A Boston doctor and five friends went to Miami. All six came back sick, at least four with the coronavirus

South Beach in Miami, Florida, on Monday, a traditional time of year for winter vacationers.Joe Raedle/Getty

Dr. Joshua Ellis, a medical education fellow and emergency medicine physician at Boston’s Beth Israel Deaconess Medical Center, was excited to celebrate his 30th birthday in Miami with five of his close friends.

They had been planning the trip to Florida since late fall — long before the novel coronavirus was even a blip on anyone’s radar. They rented a house on Ocean Drive, steps away from beautiful South Beach. They bought tickets to the Winter Party Festival, a week-long event that brings thousands of gay men to Miami’s hotels, nightclubs, bars, and beaches to raise money for LGBTQ groups in South Florida.

Ellis and his friends traveled to Miami in early March — before the cascade of shutdowns, curfews, and closures that would swiftly upend American life — from all over the country: Seattle, Denver, Boston, Washington, D.C.

Since then, all six of them have gotten sick and with the same symptoms: chills, sweats, fatigue, shortness of breath. Four of them, including Ellis, already have tested positive for COVID-19, the respiratory disease caused by the coronavirus.

“All six have shown the exact same symptoms at different times. So everyone in the household got it for sure — I am 100 percent confident; it’s too coincidental,” Ellis said in an interview this week, his nose running and voice hoarse. “The fear, though, is a lot of them were actively enjoying their social life [before they felt sick] . . . going to bars, going to dinners, going and hanging out at friends’ houses, quarantining with friends.”

Ellis’s story illustrates just how quickly the coronavirus spreads between close contacts and how easily an infected person can unwittingly expose others to the virus in the absence of symptoms. New research based on data from China suggests that undetected carriers of the virus are fueling the explosive growth of the outbreak. A study published in the journal Science on Monday found that people with undocumented infections, often with mild or no symptoms, were responsible for 79 percent of confirmed cases in the early stages of China’s epidemic.

At a White House press briefing Wednesday, Dr. Deborah Birx, the president’s coronavirus response coordinator, warned “there may be a disproportional number of infections” among young adults who, while not as likely to suffer severely, still pose a danger to others, especially the elderly and those with underlying health conditions.

Ellis and another friend, Adam Vavrek, interviewed for this story said they felt groggy, but not ill after they returned home from Miami. In the meantime, they lived their lives normally before the onset of symptoms. Ellis didn’t have any shifts at the hospital, but he went out to dinner with a friend on Tuesday, March 10. He attended an event at a local health center on Friday, March 13, just hours before he started feeling sick.

Vavrek, a 35-year-old marketing employee at a large tech company in Seattle, visited his company’s office and played in a dodgeball league, also on Tuesday. He was at work on Wednesday, March 11, when he suddenly got the chills.

“I think a lot of people my age are thinking they might get it, but they’re young and healthy enough to fight it. But I think what they don’t consider is who they could potentially pass it on to, others who might not be able to bounce back as quickly," Vavrek said.

Ellis and Vavrek arrived in Miami on Thursday, March 5. By then, only three people in Florida and 200-some others across the United States had tested positive for the highly contagious and potentially lethal virus. They both left Miami on Monday, March 9.

Miami, of course, was a rollicking time. Ellis, Vavrek and their four friends packed into crowded clubs and roped-off beachfront parties, dancing shoulder to shoulder with their fellow festival-goers. They weren’t shy about their affection for one another, kissing and hugging as they enjoyed what Ellis at the time assumed would be “the last big party event in the country" as other festivals were called off or postponed in the wake of the escalating public health crisis.

But they “started to see the writing on the wall,” Ellis said, as soon as they arrived.

“There were tons of hand sanitizer being rolled out. There were a lot of warnings and things going on that seemed ominous,” he said. “But we were already there and it was just like, ‘Jesus, this is probably going to be a disaster.’ "

When he got back home to Boston on March 9, Ellis said, he felt “horrible," but he just figured he was hungover. Meanwhile, his health seemed to gradually improve. On Tuesday, March 10, his 30th birthday, Ellis had dinner with a friend at Buttermilk & Bourbon in Back Bay. They sat side by side at the bar while the bartender served them. On Friday morning, March 13, he attended the event at a local health center.

But as Friday wore on, Ellis felt worse. By Friday night, he was sicker than he had ever been in his adult life. Meanwhile, he and the five friends he traveled to Miami with exchanged a flurry of alarming text messages in their group chat: They were all unwell and three, including Vavrek, had already been tested for the coronavirus and were waiting for their results.

Vavrek, who had begun feeling ill on Wednesday, March 11, left his near-empty office around noon and went home in an Uber. He had the chills, so he covered himself in blankets and went to sleep. At first, Vavrek thought he was just exhausted from his recent travels. Before his trip to Miami, he had been vacationing in Brazil and Peru for two weeks. He redirected his flight from South America to Miami, instead of Seattle, where dozens of new infections and deaths linked to the coronavirus had spiked. But when he woke up on Thursday morning, he had the sweats, a fever, head and body aches. He wondered if he might actually have COVID-19.

That Thursday, Vavrek called his primary care doctor’s office and explained why he might be sick. He was initially told to self-quarantine for seven days, but Vavrek pushed back and asked to get tested for the coronavirus. His doctor must have agreed, because Vavrek got another call later that day, telling him to report to Swedish Medical in Seattle within the hour. Vavrek snapped on a face mask and walked to the hospital, where he was tested for both influenza and COVID-19. The test for the flu quickly came back negative. He was told he would get his results back for the coronavirus test in three to five days.

On the morning of Saturday, March 14, Ellis was still sick with a cough and shortness of breath. A friend from Washington, D.C., who had traveled to Miami with Ellis and Vavrek texted the group and confirmed that he and his partner, who had also gone on the trip, had tested positive for COVID-19. (The Washington, D.C., friend declined an interview.) Right away, Ellis knew he had to get tested, too. He alerted his fellowship director and the doctor he had dinner with on his birthday. He made arrangements that evening to get tested at a local health center.

“It was scary to be honest,” Ellis said. “It was dramatic.”

He pulled up in his car in the ambulance bay, where a health care worker slipped him a face mask through the crack in his window. Then he walked straight to a negative pressure room, where he was forced to communicate to his providers through a phone line. The doctor who came in to examine him wore full protective gear.

He only stayed for an hour. As a physician, he said, he knew he could manage his symptoms at home and didn’t want to risk getting anyone else at the hospital sick. Like Vavrek, Ellis was tested for both influenza and COVID-19. He was told he would hear from the hospital with his test results in three to four days.

Back in Seattle, on the evening of Sunday, March 15, while Vavrek was eating dinner, a blocked number rang his cellphone. He let the call go to voice mail. It was his doctor. When Vavrek called her back, his doctor confirmed he was, indeed, positive for COVID-19.

“I told her I was a little nervous and anxious and she basically said I’m healthy and young and I’m already getting over the symptoms,” Vavrek said. “She flat out said I’m not going to die from this.”

His doctor told him he needed to isolate for at least seven days after getting tested and longer if he still showed symptoms. Vavrek also had to let everyone he could have possibly transmitted the virus to — including his dodgeball league and the friends he partied with in Miami — know about his infection. For Vavrek, the relief of knowing his diagnosis was bittersweet. Before getting tested, he had plans on Wednesday, March 11, to have dinner with his parents for his father’s 65th birthday — but he had to cancel.

“I tried to rest up because I wanted to celebrate his birthday with him and I ended up canceling a couple hours before. At that point I didn’t think I had it; I just thought I was exhausted from the trip," he said. “I told them if there’s any small chance that I could have it, the last thing I want to do is pass it on to my dad, who has a history of heart issues, and I’d never be able to forgive myself if I hurt my parents in that way.”

Ellis got his positive test results back in Boston on Tuesday afternoon. He’s feeling much better but he still plans to self-isolate for another 14 days. Then he will be back in the emergency department at Beth Israel Deaconess Medical Center, working on the front lines of the pandemic.

He described feeling “hopeless” when he thinks of all the people who may have gotten caught in their web of transmission.

“It takes five days for symptoms to show up and then it takes three or four days at best for the test results to come back, so that’s nine days of contact with an infinite amount of people,” Ellis said. “And all those people would have to self-quarantine and wait for either symptoms or test results, which would be another nine days.”

He said he’s enraged watching friends and strangers on social media — posing for selfies on their cheap flights, going out to the bars and hosting “quarantine parties” with dozens of people — because they could be unknowingly spreading the virus, too.

“You need to self-quarantine now. I can’t stress it enough. I’ve never been so angry about people not following the rules,” Ellis said. “There’s just no way to prevent this from getting to every corner of the country unless you self-quarantine.”