TORONTO - With fears that Canada could be hit by a massive wave of H1N1 influenza cases this fall, nurses across the country are preparing to take their places on the front lines of the pandemic - and bracing for the worst.

For months, provincial and territorial nurses groups have been engaged in pandemic planning with hospitals and government, while readying their members for a possible onslaught of cases that could swamp the system.

One of the greatest concerns is that there simply will not be enough nurses to handle a sustained influx of patients, especially those admitted with life-threatening complications.

While most cases of H1N1 so far have caused only mild symptoms, a proportion of those infected have become seriously ill, ending up in intensive care units on ventilators, often for weeks.

"If I was to look at the biggest threat, I think it's the lack of us having the capacity for the surge or the need for RNs on the front lines," says Linda Haslam-Stroud, president of the Ontario Nurses' Association.

There is already a shortage of nurses in the health-care system, she says. If swine flu does hit with a vengeance, it's likely some health-care workers will be among those who contract the infection.

"So we're in a situation where these nurses are not going to have enough colleagues to care for patients."

Sandi Mowat, president of the Manitoba Nurses Union, says Winnipeg hospitals have already experienced a sudden flood of swine flu patients needing specialized treatment.

In June, the virus swept through several northeastern aboriginal communities, leaving a trail of infectious destruction that saw dozens of patients airlifted to three Winnipeg hospitals.

"We had like a six-week surge in this province of very sick, high-acuity patients requiring ventilator care," she recalls. "Our ICU bed counts were at a maximum. We were actually over what our normal city ICU bed counts would be."

"And the end result was we didn't have nursing staff for those beds," says Mowat, adding that hospitals had to transfer RNs with previous ICU experience from other departments to help ease the shortfall.

Beyond adequate staffing levels, nurses are adamant that their working environments be as safe as possible - with appropriate protective gear like properly fitted N95 masks - and that they be kept informed by daily communication with hospital administrators.

They don't want a repeat of what happened during the 2003 SARS outbreak that killed 44 people in the Toronto area.

"SARS is still in the forefront of the nurses' minds across Ontario, obviously," says Haslam-Stroud. "Although it might seem like a long time ago to the public, it isn't a long time ago to the nurses who were in the trenches. We had two of our nurses die of SARS."

"I think the difference now is that nurses are very clear in saying they want to be on the front lines - that's what they're trained to do - but they are not willing to put themselves at risk like they did during SARS."

Among them is Kim Campbell, who contracted SARS during a second wave of the epidemic that struck Toronto's North York General Hospital after the province prematurely declared the threat had been contained.

Like other nurses stricken by severe acute respiratory syndrome, Campbell is still dealing with the physical and cognitive scars left by the disease, which put her in hospital for a week and required lengthy rehabilitation.

While back to full-time hours now, the mother of three continues to experience fatigue, has painful joint problems and becomes short of breath with any exertion. Her memory has also been impaired.

The emergence of the new H1N1 flu strain in April rekindled the anger and fear she felt over SARS and thought she had put behind her.

"They kept talking about it more and talking about the pandemic and what level it was. I got really scared."

"I went to my boss and I said, 'I just want to tell you if it gets worse, if it gets to the point where we're masked and gowned, I can't do it.' ... I just said to her I can't work."

"And I was almost crying because I thought 'I cannot put myself and my family through that again."'

Still, it's evident that hospitals, public health agencies and governments are determined not to be caught flat-footed with swine flu, as they were with SARS.

"I think now the nurses feel more secure," says Carolyn Edgar, the union rep for ONA members at North York General.

"There has been a concentrated effort on mask fit-testing and on personal protective equipment. If you go back to SARS, we didn't have this. So the difference between now and then is very significant. We're much more aware."

Like other hospitals across the country, her facility has ramped up infection-control measures for the public, including signs encouraging proper and frequent handwashing, widely available dispensers of hand sanitizer and a phone message instructing callers on what to do if they suspect they have the virus.

Open forums are being held to keep staff up to date and to address their concerns, she says.

Haslam-Stroud says nurses have more trust in government and their hospital employers because there's clearly been an emphasis on pandemic planning - a lesson driven home by SARS.

"But they know that it's still not enough, so they're going to be very wary and they're going to ask a lot of questions and they're going to be proactive where maybe we weren't that way previously."

Mowat's union recently delivered a set of recommendations to the Manitoba government on preparing for a predicted upsurge in swine flu cases in the coming months.

The document says the government should be surveying RNs across the province to locate former ICU nurses who could volunteer to work if flu cases overwhelm available hospital staff.

Mowat says Manitoba nurses are fortunate in one respect - the province has given assurances that all health providers will get a properly fitted N95 mask, which she calls the most effective means of preventing transmission.

"I think that's the one thing nurses across Canada need to be demanding," she says. "We should have the best possible protection and we don't care what they say is adequate, we want what is best."

"At the end of the day, we have to protect ourselves and we have to protect our families - because it's all one circle. If the nurse gets sick, then the nurse can't go to work to take care of patients. It's as simple as that."