A total of 2,430 people were tested at two blocks in Phase Three of Kwan Yick Building on Des Voeux Road West in Sai Ying Pun, as well as Hoi Kung Court and Hoi To Court on Gloucester Road in Causeway Bay.
An official said one person will have to be retested.
The operations were announced after the Centre for Health Protection said confirmed cases had recently emerged from these residential blocks.
The government had said there was a high risk that the virus could spread in these areas because of the age of the buildings, as well as the prevalence of sub-divided units inside the blocks.
The operations were wrapped up between 7 and 8 am and people were allowed to leave the buildings concerned.