Syracuse, N.Y. — Gi Desia felt so awful during a concert in mid-January she left and went home. For three weeks, she battled a slight fever, chills, body aches and earaches.

A week after she felt sick at the Westcott Theater, so did her husband. They thought it was the flu, but after the coronavirus pandemic began to build in New York, they wondered if they might have been among the disease’s first victims in Central New York.

On Monday afternoon, they stood in line for three hours to find out.

“For me, knowing that I had it is important because there may be future ramifications of the virus,” said Desia, one of 150 people tested by the state health department at Wegmans on James Street. “If there are any future secondary complications, at least I’ll know if I had the virus.”

The Wegmans, and the Price Chopper on Erie Boulevard, were among dozens of locations across the state where the health department conducted surprise testing to track the spread of the virus. Gov. Andrew Cuomo announced on Sunday the state would conduct 3,000 antibody tests, but health department officials say they might end up with more. Several hundred of those are likely to come from the two Syracuse testing centers.

The department is seeking a broad sample representative of the New York’s 19 million residents. The results could help decide when to get the economy moving again.

By the time of Cuomo’s announcement, the health department was quietly setting up shop at Central New York supermarkets. At the Price Chopper late Sunday afternoon, the test site was marked only by a hand-written sign on newsprint. There was nobody in line, said Syracuse resident Jeffrey Tamburo, who happened to be shopping there.

He decided to take the test: a finger prick that rendered two drops of blood.

“I didn’t even know it was happening in our county,” Tamburo said. “There was hardly anyone there.”

After social media posts and media coverage, however, the two sites got crowded Monday. The Wegmans site had to turn away people who had been waiting for hours, Desia said.

The state is hoping to map the spread of the disease by finding out who has been infected. The blood tests search for antibodies the body manufacturers to fight the coronavirus, formally known as SARS-CoV-2. If you have those antibodies, known as IgG, it likely means were infected with that virus three or more weeks before. It doesn’t tell you if you have an infection right then. For that you need a nasal swab tests to diagnose an active infection.

While scientists believe those antibodies will provide some protection against the virus later, it’s too early to be sure.

“This won’t be known until people who have IgG levels are exposed again to SARS-CoV-2 and we can study whether any of them are infected again,” the health department said in a sheet handed to the people who were tested.

The antibody tests could help the state figure out how many New Yorkers have had the coronavirus, Cuomo said Sunday.

“Any plan to start to reopen the economy has to be based on data and testing, and we have to make sure our antibody and diagnostic testing is up to the scale we need so we can safely get people back to work,” Cuomo said. “This will be the first true snapshot of what we’re dealing with."

Testing sites weren’t announced in advance, health officials said, to prevent large crowds and give better odds of a random sample. That led to some complaints on social media from people who found out too late to get a test, and from public officials who were surprised when the testing sites sprung up.

State officials notified Onondaga County Executive Ryan McMahon ahead of time of the two locations, said county spokesman Justin Sayles.

“I think they picked two high-traffic areas where they could get demographic diversity,” McMahon said.

Onondaga County has had 646 confirmed cases of COVID-19, but experts believe the number of people who have been infected is far higher. Upstate Medical University estimates about 8,600 people, or about 1.3% of the Central New York’s population, have had the virus. The state’s testing will get a better handle on those numbers.

At the Wegmans on James Street, the department set up a four-station testing center in the food court, near the front doors. Desia said she provided identification and medical information, and then a nurse pricked her finger and squeezed two drops of blood onto a card.

Desia was told she’d get a call in three to five days with the results.

Desia said she and her husband arrived about 1:30 p.m. Monday, and there was already a long line in the parking lot. Everybody wore a mask, she said, and stayed at least six feet apart. Wegmans employees patrolled the parking lot, instructing people to stand on the parking stripes to maintain enough distance.

For the next three hours, Desia stood in the slowly moving line, chatting with people in front and behind. Of the dozens of people she talked, to, Desia said, nearly all of them had been sick at some point with symptoms resembling COVID-19.

“Not one person I spoke with had been tested to see if they were positive or negative,” she said.

The crowd was smaller Monday afternoon at Price Chopper, said Kay Scott, who went there late Monday afternoon to get tested. A nurse practitioner, she had worked in Upstate Medical University’s department of infectious disease research and is now a substitute school nurse. She and her husband had traveled to New York City several times for his medical treatment. Scott said she had had mild symptoms similar to COVID-19’s and wanted to know if she had had the virus, possibly exposing her three teenagers.

“I’m essentially the canary in the coal mine for my family,” she said. “If I’m positive or if I had been exposed to the virus, it may provide a clue for our own family.”

Scott said there were about eight people in front of her. She noted that the nurses taking blood samples were using the same 7-by-4-inch cards hospitals use to do heel-prick blood tests for newborns. The cards even had a drawing of a heel. The cards will be shipped to the health department’s Wadsworth laboratory in Albany, which developed the test.

Tamburo, who was tested Sunday afternoon, got his results back within 24 hours. He was neither positive nor negative, he said, but “indeterminate.” The health department said that can happen if the test reacted with other antibodies, or if the coronavirus antibody levels are too low to measure.

The health department told Tamburo, who never had any COVID-19 symptoms, he could get tested again Monday.

“I went back to Price Chopper yesterday,” he said, “but there was a huge line all the way through the produce section.”

He left.

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