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Amid a tsunami of COVID-19 infections, strain on contact tracing grows. Should we keep trying?

People waited in line Wednesday to get a COVID-19 test at Anna M. Cole Community Center in Jamaica Plain.David L. Ryan/Globe Staff

Local health departments in Massachusetts, striving to track and prevent new COVID-19 infections amid an onslaught of new cases, are growing frustrated as testing turnaround times now stretch to a week in some cities and towns.

The delays have made it more difficult for tracers to quickly reach potential contacts of infected residents, and increase the chances those infected will spread the virus in the interim. At the same time, the staffing available to make contact tracing calls is wearing thin.

The strain is reflected in state data that show more than a third of newly infected residents are not reached within 24 hours of receiving their results by contact tracers to collect critical information about who else they might have infected. And, the data show, contact tracers have been unable to reach 25 percent of residents identified as potentially infected by another person.


The reports of significant delays in contact tracing and testing turnaround times follow criticism earlier in the pandemic of the multimillion-dollar state-led tracing initiative and have prompted some infectious disease experts to question the effectiveness and expense of contact tracing for COVID-19 in general.

Massachusetts is spending as much as $94 million this year on the effort. About $55 million is allocated to Boston-based Partners in Health to lead a tracing collaboration with local health departments, and $39 million to two other companies, Accenture and Salesforce, to establish and manage software for the collaborative.

In August, the state extended the Partners in Health contract through March, for an additional $22 million, with increased responsibilities including contact tracing at some colleges and boarding schools.

“It continues to boggle my mind why we continue to try to use this strategy that is just not working now,” Dr. Michael Mina, an assistant professor of epidemiology at the Harvard T. H. Chan School of Public Health, said in a recent call with reporters.


Contact tracing has long been used successfully to help contain outbreaks of other infectious diseases, including the 2014 Ebola outbreak in West Africa and the increasingly common clusters of measles across the United States. But there has been limited evidence of its widespread success amid a surge in COVID-19, a respiratory disease that spreads rapidly.

“Because we just keep focusing on pounding that and trying to say that is what’s going to work, it’s detracting from our ability to be creative and think of other solutions,” Mina said.

Mina has repeatedly called on federal regulators to approve over-the-counter, low-priced rapid antigen tests. The tests would allow consumers, without a doctor’s prescription, to test themselves at home and receive results in 15 minutes. Federal regulators have balked, saying the tests in development are not accurate enough.

Meanwhile, local health departments are stymied, because testing sites in Massachusetts rely on traditional molecular tests, processed at laboratories, that are taking longer and longer to produce results.

Health departments in Norwood, Needham, Canton, Westford, and Milton, to name a few, are reporting increasingly slower testing turnaround times.

“We are seeing huge delays of five to seven days,” said Sigalle Reiss, president of the Massachusetts Health Officers Association and Norwood’s health director.

While the state is reporting average turnaround times of just under two days, new data provided to the Globe show that 10 percent of tests in the past month have taken longer than three days and 5 percent longer than four days. That means thousands of tests are coming back each day after the time when a person is most infectious.


Dr. Louise Ivers, executive director of Massachusetts General Hospital’s Center for Global Health, said contact tracing is still an important tool to help tamp down infections. But she said its effectiveness is diminished without faster testing and significant investment in local health departments, including funds to increase and train staff and upgrade the software system they use to trace cases and communicate with Partners in Health.

Ivers, who has a team embedded in hard-hit Holyoke, was a long-time adviser to Partners in Health.

“Nine months into this pandemic, it would have been nice to see [state] investment in a shared information system that could help make this work,” she said.

Ivers is also worried about the 25 percent of contacts that tracers are not reaching. The state doesn’t release demographic data on those missed cases.

“We know inequity in Massachusetts has been a big part of the pandemic,” she said. “It is critical to know if the 25 percent they are not reaching are all communities of color. We need more granular data on who we are reaching by race and ethnicity.”

A recent paper by researchers in England and Harvard Business School concluded that a lapse in contact tracing may have exacerbated COVID infections and deaths in that country.


The researchers studied a glitch in which nearly 16,000 new cases were mistakenly not sent to tracers for up to a week in late September. They concluded that the glitch was associated with more than 125,000 additional infections and over 1,500 additional COVID-19 related deaths. Their work has not been peer-reviewed, and has not yet been published in a medical journal.

Public Health England, an agency in the country’s national health system, disputed the findings, saying its own analysis indicates the delay in contact tracing could not be definitively linked to increased illnesses and death. It said those increases coincided with students returning to universities, and other trends across England.

Dr. Shira Doron, hospital epidemiologist at Tufts Medical Center, read the UK paper and said it is logical to conclude that contact tracing would have prevented some of those cases.

“Every one of those traces does prevent potentially subsequent infections,” Doron said. “But contact tracing cannot stand alone. It’s only one measure that prevents some portion of the infections and it’s very, very imperfect.”

Doron also said tracing becomes much less effective amid a surge, when each infected person potentially has had contact with many other people and testing turnaround times lag.

She noted recent statements from Governor Charlie Baker that experts believe Massachusetts, based on the current volume of testing, is probably detecting just one in every four COVID-19 cases. But Baker said even that rate of testing may help prevent people from spreading the virus.


That sounds about right to Mike Armano, Lawrence’s health and inspectional services director. The city is in the midst of an onslaught, with about 100 new infections reported daily. He said they do the best they can with contact tracing, despite bottlenecks in testing and with residents, many of them immigrants wary of legal repercussions, hesitant to share information.

“Sometimes in the prevention world you are not sure what difference you are making, but you have to have hope,” Armano said. “If it’s one case we stop . . . then we made a difference.”

Kay Lazar can be reached at Follow her @GlobeKayLazar.