The Canterbury District Health Board says damp and unchanged personal protective equipment (PPE) was likely to blame for three of its healthcare workers getting Covid-19.
The staff tested positive for the virus last week, after caring for the coronavirus patients from Rosewood Rest Home and Hospital, and helping move some of them to Burwood Hospital in Christchurch.
Technical experts from the health board had been investigating how the staff became unwell, and today the health board said a "PPE breach" was the most likely scenario.
Incident controller Dr Sue Nightingale said that on April 6, when the patients were transferred, some staff were unable to change PPE as frequently as recommended.
"It appears that due to the demands on staff, in particular on the day of resident transfer from Rosewood to Burwood and the day after, it was not always easy for them to interrupt care for very unwell dependent patients," she said.
"Some staff reported their PPE had become moist with the physical exertion that occurred over some hours that day. This factor is likely to have led to exposure to Covid-19."
At that time, RNZ understands staff had access only to paper masks, rather than the full-filter N95 masks. The health board moved to provide them with the N95 masks and visors more than a week later, on April 15.
The health board says staff caring for Rosewood residents now change their PPE at least every two hours, and a buddy system has been introduced to ensure they use PPE correctly.
But the Nurses Organisation said that should have happened sooner because staff had already been asking for better PPE by the time they moved patients to Burwood Hospital, citing shortages of supplies, and gowns that ripped.
The union kaiwhakahaere (organiser), Kerri Nuku, said it was unfair for the health board to effectively point the finger at employees.
"It's unfair to lay the blame on the nursing staff not changing regularly when there actually wasn't stock available, or quality stock to make them feel comfortable and be safe at work," she said.
"I appreciate that this is still under investigation but employers have an obligation under the Health and Safety at Work Act to ensure that all staff - when you're dealing with a situation needing PPE gear - are kept safe."
Nuku said PPE availability had improved across the country over the past four weeks, but it was important to ensure that "steady supply" continued.
"We need to make sure that we've got PPE to deal with Covid-19, should we have cluster outbreaks, but we also need to make sure that we've got supplies to cope with winter ailments."
