The head of the Irish Nurses and Midwives Organisation (INMO) has said some members have been turned away while queueing for the coronavirus vaccine.
Phil Ní Sheaghdha has also raised serious concerns about burnout among doctors and nurses.
She told Pat Kenny: "I think that the exposure to the high death rate, the fear of attending work - but attending anyway - and the fear of bringing this horrible virus home - that is a constant with nurses and midwives, and other healthcare workers".
"That hasn't gone away, that's been a constant - and there is no escape".
"They have stepped up and they have met the virus head on; but what they're saying is that has taken a personal toll.
"Many of them have expressed very real fears - nightmares, inability to sleep - and those that have been infected then... they have had quite bad experience.
"Some have been very ill and some have not recovered".
She said there is "a lot of work to do" with authorities to ensure services are available for the workforce.
Vaccine roll-out
A HSE portal opens on Tuesday for healthcare workers to apply to be vaccinated.
But Ms Ní Sheaghdha said members have been frustrated over its roll-out.
"We set up a freephone helpline for our members at the beginning of this pandemic, and we had to re-open it again when the vaccine roll-out commenced.
"The manner in which the vaccine roll-out transpired, they felt very, very strongly was haphazard because some were waiting in a queue and were turned away on the basis that the vaccine had run out.
"Others were told 'You're scheduled for your vaccine tomorrow', and then got a phone call to say 'No, we haven't got the delivery.
"Others were told the vaccine had been diverted to a different work location, and others saw non-frontline healthcare workers being vaccinated ahead of them.
She described this as "the end of the tether" for them.
Asymptomatic infections
Ms Ní Sheaghdha is appearing before the Oireachtas Joint Committee on Health on the effects of the pandemic on healthcare workers.
On this, she said: "Obviously the main concern is the high rate of infection among healthcare workers, the single occupation group amongst that high figure are nurses and midwives."
She said the majority of these are women.
"That hasn't abated, we still have a very high, a higher than acceptable level of infection, and we believe one of the main issues that needs to be addressed is serial testing in acute hospital - which doesn't exist currently".
She quoted a HSE study from two hospitals, which found that the level of asymptomatic presentation by health workers was "quite high".
"You can't treat and you can't deal with what you don't know exists - so testing is imperative, we've been looking for this since last April".
"It's just incredible to us that routine testing of healthcare workers in acute hospitals still doesn't exist".
She said the Health and Safety Authority (SHA) should be inspecting outbreaks or clusters in hospital settings "in order to look at the environment, to look at all of the possible causes, so that the maximum protection can be afforded to the worker".
She said the union remains critical of a recruitment freeze.
"This is a legacy of our recruitment practices in the public health service."
"I think one big lesson from all of this has to be that we can never again tolerate or introduce a moratorium on the recruitment of nurses or midwives".
