Baker’s ‘test and trace’ gambit
Will contact tracing help get the state up and running?
GOV. CHARLIE BAKER, a data and systems guy from way back, has placed a big bet that a methodical approach to the coronavirus pandemic is what it will take to limit the virus’s spread and get the state up and running again. Specifically, he has hitched his wagon to a system known in public health circles as “test and trace.”
In this case, it means testing lots of people for the novel coronavirus and isolating those who are infected, while deploying an army of 1,000 interviewers to find out who those people had recent contact with and then reaching out to encourage those contacts to quarantine for 14 days to help break the chain of transmission of the contagion.
In announcing the effort on April 3, Baker said the state was “breaking new ground in the fight against COVID-19,” boasting that Massachusetts was the first state to launch such a system.
But will the approach work?
The Massachusetts effort, being carried out in collaboration with the Boston-based global nonprofit Partners in Health, was spurred largely by the successful test and trace approach used in South Korea, Singapore, and Taiwan. But those countries’ approaches are highlighted by enormous government intrusion to quickly access information, an invasion of privacy that seems unlikely to be tolerated here.
The report says a huge increase in testing is needed for the Massachusetts approach to be effective. The state would need to roughly double its testing from the current level of 5,000 to 8,000 tests per day to 10,500 to 17,000, according to the Tufts analysis. The need to ramp up testing is made clear, the report says, by the high rate of positive findings in US testing — about 20 percent nationally, with an even higher rate of 25 percent in Massachusetts. Those figures suggest testing has been too narrowly focused on only those showing possible COVID-19 symptoms.
In addition to a lot more testing, the report says it will be crucial that the state effort quickly determine an infected person’s recent contacts and then reach those people to let them know they’ve been exposed to the virus. “The fact that asymptomatic people can spread Covid-19 complicates the work of contact tracing — and puts a premium on speed,” says the report. The efforts in Asian countries largely relied on “digital footprints” from cellphones through which massive amounts of data about the movement of people can be quickly harnessed. But that ‘“raises serious concerns about privacy and surveillance,” the report says.
The Massachusetts effort is relying instead on one-on-one phone interviews to obtain that information. The state initiative was the subject of a lengthy story in the New York Times last week. In it, Partners in Health cofounder Paul Farmer, a physician acclaimed for his public health work in developing countries, said the human contact from interviewers is invaluable in helping form a bond of trust with frightened patients.
But it can also slow the process down compared with the Asian models that have relied on technology to map contacts. A Brigham and Women’s Hospital physician who worked on the Ebola crisis in Africa told the Times that the interview-based approach means you have to “manually figure out where someone went,” giving more time for virus transmission among unsuspecting contacts.
The Asian experience also shows that even the best conceived plans can fail when there are holes in them.After a highly successful first-wave effort put a lid on the virus by using contact tracing and making testing widely available, Singapore was jolted by a sudden doubling of cases in recent days, a surge centered in dormitories housing migrant laborers. The experience of the prosperous Southeast Asian city-state now stands as a harrowing cautionary tale for the US and other countries.