TAIPEI - Taiwan banned large gatherings and even hospital visits on Tuesday (May 11) following the formation of a cluster of local Covid-19 infections in the north of the island.

This comes a day after China Airlines - its largest carrier - quarantined its pilots to stem another cluster.

To curb recent infections in Yilan county in the north, the authorities stepped up Covid-19 prevention measures islandwide starting on Tuesday, which will remain in place at least until June 8, said the Central Epidemic Command Centre (CECC) on the same day.

Indoor gatherings of more than 100 and outdoor gatherings of more than 500 people are banned. Hospital visits, eating and drinking on public transport are now also banned.

The cluster of infections in Yilan emerged as five people who had visited an amusement arcade tested positive for Covid-19 and were announced as new cases on Tuesday. Out of the five, four are arcade employees and one is a frequent customer.

As the CECC is still unsure how the local transmissions in Yilan began, it has decided to raise its Covid-19 alert to level two - out of a total three levels - which indicates "when local cases with unclear infection sources emerge".

Premier Su Tseng-chang said on Tuesday: "Taiwan has carried out pandemic prevention very well for the past year, but we are getting more relaxed or careless as time goes by."

"I urge everyone to take the new outbreak seriously," he added.

Similar restrictions have been imposed before, but Taiwan has never gone into total lockdown. The island, which has one of the world's best pandemic responses, has so far recorded 1,210 Covid-19 cases and 12 deaths.

The health authorities are calling on people to avoid crowded places, wear masks and abide by social distancing restrictions at gatherings.

Under the latest restrictions, event organisers need to ensure all participants provide their names and contact information. The organisers are also required to leave alternate seats empty for all participants.

Passengers taking both Taiwan Railway Administration trains and the high-speed rail will be asked to wear masks at all times; eating and drinking will be prohibited. No standing tickets will be sold on intercity trains from Saturday (May 15).

Visits to hospital and nursing home wards are banned as well.

City and county governments across Taiwan have announced that school field trips, graduation ceremonies, concerts, cultural events and exhibitions have to be put on hold until further notice. Some places - among them, New Taipei City - will limit the number of people using public gyms and swimming pools.

The Yilan cluster is most likely unrelated to the China Airlines cluster, said Health Minister Chen Shih-chung at a press conference on Tuesday.

China Airlines infections were first reported on April 20. The cluster comprises 36 cases as at Tuesday and is Taiwan's worst since the pandemic began in late 2019. So far, at least eight pilots, one flight attendant and their family members have contracted Covid-19.

The coronavirus has also spread to a quarantine hotel near the Taoyuan International Airport, infecting seven staff members and their members.

According to Dr Chen, the authorities have gained control over the hotel infections as all contacts have been traced and located.

But the China Airlines cluster is still worrying the CECC: One infected pilot had come in contact with another pilot earlier, also a confirmed case now, and had visited a hotel bar and restaurant in Taipei last week.

The CECC had asked the airline to quarantine all its pilots for 14 days from Monday (May 10), and required those who had come in contact with crew members linked to the cluster to be scheduled on shifts different from those who had not.

China Airlines released a statement on Tuesday, saying it was following the government's orders and moving to quarantine its crew in groups, staggering the quarantine so as to soften the impact on its services.

The carrier estimates that over 10 per cent of its freight operations will be affected, the statement added, potentially affecting the island's chip exports amid a global semiconductor shortage.