What the Miami Marlins’ Covid-19 outbreak means for the MLB season, explained by an epidemiologist

“If we’re able to bring sports back in the US, it’s going to be more difficult, more expensive, and more dangerous.”

Mere days after its belated beginning, the 2020 Major League Baseball season is already in a heap of trouble, because of Covid-19.

On Monday, news broke that 11 of the 33 Miami Marlins players who traveled with the team to Philadelphia for the opening series that took place from Friday to Sunday tested positive for the virus, as well as two coaches. That news prompted the MLB to postpone two games that were scheduled for Monday evening: the Marlins’ home opener against the Baltimore Orioles, and Philadelphia’s contest against the New York Yankees (the Yankees will be using the same clubhouse that the Marlins did over the weekend while the coronavirus was apparently spreading among the team). Miami’s scheduled game on Tuesday has been postponed as well.

Then, on Tuesday, news broke that four more Marlins players tested positive, bringing the number of team members with confirmed cases in recent days up to 17.

News of the Marlins’ outbreak has shined a harsh spotlight on the team’s decision to play a game on Sunday against the Phillies, one that started just hours after the Marlins’ projected starting pitcher, José Ureña, was scratched because of a positive Covid-19 test. The Philadelphia Inquirer reported that players made the call to play in a text message chain, without input from Major League Baseball.

But it shines an even harsher one on the MLB writ large: Unlike the NHL and NBA, the MLB is not confining players to a “bubble.” While the games are being played in empty stadiums and teams must observe strict protocols on game days, players are traveling between cities and leaving ballparks for their homes or hotels each day. Monday’s news doesn’t bode well for those hoping that sports outside of a bubble-like environment are sustainable in a US where the coronavirus has raged out of control.

Given the rash of positive test results on Sunday and Monday, it’s likely that some Marlins players who took the field on Sunday had the virus. The Phillies’ scheduled game on Tuesday was postponed as the team awaits test results.

Despite all that, New York Post sports media columnist and former Baseball Tonight contributor Andrew Marchand said that at this point, he expects the MLB to try to forge ahead — but that could change if, say, it turns out that Miami taking the field while the team was amid an outbreak resulted in another team having an outbreak.

“I think MLB will try to play through. I don’t see them canceling the season at this point, though, a pause could be considered,” Marchand wrote in a direct message. “In my opinion, the cancellation of the season would likely happen if there were more multiple outbreaks on teams or, more severely, if someone were to become gravely ill.”

To get a sense of what the Marlins coronavirus outbreak means from both a public health and baseball perspective, I spoke on Monday with Zachary Binney, an epidemiologist at Oxford College of Emory University. Binney said he’s “really blown away and deeply disappointed by MLB’s response to all of this so far,” but added that he doesn’t think baseball needs to cancel the season — yet.

A transcript of our conversation, lightly edited for clarity and brevity, follows.

Aaron Rupar

I’m curious how unexpected all of this is. Obviously you’re coming at this more from the public health expertise standpoint than the baseball standpoint, but how surprised are you just a few days into the season that there’s already been an outbreak on this scale? Now it’s confirmed that a third of the players that were traveling with the Marlins have tested positive, so that’s a pretty high rate, along with a couple of coaches.

Zachary Binney

Well, first of all, let me say I have been following it, and I’m a big baseball fan. I work at the intersection of epidemiology and sports, more on injuries than on infections usually, but that’s my area. So I’m fairly familiar with both sides. My dad was actually a statistician for Ted Turner back from 1981 to ’86, so he covered all the Braves games for TV, so we got baseball in our blood a little bit. So it’s funny that I’m in the sports stats world too.

I was somewhat surprised at the scale and the speed of the outbreak. I was surprised that Covid-19 ripped through the clubhouse and the traveling party a little bit. The number of cases is off the charts higher than I expected.

Aaron Rupar

Do you have any sense at this point in time in terms of what might account for that? The best information I had seen is that it appears whoever the patient zero in this outbreak is might have taken it from Miami to Philadelphia. Obviously you’re not with the team, so it’s a bit speculative, but what do you think might explain the wildfire-like nature of all these players being positive over one weekend?

Zachary Binney

Well, just like you said, it’s speculative, so I don’t want to speculate too much. But what I will say is, I think it’s very important for Major League Baseball and the Marlins to conduct a swift but thorough epidemiological investigation to figure out just what happened, and how this disease spread as quickly and widely as it did. Was it players and staff engaging in risky behaviors away from the clubhouse, such as going out together to a bar or a nightclub? Was it mostly spread within the clubhouse or the dugout? And if so, what led to that? Was it some weakness in Major League Baseball’s protocols, or was it a lack of adherence by the Marlins to baseball’s protocols?

Depending on the answer, you have pretty different implications for how you proceed. The other possibility is that, look, MLB’s protocols were pretty much as strong as you can make them outside of a bubble, the Marlins were adhering to those, and they simply are not strong enough to withstand operating in a market with as many cases as Miami has. It’s one of the worst areas of the country right now in terms of virus. So maybe MLB’s plan works okay in New York and Boston and Philadelphia, but not Miami.

My sense is that probably it did start in Miami just given the incubation period of the virus. There’s an outside chance they picked it up soon after they got to Atlanta [for a preseason series], so I can’t say definitively that it started in Miami, but that’s sure what it sounds like.

Aaron Rupar

What do you think, if anything, this says about the two-day turnaround time for Covid-19 tests going through the MLB labs? That doesn’t seem totally ideal in a case like this; some team members who received results on Monday played on Sunday and possibly exposed Philadelphia to the virus during the game.

Do you view that as being a problem, this delay in turnaround that can lead to a situation where players are practicing or playing in between getting the results? Would it be feasible for the MLB to use rapid testing that would give more immediate results and possibly avoid situations like this? That was one thing that came to mind processing this story — this extra day could really cause some problems. What’s your read on that?

Zachary Binney

The longer delay that you have between the test and the result is more time that someone who is positive can be spending potentially transmitting the virus to others on the team, both players and stuff. So the faster turnaround you can get, the better.

There is certainly I think some room and some discussion among my colleagues to be looking into quicker testing technologies, like these $1 to $2 paper strip tests, that can give you more or less instantaneous results — kind of like a pregnancy test, but for Covid-19. I think that would certainly be something for MLB to look into in the future. It may have helped them short-circuit the Marlins’ outbreak to a degree.

But also, you have to look at the actions of Major League Baseball and the Marlins organization here, and they don’t look good. The fact you had four positive tests, and you still played a game? That you still put the Phillies at risk, and more to the point, put people in your organization at risk by getting them together in a clubhouse and a dugout again, to play a game, when you knew there was a very real chance you had an outbreak? No testing is going to stop idiocy.

So I’m really blown away and deeply disappointed by MLB’s response to all of this so far. It’s been a lot weaker than I would’ve hoped it had been. I mean, I wrote a blog post back on June 30 warning about almost this exact scenario, where you had three or four cases, and you need to act quickly then, because if you identify three or four cases in rapid succession, there’s a very real chance that that doesn’t stay at three to four. And what did we find out this morning?

Mitchell Leff/Getty Images

So, I don’t know how much quicker tests would help. I think it would help some, certainly — anything you can do to improve turnaround time.

Aaron Rupar

To put a finer point on that, do you think the procedure should be that if there’s a positive test, any game that night should be postponed? Or is there a different number that you think should trigger that? I’m thinking back to over this weekend — as a Nationals fan, Juan Soto had a positive test and they played a game that night. Thankfully it seems like no other players tested positive.

I’m just wondering what your thoughts are on the MLB protocol and what you think the best practice should be.

Zachary Binney

With the amount of virus we have in this country, cases are going to happen from time to time. So I don’t think you should delay every single time a case pops up on a team. If you’re testing frequently enough, then the theory is that that testing should catch the cases quickly enough that it should keep one case, one case, and not let it turn into three or four or five or 14.

Obviously that’s not what we saw in Miami and that’s really concerning, and we need to do some quick but thorough diagnosis of what went wrong and led to this rapid spread — was it a poorly timed false negative, or what? I’ve been consistent for weeks in saying that if you see three or four cases in a few-day span on a team, shut it down until you can figure out what’s going on and be very certain that you have nipped any outbreak and cut the transmission chains. That’s not what happened here.

If you have reason to believe that the one case is going to stay one case — there’s no risky behavior that people have been engaging in that you know of, especially in a sport like baseball where he didn’t necessarily have close contact with a lot of his fellow players or staff members — you can definitely make a case to continue through one positive. But when you get into three or four, that’s clear evidence of an outbreak, and you’ve gotta be more cautious than the MLB was here, and the Marlins were here. So that’s the line I would draw — three to four cases in rapid succession, shut it down. The team, not the league.

Aaron Rupar

The MLB announced they’re postponing the Marlins’ game and the Phillies’ game — obviously the Marlins were just there. Do you think that’s the correct response, and how feasible do you think it is that the Marlins play as soon as Tuesday?

Zachary Binney

That would be inhumanely reckless. To have the Marlins come back tomorrow [Tuesday] would be inhumanely reckless. I would be disgusted. I would be vomiting with rage.

There is an out-of-control outbreak on this team. You cannot assume anybody in that traveling party is uninfected. You have to assume the entire traveling party is infected. So, I guess if you want to go with a just bloodless, next-man-up mentality, you could grab your entire satellite site and try to field a team from that.

But can we just have a moment of shared humanity here? A potentially serious virus is ripping through your clubhouse that’s part of a broader global pandemic. Can we hit pause here for a minute? Can we deal with that? Can we deal with the psychological fallout and the stress from that? I mean, some coaches are infected. Depending on who they are, there’s no guarantee that they’re going to be fine. There’s no guarantee that all the players will be fine, though I haven’t heard reports of any substantial symptoms yet, which is good.

You need to press the pause button for longer, and MLB needs to step in and put on its big boy pants and be the adult in the room and recognize that. I would say for two weeks. One day is laughable. If they try to take anybody from that traveling party and have them play Tuesday or Wednesday or Thursday, I don’t even have words for how reckless that would be.

They know there’s a good chance some of them are sick, and they put them on the field anyway? They would just be declaring that they don’t care. They don’t care about the health of their athletes or their coaches, or the Marlins’ opponents — the Orioles — they don’t care. And the Orioles, by the way, would be stating that they don’t care about the people of Baltimore if that game happened, because they would be bringing in a group with a known raging outbreak to stay in a local hotel.

So everybody needs to take a minute, take a step back, and look at themselves in the mirror for God’s sake. We are people — can we act like it for a minute?

Aaron Rupar

That obviously raises a lot of logistical problems from the MLB’s standpoint. It’s already a truncated season and postponing nearly a week’s worth of games is a big chunk. So what do you think this portends in terms of the prospects of MLB being able to continue on with this season?

Zachary Binney

The question you’ve gotta ask yourself if you’re Major League Baseball is, how likely do we think it is that the Marlins transmitted the infection to their opponents, the Phillies, over a three-game series? It may be unintentional, but they have run an experiment here — how easy is it for the virus to transmit from one team to another over the course of a three-game series?

If they are confident that the answer is “very unlikely,” then the Phillies should play tonight, because you can clean the clubhouse — I don’t think there’s a huge risk of the Yankees picking it up as long as the visitors’ clubhouse has been ventilated and scrubbed down to the studs. But if you think there’s a chance, then waiting one day is not enough. It’s optics, it’s fear. You need to wait five days to see if any cases are going to pop up.

So, choose one. Play tonight, which they’ve already decided not to do, or play in five days. Otherwise, the move you made was only for PR. It’s not based on any understanding of health or epidemiology or the biology of the virus. It simply is not.

Aaron Rupar

So if you had to handicap it, what do you think the odds are that this season has to be brought to a premature conclusion because the virus is so out of control that it becomes downright reckless to forge ahead?

Zachary Binney

I think if you see another situation like the Marlins — another outbreak like this, especially in the central or western divisions which have had no contact with the Marlins in the eastern division — I think you would have to think very seriously about suspending the league.

What are the chances of that? I don’t know and I don’t want to speculate. I hate trying to put numbers on this, because I really don’t know. But I’m a lot less optimistic than I was last Thursday. I mean, I was starting to get surprisingly optimistic after we didn’t have this happen during preseason training. Honestly, I thought all this was going to blow up before they played a game. But then it didn’t, and I’m a scientist — I update my opinions when more data comes in.

But I also knew that the past is no guarantee of the future. And that’s what we’ve seen here in the last couple of days.

Aaron Rupar

MLB stands in contrast to the approach taken like leagues by the NHL and NBA, where players are staying in a bubble-like environment, where players are staying in a confined space without intermingling with the general public in a way that baseball players can when they go home or go out. Is it correct to interpret this as a strike against the MLB approach? Do you think it’s much more likely that the NHL and NBA will be successful in reaching the ends of their season without a hitch, where baseball seems to be having these huge problems right away?

Zachary Binney

If you’re looking at the data, here’s what I see. I see the National Women’s Soccer League held a successful tournament in a bubble. I see that Major League Soccer had some bumps at the start — they had a couple of outbreaks when they were operating and training in home markets, in Dallas and Nashville, but those did not quite translate to blowing up the bubble.

The NBA bubble so far has looked quite successful, as has NHL’s plan, which is not only a bubble, but a bubble in Canada, which I think is another very wise thing to do — get the heck out of the United States. What you’ve also seen is MLB’s plan of testing regularly but having everybody live at home in their communities has been successful. The issue is it’s been successful in Germany and Spain and Italy and South Korea, and the US doesn’t look like any of those in terms of our response to the virus.

So I always had concerns that Germany’s plan would work here, and it looks like it’s certainly not as effective as it was in Germany. So yeah, I think you have to interpret that as a strike against being able to play sports outside of a bubble in the US, and that’s the result of our weak and poor response to the virus, and the fact that it’s so out of control.

We’re reaping what we sowed, it’s as simple as that. If we’re able to bring sports back in the US, it’s going to be more difficult, more expensive, and more dangerous. Period, the end.

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