Cam Newton tests positive for COVID-19, prompting NFL to postpone Patriots-Chiefs game

Cam Newton is the first Patriots player to land on the COVID-IR.Matthew J. Lee/Globe staff

KANSAS CITY, Mo. — The much-anticipated Sunday showdown between the Patriots and Chiefs has been postponed until Monday or Tuesday after New England quarterback Cam Newton, and a player on the Kansas City team tested positive for COVID-19, a league source confirmed Saturday.

Newton is the only Patriot to test positive this season and the club officially placed him on the COVID injured reserve list later in the day. He cannot return to practice or game action for five days and likely longer, depending on his symptoms.

The Chiefs also have a positive test, according to reports: practice-squad QB Jordan Ta’amu, who coincidently had the role of mimicking Newton during the club’s preparations this week.

The Patriots scheduled a virtual meeting for 7 p.m. Saturday, when the team’s plan to deal with the situation was to be spelled out, a league source said. Later Saturday night, ESPN reported all other Patriots players' tests came back negative, according to Adam Schefter. And ESPN’s Dianna Russini, citing sources, earlier reported that the league planned to play the game Monday night. There was no word, however, on the Chiefs' test results.

The team revealed late Friday night that a player — later identified as Newton — had tested positive. The team has not offered any details on whether he had begun to show symptoms, or how he might have been infected. He was tested Friday morning, the team said.

In the wake of the Newton test result, all of the Patriots players and coaches took two coronavirus tests Saturday morning, according to a source familiar with the team’s testing. The first round of tests — the kind which yield rapid results — all came back negative. The team expected to receive the results from the second test later Saturday.

While the possibility exists that more tests could come back positive because of the disease’s incubation period, it’s also possible Newton’s result could be an isolated one.

Coronavirus testing has inherent limitations, infectious disease specialists cautioned, when asked how the Patriots should respond to Newton’s positive test, and his teammates' first round of negative results.

People could be infected with the virus, and spread it, for two or three days before the virus can be detected in a test. And people who are in close proximity, as players are likely to be in team facilities and on planes, can easily transmit the virus, especially if they’re not wearing masks.

Uncertainty is the only certainty. Last week, for instance, Falcons corner A.J. Terrell returned a positive test, but all the other Atlanta results (players, coaches, staff) came back negative. The Falcons and Bears played their game and no player from either team has gotten sick.

Under league protocols, Newton will be out at least five days, allowed to return after that if he remains asymptomatic and has two negative test results at least 24 hours apart. Otherwise, he will be out at least 10 days. The length of the wait depends on his symptoms; if he shows signs of COVID-19, he will be barred from returning to the team for 10 days after 72 hours of being symptom free.

The Patriots said in a Saturday morning statement they received notice “late last night” that a player received a positive test result.

"The player immediately entered self-quarantine. Several additional players, coaches, and staff who have been in close contact with the player receiver point of care tests [Saturday] morning and all were negative for COVID-19,'' the team said. “We are in close consultation with the NFL, as well as our team of independent doctors and specialists, and will follow their guidance regarding our scheduled trip to Kansas City and game against the Chiefs. The health and safety of our team, as well as our opponent, are of highest priority.”

The team had planned to fly to Kansas City Saturday, but the flight was cancelled.

In deciding to postpone the game, the league said in a statement: “In consultation with infectious disease experts, both clubs are working closely with the NFL and the NFLPA to evaluate multiple close contacts, perform additional testing and monitor developments. All decisions will be made with the health and safety of players, team, and gameday personnel as our primary consideration.”

News of the positive tests in New England and Kansas City comes days after the Tennessee Titans experienced an outbreak, forcing the postponement of their scheduled Sunday game against the Steelers to Week 7.

The testing of Patriots players and other staff on Saturday may not offer a final reading on the risks the team members face, specialists said.

A positive test for one player doesn’t answer critical questions, said Dr. George M. Abraham, chair of the Infectious Disease Board of the American Board of Internal Medicine.

“How infectious was he for the three days leading up to this? Could others be harboring virus who tested negative today but will test positive tomorrow?” said Abraham, who is chief of medicine at Saint Vincent Hospital in Worcester. “Any negative test today does not in any way confirm that they are not infectious and now harboring the virus.”

Newton should isolate and those who came in contact with him should quarantine, Abraham said. “Postponing the game is the appropriate response.”

Dr. Nahid Bhadelia, a Boston Medical Center infectious diseases physician, agreed that the game had to be postponed.

People who have spent more than 15 minutes within six feet of Newton “need to quarantine,” she added.

Any testing strategy “has to be paired with physical distancing and masking if you want to guarantee no infections,” she said.

But Dr. Rochelle Walensky, chief of infectious diseases at Massachusetts General Hospital, said the appropriate response to the positive test “depends on the context.”

The US Centers for Disease Control and Prevention recommends that anyone who was within six feet of a person who has tested positive should quarantine for 14 days.

But those guidelines are for the general public, and do not address conditions where there is access to frequent testing, she said.

“We really are in a data-free zone when it comes to how long you should quarantine in the context of very rapid sequence routine testing,” Walensky said. “As with the president and the NFL, there’s a little more at stake than for a random person staying home for 14 days.”

That situation calls for a more nuanced response that depends on how many people were in close contact with Newton when he was most infectious, how frequently tests are done, what tests are used, and how well those tests detect true disease.

The team’s medical advisors know such details, Walensky said, adding, “I know many of them and I trust them.”

With the dynamic Newton sidelined, much will change on the playing field. The Patriots will look to veteran Brian Hoyer to fill in as the starter. He has been Newton’s backup through the first three weeks. Jarrett Stidham, who is third on the depth chart and has been inactive for all three games, would be the backup.

After a pair of injury-riddled seasons, Newton has been one of the league’s top stories, leading the Patriots to a 2-1 start — and coming within 1 yard of a touchdown that would have made them 3-0. The 10-year veteran and former MVP is 62 of 91 for 714 yards and pair of touchdown passes. Newton, the best dual-threat quarterback the league has ever seen, also has rushed 35 times for 149 yards and four scores.

The coronavirus threat has loomed over every aspect of this strange and unprecedented sports season.

Earlier this week, coach Bill Belichick was asked about the testing and safety protocols in place in light of the outbreak in Tennessee.

“We monitor everything every day,” Belichick said. “We don’t just do it when there’s a problem or something comes up somewhere else. We do it on a daily basis and make everyone — because this is everybody, it’s not just the players; it’s players and coaches and staff and everybody else — make everyone aware. Or if we can do something better, then we talk to them about how we can do it better. So, we try to monitor it the best we can."

(Globe staff writer Nicole Yang contributed to this report.)