Some 17,100 volunteers have stepped forward to join Singapore's Covid-19 fight.

Of those who have signed up as at June 11, more than 4,000 did so in the month before that, said the Ministry of Health (MOH), which manages the programme through its volunteering arm SG Healthcare Corps.

Out of the 17,100 volunteers, 6,200 are healthcare professionals, including dentists, pharmacists and allied health professionals, MOH told The Straits Times.

They include those who have left or retired from the healthcare workforce, as well as those in private practice.

The other volunteers come from diverse backgrounds and include retirees as well as fresh graduates.

Volunteers who are found suitable are matched to healthcare institutions, trained and then deployed on the ground.

As Singapore ramps up Covid-19 testing, more than 3,000 volunteers have already been trained to perform swab tests at foreign worker dormitories and other community swab sites.

Among them are 300 dentists.

During the circuit breaker period in April, for example, 125 dentists and nurses, many from Q&M Dental, did a total of 13,000 swabs in three weeks.

Dr Ng Chin Siau, chief executive officer and founder of the dental group, said: "As dentists, we're very well trained in infection control and we have good hygiene standards in addition to our personal protection equipment, so we should give back to Singapore because we have the ability and means to do so."

Q&M dentists who received swab training have, in turn, trained other colleagues.

Close to 200 dentists - eight out of 10 across the group's 85 clinics - are now able to conduct Covid-19 nasal swabs.

Dr Mohan Rajah, an orthodontist, said: "Besides teaching one another to conduct the nasal swabs, practising on one another enables us to better understand what the patient goes through, so we know how to minimise their discomfort."

Q&M has spent at least $80,000 on personal protective equipment, including N99 face masks, hazmat suits, goggles and face shields, said Dr Ng.

On June 25, MOH said that Singapore plans to ramp up testing capacity from 13,000 to up to 40,000 as the economy continues to reopen gradually and more activities are allowed.