Passengers look at a screen to find where airlines check-in desks are located at the departure hall in Hong Kong's Chek Lap Kok International Airport

covid covid19 coronavirus variant spread virus illness pandemic cases policy change policy changed eased restrictions rules prevention restrictions vaccine masks airport international airport travel hong kong airport terminal hall leaving departure departing departure hall economy tourism immigration business open up passengers travelers chinese travelers arrival arriving arrival hall walking chinese citizens landing chinese passengers leaving airport china travel industry screen checkin screen airline check in airline screen