Carrie Moran made the cold call while Maria Ramirez, a Spanish-speaking health assistant, crouched over the speakerphone at the edge of the desk.

“Did they call you yet with your results?” Ramirez said, interpreting for the Maryland man in his 30s on the other end of the line. He said no.

“We’re calling to let you know that you tested positive for covid-19.”

“Oh, sí,” the man replied softly after a pause.

“Sí,” Ramirez repeated.

Thirty-five minutes later, Moran, a school nurse supervisor whose schools are closed because of the pandemic, had notes about the man’s symptoms, his living arrangements, his job and his whereabouts since he fell ill.

Similar calls are being made across the country, from California to Massachusetts. As states start to emerge from the strict shutdowns imposed as part of the effort to fight the novel coronavirus, they are scrambling to hire tens of thousands of people to trace the path of the deadly infection. Notifying those who have been exposed — and persuading them to isolate and get tested — has been a vital part of curbing the pandemic in countries around the world, including South Korea and Germany, public health experts say.

Local leaders in Maryland and top Democrats in Annapolis have accused Gov. Larry Hogan (R) of moving too slowly to hire contact tracers through the University of Chicago’s National Opinion Research Center (NORC). Filling the gap, for now, are people like Moran, part of an army of school health workers deployed by the Anne Arundel County government.

Over the course of a week, Moran and her colleagues made contact with the 30-something man’s relatives and tried to track down his boss, along with hundreds of others exposed to infected patients.

Some of their targets do not return calls. Some say they cannot afford to stay home from work or are reluctant to give information for contacts. And others have no idea when or where they may have contracted the virus, making it hard to determine who they might have infected.

Karen Karnes, supervisor of the county’s epidemiology program, said people have abruptly hung up on contact tracers, then called back to apologize. She said she understands that it sometimes takes time for people to process the fact that they are infected and what that might mean.

“It can be a real struggle,” she said. “It’s important that contact tracers are really good listeners, be empathetic and talk to people on a level that they feel comfortable, providing them with the education that they need to understand this disease.”

Detectives and social workers

While tests identify who has the coronavirus, contact tracing — a public health practice widely used in underdeveloped countries but only marginally in the United States — determines how far it has spread.

“If you don’t know where the enemy is, how are you supposed to beat it?” asked Anne Arundel County Executive Stueart Pittman (D).

According to a recent study, a person with the coronavirus can, on average, infect two to three other people, each of whom is likely to infect two or three more. Through 10 iterations, that means one positive case can turn into more than 59,000 infections.

The study, from the Johns Hopkins Center for Health Security, says the United States needs a large-scale effort of about 100,000 contact tracers to identify all coronavirus cases and trace all close contacts.

A spokesman for Hogan said Thursday that Maryland has hired 650 contact tracers who will be “fully operational” as of next week, joining nearly 800 locally hired contact tracers throughout the state. In Virginia, Gov. Ralph Northam (D) said the state is in the process of expanding its tracing force from 300 to 1,300. The District has hired an additional 130 contact tracers to meet its goal of 200 for the first phase of its recovery. Mayor Muriel E. Bowser (D) said the new hires should finish training by June 1.

Anne Arundel, a largely suburban county of more than a half-million people on the shores of the Chesapeake Bay, is already paying almost 100 school nurses and others to do the work. In two months, the team grew from six registered nurses to 86 nurses, health assistants, bilingual support staffers and behavioral health specialists.

“The governor is talking about it now, as they plan a pilot program with NORC,” Pittman said earlier this week. “We’ve been doing it.”

County Health Officer Nilesh Kalyanaraman described the team’s mission as a mix of detective work and social work. Along with ferreting out who may have been exposed, contact tracers have found themselves consoling the grief-stricken and locating resources for families who need food, shelter, diapers, formula or medical assistance.

“We should call it contact-tracing case management,” Pittman said. “We’re doing case management on every one.”

Moran gathers details about her patients and anyone with whom they may have been in proximity for more than 10 minutes — the amount of time in which exposure is possible, according to the Centers for Disease Control and Prevention. She calls daily to monitor their condition and remind them to remain isolated in quarantine.

Joshua Sharfstein, vice dean for public health practice and community engagement at the Johns Hopkins Bloomberg School of Public Health, praised the county’s early launch of contact tracing and its focus on black and Hispanic communities and other vulnerable populations.

Contact tracing for Anne Arundel’s first known case — a woman in her 70s from Montana, in town to visit relatives — centered on those family members. The trail in other cases has led to a party attended by an infected person, a military base and a doctor’s office. “We did put the people from the party on quarantine,” Karnes recalled.

She said it is nearly impossible to pinpoint where an infected person was exposed, unless it is traced back to a family member or co-worker. But still, they try.

“It’s kind of difficult,” she said of coming to a conclusion that a person may have become infected during a trip to the grocery store or the bank. “Even with salmonella, you ask: ‘You ate here? You ate there?’ You try to figure it out, but you really can’t.”

One of the team’s most challenging cases originated in a house divided into four apartments. Sixteen people lived there. After a man in his 40s died and posthumously tested positive for the coronavirus, 13 other occupants — ages 8 through 70 — tested positive, too.

The grieving relatives were reluctant to provide information to contact tracers, Karnes said. Others in the home, many of whom spoke Spanish, expressed a distrust of government.

“For some of the teenagers, it was difficult to have them understand the need to stay in the home,” she said. “One of the girls had a job. She was concerned about her family, and we wouldn’t let her go to work.”

This week, the contact tracers were working on 855 cases, their biggest caseload since the outbreak. They average about 75 new cases a day, Kalyanaraman said. The county expects to bring on additional employees from government or the local community college as the number of positive cases mount. The disease-prevention bureau is also looking at how technology could play a role.

Waiting for the 'happy bin'

On the corner of Moran’s desk is a black plastic file holder her team has dubbed the “happy bin.” It is the home for closed cases, ones in which the patient is healthy and the contacts are cleared.

“One down,” a nurse said one recent day, walking into Moran’s office waving a file and dropping it in.

But dozens more yellow folders remained in Moran’s pile. One belonged to the man in his 30s.

He told Moran in their initial conversation that he had been staying in a separate bedroom for four days, away from his wife, 6-month old daughter, brother and two dogs.

Moran told him it was crucial that he remain isolated — even from his pets.

The man had started running a fever five days earlier. Worried that he might have the virus, he stopped working at his job at a grocery store in Hanover. His fever continued, and he went for a coronavirus test.

Over the weekend, the man said, his chest tightened and his heart began to race. He later realized it was an anxiety attack.

On that Saturday, his wife took the baby to the emergency room because her temperature had spiked. His wife had a fever, too. Both were tested.

Moran repeated that the man should stay away from his family. She asked whether he had a separate bathroom. He said there was a half-bathroom and he washed it down with bleach whenever he used it.

She asked what type of interaction he had with people at work. He said he worked quality control and his contact was limited to the truck driver delivering food. Moran took the name and number of his supervisor and suggested that he contact his bosses to let them know he was sick.

A week later, Karnes said the man’s daughter, wife and brother all had tested negative. But the supervisor at the store had not returned Moran’s calls, so she did not know whether he had any symptoms or should isolate.

And, despite Moran’s insistence, the man, wearing a mask, had left his room to play with his daughter, potentially exposing her to the virus again.

“We’re just trying to reinforce to him why he needs to stay isolated,” Karnes said of the efforts made by the contact tracers.

The man was now feeling better and had been removed from isolation. But the file had not made it to the “happy bin.” The man’s wife, brother and daughter had mild symptoms and remained in quarantine.

Fenit Nirappil and Antonio Olivo contributed to this report.