SINGAPORE - Eight bus drivers have tested positive for Covid-19 as at July 30, said the Land Transport Authority (LTA).

The Straits Times learnt that some drivers who had been in contact with confirmed cases were placed on quarantine or stay-home notices in recent weeks.

Responding to queries, the LTA told ST these measures affected less than 1 per cent of the 9,500 bus drivers.

There has been no impact on bus operations, it added.

The LTA did not give details on how many drivers had been quarantined or if the confirmed cases were linked to one another.

It also said more than 99 per cent of bus drivers have completed their first dose of the Covid-19 vaccination.

Public transport operators have also been proactively administering antigen rapid tests on workers based near locations of active coronavirus clusters, it said. This is to pick up potential infections early.

"We will continue to work closely with public transport operators to ensure safe management measures for both workers and commuters are strictly adhered to," LTA added.

"In addition, the operators will continue with their stepped-up daily cleaning and disinfection regime for public transport nodes and vehicles."

Last year, several SMRT bus drivers were linked to a Covid-19 cluster at Bukit Panjang Integrated Transport Hub. Around 11,000 people were subsequently screened for the virus as a precautionary measure.

In May this year, the authorities said that public transport, such as trains and buses, is "well-ventilated through mechanical and/or natural fresh air intake".

Combined with stepped-up cleaning regimes and mask-wearing, this will minimise commuters' exposure to the virus, they added.

Infectious disease experts concurred, saying that the risk to passengers is likely to be low, given that interactions with bus drivers are transient and mask-wearing is compulsory.

"All these will reduce the risk of transmission, as will the air flow exchange that happens when the air-conditioning systems in the buses are operating," said Professor Teo Yik Ying, dean of the National University of Singapore's Saw Swee Hock School of Public Health.

Those who are still concerned can ensure they are wearing quality masks and take buses at less busy times, suggested infectious diseases specialist Leong Hoe Nam.

"Try to do social distancing within the bus. This is frequently not possible, but every little bit helps," he said.

"The option to wear a good mask is in your hands. Remember that healthcare workers have protected themselves consistently with good quality masks."