Axios

Major League Baseball announced in a statement Sunday that it has postponed the St. Louis Cardinals' three-game series against the Pittsburgh Pirates, set to start Monday, because of a coronavirus outbreak.

Why it matters: St. Louis has had 13 games in a row postponed after seven players and six staff members tested positive for COVID-19 last week. The MLB announced Friday another Cardinals staff member and two more players tested positive for the virus. The MLB said "in light of the most recent positive test results," the league and the Cardinals "believe it is prudent to conduct additional testing while players and staff are quarantined before the team returns to play."

Go deeper: How baseball's coronavirus reckoning affects everything

Former FDA commissioner Scott Gottlieb said on CBS News' "Face the Nation" that the coronavirus death toll in the U.S. will be "definitely" somewhere between 200,000 and 300,000 by the end of 2020.

Why it matters: "Whether we're closer to 200,000 or closer to 300,000 depends on what we do now and how it evolves," Gottlieb warned on Sunday as the U.S. surpassed five million confirmed coronavirus cases.

Ohio Gov. Mike DeWine (R) said on CNN's "State of the Union" Sunday that Americans shouldn't think testing for the coronavirus is "not reliable or doesn't work," after he received a false positive result from an antigen test last week.

Why it matters: DeWine is one of six governors who have agreed to pool their resources, along with the Rockefeller Foundation, in order to acquire 3 million antigen tests amid severe delays and the lack of a national testing strategy.

Six students and three staff members have tested positive for COVID-19 at North Paulding High School in Georgia, where a photo showing a hallway packed with maskless students went viral last week, the Atlanta-Journal Constitution reports.

Why it matters: The infections underscore the difficulty of reopening schools during the pandemic, which will require a rethinking of traditional routines in order to avoid outbreaks. The topic has become politically charged as President Trump pushes for schools to resume in-person classes in order to jump-start the economy.

Brazilian President Jair Bolsonaro posted a photo of himself to Facebook congratulating his soccer team, Palmeiras, for winning the state title Saturday, moments after the health ministry confirmed the national COVID-19 death toll had surpassed 100,000.

Why it matters: Brazil is only the second country to confirm more than 100,000 deaths from the coronavirus. On Sunday morning, it became the second country to surpass 3 million cases, per Johns Hopkins. Only the U.S. has reported more. Bolsonaro has yet to address the milestones. He has previously tested positive for COVID-19 three times, but he's downplayed the impact of the virus, which has crippled Brazil's economy.

Editor's note: This article has been updated with the latest coronavirus case numbers and more context.

Ohio Gov. Mike DeWine (R) tested negative for COVID-19 for a second time after initially testing positive last week, he announced Saturday.

Why it matters: 73-year-old DeWine was set to meet President Trump Thursday on the tarmac at an airport in Cleveland and was tested as part of standard protocol.

Some Republicans joined Democrats in criticizing President Trump Saturday night for taking executive action on coronavirus aid, with Democratic leaders demanding the GOP return to negotiations after stimulus package talks broke down a day earlier.

Why it matters: Trump could face legal challenges on his ability to act without congressional approval, where the constitutional power lies on federal spending. Sen. Ben Sasse (R-Neb.) was the most vocal Republican critic, saying in a statement: "The pen-and-phone theory of executive lawmaking is unconstitutional slop."

35% of Americans say they would refuse a coronavirus vaccine, even if it was free, approved by the Food and Drug Administration and available immediately, according to a Gallup poll released Friday.

The big picture: Health experts believe a vaccine — coupled with recommended public health measures — will be the path back to societal normalcy. But that outcome relies on a critical mass getting the vaccine so that the population can achieve herd immunity.

Thousands of motorcyclists have gathered in Sturgis, South Dakota, this week to celebrate the 80th Motorcycle Rally despite the coronavirus pandemic, AP reports.

Why it matters: Local residents fear the crowds could create a “super-spreader” event because the state government has not implemented limits on indoor crowds or mask mandates, and Gov. Kristi Noem (R) has encouraged people from around the U.S. to travel to the state. Organizers reportedly expect 250,000 people to rumble into town during the 10-day affair.

A growing body of research has made it clear that airborne transmission of the coronavirus is possible.

Why it matters: That fact means indoor spaces can become hot spots. Those spaces also happen to be where most business and schooling takes place, so any hope for a return to normality will require better ways of filtering indoor air.

Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said Friday that the chances of a coronavirus vaccine having 98% or more guaranteed protection are "not great," per CNBC.

Yes, but: The Food and Drug Administration says it's prepared to authorize a coronavirus vaccine so long as it's safe and reduces a person’s risk of a COVID-19 infection by 50%.

President Trump announced on Friday he will pursue an executive order requiring insurance companies to cover pre-existing conditions, something that is already law.

Why it matters: The Affordable Care Act already requires insurers to cover pre-existing conditions. The Trump administration is currently arguing in a case before the Supreme Court to strike down that very law — including its pre-existing condition protections.