All 30 Major League Baseball teams must name COVID-19 compliance officers in light of 18 members of the Miami Marlins' traveling party (including 16 players) testing positive for COVID-19 in recent days, per ESPN's Jeff Passan:
"...Major League Baseball is encouraging players not to leave hotels in road cities except for games, mandating the use of surgical masks instead of cloth masks during travel and requiring every team to travel with a compliance officer who ensures players and staff properly follow the league's protocol, sources told ESPN."
Passan also outlined some of the responsibilities that COVID-19 compliance officers will have for each ballclub.