Walt Disney Co welcomed a limited number of guests on Saturday to its two most popular parks at the sprawling Orlando complex, the world's most-visited theme park resort, with a host of safety measures designed to reassure visitors and reduce the chances of catching the sometimes deadly virus.

At the Magic Kingdom and Animal Kingdom, the two parks that reopened Saturday, guests and employees wore face masks, underwent temperature screenings and were told to social distance everywhere from streets to rides.

Plexiglass separated rows in lines, and ground markings indicated where people should stand.

Epcot and Disney's Hollywood Studios, the two other Walt Disney World parks, are scheduled to reopen on Wednesday.

The resort suspended parades, fireworks and other activities that create crowds, as well as up-close encounters with Mickey Mouse, Cinderella and other characters. Instead, characters appeared on floats or on horseback.

Some pictures online showed people close together waiting to get in. Disney employees, called cast members, began enforcing distancing requirements after about 30 minutes.

Other videos showed people inside staying apart, cheering, taking selfies and enjoying the park without long lines.

Florida has emerged as an epicentre of COVID-19 infections. Over the past two weeks, the state reported 109,000 new coronavirus cases, more than any other US state.

Still, many Disney fans and workers were eager for Disney World to open its gates. The resort employs 77,000 people.

Australian Associated Press