quickly assembled a team of some of the very best tech designers, architects and engineers and they hit the gas hard. NOVID doesn’t require any user information, like name or email or phone number. That anonymity was vital to the team. 

“We don’t know who they are, we don’t know where they are, we don’t know anything about this person. We see User 82 and we can see that they have connections to User 103 or User 56,” explained Macy Hyland, part of the outreach team for NOVID. 

Continuing that example, if User 82 tested positive, they would self-report. Then NOVID would alert Users 103 and 56 with a notification along the lines of, ‘Someone just self-reported a positive test. During the time that they were potentially contagious, you were with them and may have been infected.’ 

NOVID user phones talk to each other through bluetooth, rather than GPS information. When you flick on bluetooth to use headphones or a speaker, your phone scans for devices that are nearby. NOVID works just like that — if two NOVID users are together, the devices will clock one another and make note of it. 

But false positives can happen because bluetooth often picks up devices that are in another room or on a different floor. So the NOVID crew added an ultrasound component. One phone asks the other, make a noise for me. It’s a sound that humans can’t hear, but the tech can. This sound won’t be detected through walls and floors, thus NOVID avoids false positives that could occur, especially in apartment buildings and dorms.

“We put it together as self-reporting, so that people could start to be alerted,” Lo said. Self-reporting is kind of a high tech honor code, which works if users honestly report positive tests and self-quarantine as appropriate. 

The tech can only do so much. At the end of the day, humans are going to human. 

According to Dr. Haggerty, the value of old-school contact tracers is that they are a two way street of information, both gathering data and also providing valuable instruction and intelligence in the community. 

“A key strength of active case investigation and contact tracing is that instructions on isolation and care of cases and quarantine of close contacts can be immediately shared and explained. Additionally, active identification and continued monitoring of close contacts provides public health officials an ability to quickly identify if symptoms develop among close contacts so that testing and isolation can be rapidly implemented if needed,” Haggerty said. 

One of the challenges unique to coronavirus is that scientists estimate that almost half of the transmissions happen before you have any symptoms at all. If you have the common flu, most of the transmission happens after you start to feel bad. A responsible person will avoid elderly or immunocompromised friends and relatives; they might stay home from work. COVID-19 doesn’t allow for individuals to make those conscientious decisions because you can be contagious for two weeks without knowing it. 

Simply put, NOVID is trying to give you that sensory information before you feel sick. 

Lo says that with every new user, NOVID works better, creating a safer environment, but he noted that this is just the first step and they are hoping to partner with health care providers and public health authorities.

“It’s very rare that you can say that the problem we’re working on is one of the most important problems in the entire world at the moment. We started this because I wanted to stop the spread of COVID-19.” 

Leave a Reply

Pin It on Pinterest