The 2020 Chicago Marathon has been cancelled due to ongoing health concerns amid the coronavirus pandemic, organisers announced on Monday. 

The annual event, which was scheduled for October 11, is the third major marathon in the United States to be called off amid the COVID-19 outbreak.

The New York Marathon previously cancelled its planned November 1 running and the Boston Marathon was postponed from April 20 to September 14 before ultimately being shelved. 

Chicago's marathon generally attracts approximately 45,000 participants and more than one million spectators. 

"Like all Chicagoans, I'm personally disappointed that this year's event won't take place as originally planned," Chicago Mayor Lori Lightfoot said in a statement.

"However, we look forward to welcoming all runners and their cheering squads once again when the Chicago Marathon returns to our city in full force for another very exciting race." 

Event organisers said all registered participants for the 2020 race can either have their entry fee refunded or used for the 2021, 2022 or 2023 editions.