Contact tracing with a technology twist
- By Stephanie Kanowitz
- Apr 30, 2020
When Virginia Gov. Ralph Northam announced a “blueprint” for reopening the commonwealth on April 24, he said contact tracing is a “key to moving forward.”
Northam isn’t alone in this belief. New York Gov. Andrew Cuomo and Mike Bloomberg launched a contact tracing program April 22 to build an online curriculum and training program for contact tracers with help from the Bloomberg School of Public Health at Johns Hopkins University and in coordination with New Jersey and Connecticut. Washington Gov. Jay Inslee announced April 21 his state’s plan to have 1,500 people conduct contact tracing -- recruited from the Department of Health, local health jurisdictions, members of the Washington National Guard and volunteer health care providers. Massachusetts Gov. Charlie Baker announced a program earlier in April that will tap public health college students to augment the contact tracing conducted by local boards of health.
Contact tracing, considered critical to slow the spread of the coronavirus, is a method by which public-health workers work with people who have an infectious disease to determine who they may have come in contact with while they were contagious. For a fast-moving virus such as COVID-19, it can help isolate only those people exposed, rather than everyone, as current shelter-in-place orders require.
What’s more, contact tracing can be effective, as efforts in Germany, Israel and South Korea have shown, but cash-strapped states are concerned about the number of trained tracers they might need. Additionally, questions about privacy protections, especially regarding medical information, have hindered use of the practice. Still, the benefits may outweigh the privacy risks during the pandemic.
That’s the tack the San Francisco’s Department of Public Health (SFDPH), the University of California at San Francisco and software company Dimagi have taken in partnering to create a web-based platform for contact tracing there. They’ve trained 140 people to use the system, citing a need to mobilize a larger workforce to be effective.
Contact tracers log in and see case ID numbers, names, ages, contact information and days since exposure. They can click on people assigned to them to get additional information such as recent notes about the case and details on whether they’re symptomatic.
When adding someone to the system, contact tracers ask people with confirmed positive COVID-19 tests about their occupation in case they need to follow up on workplace exposure, living situations to alert roommates or neighbors, and health provider information should they need to be referred for care. Contact tracers do not ask for financial information, Social Security numbers or citizenship status.
Then, they use a flow chart to refer people for testing or quarantine based on their response.
Currently, the information is not shared beyond SFDPH, said Mike Reid, a professor at the university’s School of Medicine, although sharing data could help. “I think it would be nice synergy if we were all using the same platform so that we could leverage data between counties,” he said during an April 16 media demonstration.
Other companies are developing technologies that anonymize contact tracing data, which could expand tracking. Apple and Google, for example, have just released tools that will help health agencies build apps for contract tracing using Bluetooth signals in mobile devices.
That’s how the CovidApp system works, too. Developed a few weeks ago by HypeLabs, a networking company, for use for free by government entities, the system has three parts. One is an app that conducts anonymous contact tracing in the background and alerts other app users if they have come in close contact with someone who tests positive for COVID-19.
Although health departments are asking COVID-positive patients about their contacts in the two weeks preceding their symptoms, people often don’t know everyone they pass in the grocery store, for instance, but the app will -- if those other shoppers also have the app, HypeLabs CEO and Co-Founder Carlos Lei said. “This is anonymous and private. No user information or personal information is ever required,” he said.
The app assigns a unique device ID -- a random number different from the telephone number -- and stores the unique device IDs of nearby devices that also run the app. Records of the encounters are stored in the device for up to 14 days before going to a central server run by the government entity using the system. What’s more, the app connects to devices even when they don’t have an internet connection.
The second part of the system is a health care web portal that aggregates the unique IDs from the smartphones. Medical workers can also upload results from people tested for COVID-19 and can adjust health statuses when there is a change. The data gives clinics and hospitals a way to estimate the number of people exposed so they can prepare.
The third part of the system is a government web portal that lets authorities distribute information to app users. Getting updates directly from the government “helps avoid the spread of misinformation,” Lei said.
To use it, government entities must implement the system on their servers and launch the application in app stores.
Not in use in the United States yet, CovidApp is being used by the Colombian government to reduce the spread of the coronavirus there, and Lei said 10 other governments are integrating the technology.
Some local governments are looking to a mobile app called Private Kit: Safe Paths developed by MIT. Available in app stores, it’s a location logger that uses GPS and Bluetooth to note the device’s location every five minutes for 28 days and provides time-stamped records of where users have been. Diagnosed patients can opt to share their location data with health officials. Using the Safe Places web app, those officials redact personally identifiable information from the location trail, and then Private Kit: Safe Paths notifies users who came in close contact with a diagnosed patient.
Another organization that shifted its efforts to COVID-19 contact tracing is the National Coalition of STD Directors, which has long tracked the spread of sexually transmitted diseases. In April, it pivoted a majority of its 1,600 STD disease intervention specialists to following the virus.
The coalition’s director expressed concern, however, about tracing efforts that aren’t administered by highly trained experts.
“Our country has done contact tracing for more than half a century for STDs and other infectious diseases before the COVID-19 pandemic using disease intervention specialists, frontline public health workers,” David Harvey, the coalition’s executive director said in an email to GCN. “We are fully supportive of digital contract tracing if it can be done in a way that respects people’s privacy and confidential health information. Right now there’s no guarantee that can happen.”
A report by Prevent Epidemics estimates that the United States would need 300,000 contact tracers to be effective, while the Johns Hopkins Center for Health Security and the Association of State and Territorial Health Officials say in another report that “our public health workforce needs to add approximately 100,000 (paid or volunteer) contact tracers.” They call for $3.6 billion in emergency funding from Congress.
Stephanie Kanowitz is a freelance writer based in northern Virginia.