Due to COVID-19 Shanghai Disneyland has been closed since late January. Today the Walt Disney Company announced that Shanghai Disneyland would reopen on May 11th. Shanghai Disneyland Hotel, Disneytown, and Wishing Star Park resumed limited operations on March 9th with several health protocols in place. These included temperature checks, use of Health QR Codes, and social distancing measures. They had also been testing social distancing measures for ride queues, restaurants, and shows.
According to Disney Parks Blog they will be implementing “new and enhanced health and safety measures reflecting the guidance of local health and government authorities”

Every guest entering Shanghai Disney Resort is required to undergo temperature screening procedures and present their Shanghai QR Code. Only guests with a green Shanghai QR Code are allowed to enter the resort. Guests are required to wear masks at all times (except when eating) and are to follow social distancing recommendations. @gourmetdyy shared these photos on Twitter. He claims they are from line-up areas before security check. Several other sites are sharing them as measures being used. I can not verify these photos so will not say that they are indeed from Shanghai Disneyland. There is A LOT of unofficial information out there so just keep that in mind.