Workers at one of Singapore's major container terminals are to be tested for Covid-19 after the facility became the site for the city-state's latest virus cluster.

The Covid-19 cluster involved four port workers that were working at PSA International’s Pasir Panjang Terminal, according to Singapore's Ministry of Health (MOH).

A PSA spokesman said the company had "stepped up measures to prevent the further spread of virus" while minimising disruptions to port operations.

PSA said three workers were found to have Covid-19 last month with a fourth employee detected earlier this week.

Two of workers are lashing specialists while one is a lashing supervisor. They handle wharf-side operations, as well as the lashing and unlashing of containers onboard vessels.

PSA said the latest infected worker was a haulier driver who transports containers between PSA’s Brani and Pasir Panjang Terminals.

“All four cases had been at Pasir Panjang Terminal,” a PSA spokesman said. “PSA is working with the authorities on contact tracing and testing.”

PSA said that since the outbreak of Covid-19, its precautionary measures have included lashing teams donning personal protective equipment (PPE) before boarding vessels and strictly staying within their work areas when on board.

The port operator said it has also implemented a contactless segregated mode of cargo operations to avoid contact between vessel crew and lashing teams.

“This is to safeguard the health and safety of both parties while continuing with operations at our terminals,” the PSA said.

Singapore recently prohibited crew changes for seafarers with recent travel to India, Bangladesh, Pakistan, Sri Lanka and Nepal due to the spike in Covid-19 cases in those countries.

The ban includes sign-on crew travelling to Singapore by aircraft, as well as sign-off crew from vessels that have called at the four South Asian countries. It also applies to sign-on crew transiting these countries on their connecting flights to Singapore.

The Maritime and Port Authority of Singapore said the ban on crew changes was is in line with the new policy from the Ministry of Health, which stated that all long-term pass holders and short-term visitors with recent travel to these five countries in the last 14 days will not be allowed into the country.