There were 381 active infections in Victorian healthcare workers announced on Sunday – an extra 81 since Friday. And that figure doesn’t include the hundreds of healthcare workers now furloughed while awaiting test results after being in close contact with a known case.

The infections have been fuelled by inconsistent training in use of personal protective equipment, amid a lack of transparency surrounding how the virus is being acquired and spread throughout workplaces such as hospitals and aged care homes, doctors say.

The head of the Australian Hospitals and Healthcare Association, Alison Verhoeven, says the pressures on hospitals and healthcare workers as they deal with the second wave of Covid-19 “has been immense”.

“Without strong community cooperation, our health services will be overwhelmed and the risks faced by healthcare workers will be even greater,” Verhoeven says. People need to adhere to public health directives to wear a mask, get tested and stay at home, she says, or health workers in the community risk being infected.

But while many health workers are being infected in the community, health districts are grappling with workplace-acquired infections and exposures. The state government has repeatedly refused to answer questions about how many healthcare workers acquired the virus in the workplace, and what the source of infection in those workplaces was.

Verhoeven says inconsistent protocols and training about the use of personal protective equipment is a part of the problem. While additional protective equipment is being made available across the system, “this effort needs to continue to be stepped up, particularly providing access to P2 masks for healthcare workers who are working with potentially Covid-positive or asymptomatic patients”, she says.

“Training may differ across not only health districts and hospitals, but also in general practice and across aged care and disability services. Prioritising access to PPE and infection control training, and ensuring this is available to any worker who potentially will be in contact with Covid-positive or asymptomatic patients is critical. But the best of training won’t be of assistance where appropriate PPE equipment is in short supply so focus also has to be on access to equipment including P2 masks where appropriate.”

On Sunday the Victorian premier, Daniel Andrews, acknowledged the gravity of the situation. “Whenever we have clinical staff and other critical health workers away, furloughed because they are a close contact or in fact as an active case, that does put some additional pressure on our system,” he said, telling reporters there had been 10 deaths overnight, and that there were 228 Victorians in hospital, 42 of them receiving intensive care.

Hundreds of health staff who had retired or who had taken a break from the field, including midwives, nurses and specialist health workers, were being called on and trained to fill the gap, he said. Australian defence force personnel are also being trained in driving ambulances and PPE protocol. Some 60 paramedics have been furloughed due to contracting or being exposed to the virus.

The head of the Victorian branch of the Australian Medical Association, Dr Julian Rait, says while some health services have embraced PPE training that is comprehensive and includes specially fitting masks to frontline workers, training in some hospitals has left a lot to be desired.

“I can tell you many health networks and services are behaving in an exemplary way to show people how to use PPE properly and they assist with fitting and testing,” he says. “But I was speaking to a doctor at one of the major hospitals who said to me, ‘We are just not getting the same level of training as a hospital like Monash.’”

He adds that because the virus is largely spread by droplets, people are underestimating aerosol spread and are slow to take in the growing evidence that it may contribute to spread more than previously appreciated. “So there is a little bit of a delay in people appreciating the changing advice around workplace health and safety,” he says.

While the state government has been outlining the locations and numbers of infections in aged care homes, it has stopped providing daily updates to the public about infections in hospitals. The government has only repeatedly said that most healthcare worker infections were acquired in the community, not the workplace. A senior doctor at one Melbourne hospital where dozens of staff are furloughed and at least a dozen staff had tested positive says that many staff feel there is a lack of transparency around the issue.

“The general feeling is that the emphasis on community acquisition seems to absolve the government of responsibility to make a leap of initiative and put additional measures in place,” she tells Guardian Australia. “What we know for certain is that we are seeing more patients with Covid, and we are more prepared than before in terms of resources and protocols, but with increasing numbers of staff getting sick or going into quarantine, we know that can change very quickly. Our A-team is currently on the frontline, and you don’t want to be subbing the less experienced players in the third quarter.”

A nurse working at the Royal Women’s hospital, where 11 staff have been infected, says: “I think most staff believe that the staff who have contracted the virus got it through exposure to other staff.

“The hospital does not reveal any of the circumstances or departments of the positive cases but I know of at least two who contracted it in training sessions.”

She adds that the Royal Women’s hospital and the Royal Melbourne hospital are moving to digital records in August, and there has been a huge precinct-wide push to train all staff face-to-face in the new system before then. “This has meant close quarters meetings with minimal contagion measures,” she says. “Obviously since the positive cases have emerged these sessions have been minimised but I think that’s where a lot of the infections took place.”

The head of the federal branch of the Australian Medical Association, Dr Tony Bartone, says more transparency is needed to understand how infections are occurring and to stop them. He says Victoria also lacks a central system for tracking the movement of casual healthcare workers who are employed across multiple health are settings. The office of the health minister, Jenny Mikakos, has stopped responding to questions from Guardian Australia about where staff were infected and about PPE training.

“We need to more easily understand who is working where and when so we can trace them,” Bartone says. “The real risk to the frontline of our hospitals at the moment isn’t beds, ventilators or intensive care unit spaces, it’s the numbers of doctors and nurses available to take care of patients. That’s the risk at the moment. And we need more transparency around what is happening to the workforce at that frontline.”

On Sunday Andrews acknowledged that a much larger discussion about casual workers across the health, aged care and other sectors would be needed once the pandemic ended. The causal and insecure work force “is a structural weakness in our economy that has been very graphically exposed” through the pandemic, he said. Many could not afford to take time off work while waiting for test results due to losing income and no access to sick leave, prompting the government last week to announce a $300 payment for those with no sick leave who were awaiting a test result.

“Insecure work is no good for public health in terms of dealing with a global pandemic … that is a real challenge, not just for public health, but a challenge for providing for your family, for stability – that is something we have to return to, not just as Victorians, but perhaps at a national level once this is over,” he said.

• Do you know more? melissa.davey@theguardian.com