From Monday, frontline terminal employees will be tested every three days if they are fully vaccinated – and every day if they are not – within 21 days after disembarkation from ocean-going cargo vessels.
The same requirement will be extended to cover those working at other terminals and other frontline staff in the ship services sector a week later.
The authorities said new testing stations will be set up in Sheung Wan, Tuen Mun and Yau Ma Tei, apart from the existing ones in Kwai Tsing and Tsuen Wan West.
Meanwhile, health officials reported one imported Covid-19 infection on Sunday, involving an air crew member arriving from Germany a week ago.
The 53-year-old Cathay Pacific staff was found to be carrying the L452R mutant strain.
He received his third dose of BioNTech vaccine on Thursday.
His infection prompted a lockdown at his residence at Hampton Place in Tai Kok Tsui overnight, but no other patients were found.
The government has said it would tighten anti-pandemic measures for flight crew members after they were among the latest imported Covid cases.