'It's Just Impossible': Tracing Contacts Takes Backseat As Virus Spreads

Faced with more than 70 cases of the novel coronavirus and a deadly outbreak in an assisted living community in his town, Ed Briggs is overwhelmed.

The health director for Ridgefield, CT, says there is no way that he and his staff of two can identify and isolate all the people who have interacted with an infected patient, not at the rate cases are multiplying across the town.

"Tracing exposures of exposures of exposures. It's just impossible," Briggs said. "The cases are to the point where we can't possibly trace everybody back now."

Known as contact tracing, this vital but labor-intensive process is becoming increasingly difficult for stretched health departments in towns and cities across the United States, which has more than 160,000 cases, more than any country in the world.

A massive testing campaign, coupled with intensive contact tracing, is credited with helping South Korea slow the spread of coronavirus, whereas the United States has been criticized for a slow response.

Epidemiologists say such investigations can mean the difference between nipping an outbreak early and effectively losing control, as has happened in hot spots where contact tracing has given way to lockdowns as the primary tool to prevent spread.

Some states outside of the major population centers have taken that advice to heart, as the virus continues its march across the United States. Health officials in those areas acknowledge, however, that it is a race against the clock and that they, too, will be unable to carry out such widespread tracing if the case numbers climb beyond a certain point.

Wyoming, for one, has five staff in its state's infectious diseases unit working to identify all contacts with a person who has tested positive, and then asking or ordering them to self-quarantine, and monitoring their health.

"Our numbers are small enough," said Kim Deti, a spokeswoman for Wyoming's health department, which has reported 109 cases so far and no deaths. "We'll maintain it as long as we can."

West Virginia is tapping its national guard to assist in a similar effort at expansive contact tracing, and coupling that with a stay-at-home order and other distancing steps. On Sunday, the state reported 145 cases and its first coronavirus death.

"It's incredibly important that at the same time as you are doing that rapid contact investigation and tracing and outbreak management, that we do the preventive measures in partnership with that everywhere," state health officer Cathy Slemp said at a news conference last week.

Alabama, which has confirmed nearly 1,000 cases, is attempting to investigate contacts for all of them, a spokeswoman for its health department said, noting that contact tracing has been an "effective tool in reducing the spread" for tuberculosis and other communicable diseases in the state.

Identify and contain

New York City, which accounts for a quarter of all cases nationwide, is an example of how the lack of testing in January and February handicapped so-called "disease detectives" from identifying initial infections and containing the spread.

The city is now limiting its detectives to contact tracing for outbreaks involving health care workers and clusters in assisted living facilities and nursing homes, its health commissioner, Oxiris Barbot, said during a news conference earlier this month.

Louisiana, an emerging hot spot with 5,237 cases and 239 deaths, has similarly narrowed its contact tracing in the New Orleans area, the epicenter of the state's outbreak, to focus on vulnerable populations and high-risk groups.

Theresa Sokol, an assistant state epidemiologist in Louisiana, said that by the time the initial patients in the New Orleans area were identified the virus had already taken hold in the community. As cases mounted, she said, social distancing became a more effective tool than contact tracing.

But outside New Orleans there is reason to believe that digging deeply into all cases can yield results, especially when combined with the governor's statewide stay-at-home order, Sokol said: "I believe that there is still time."

Like other municipalities in the New York area, Ridgefield closed its schools and non-essential businesses. But the virus has continued to spread broadly beyond the cluster at the Benchmark Senior Living at Ridgefield Crossings facility, which has been linked to six of the town's seven deaths. The town hired an additional employee to process the deluge of coronavirus-related data, but keeping up is a challenge.

"It's overwhelming for a small health department," First Selectman Rudy Marconi said.

Looking ahead, experts see aggressive testing and contact tracing as key to handling subsequent waves of the virus.

Kenneth Castro, a professor of global health, epidemiology, and infectious diseases at Emory University, said local, state, and federal governments should start recruiting an "army" of people to handle contact investigations.

"Identify and contain is better than having society shutdown. It's a balancing act," said Castro, who oversaw the Centers for Disease Control and Prevention's tuberculosis effort for two decades through 2013. "We won't be able to maintain physical distancing forever."

—Nathan Layne

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