Ms Collins, a midwife and women's health nurse at Whangarei Hospital, and Ms Mackie, a Wellington nurse and health co-ordinator, were the only New Zealanders in the team, and were responsible for setting up and operating the treatment centre on a site shaved out of jungle.
When the pair touched down in Sierra Leone, the death rate was about 70 per cent. But they were not deterred. In fact, they asked to extended their stay, saying "we still had a job to do".
"While we were there we were so heads-down-and-bum-up we missed a lot of the news that the rest of the world was getting. We weren't influenced by fear or misinformation or politics," Ms Collins said.
The international team was responsible for developing and running the treatment centre. But closed borders made it difficult to get supplies.
Often Ms Collins, armed with "fistfuls of cash", scoured Kenema, 18km away, for gumboots, scrubs and other equipment.
Ms Mackie wrote a blog that was published on the Red Cross website about her experience.
"Wearing PPE or personal protection equipment is like doing your job wearing your own personal sauna. Not a single piece of skin is exposed. You wear scrubs underneath yellow overalls, a plastic apron, face mask, hood protection, goggles, two pairs of gloves and gumboots which are wet from soaking in chlorine.
"You spend 45 minutes maximum in the isolation unit assessing patients, giving medications, assisting with feeding, hygiene and also declaring the deceased.
"The idea is to go into the isolation unit a maximum of four times per shift. It is very hot work and you are drenched with sweat at the end and need a recovery and rehydration period.
"We had some heartbreaking moments and other amazing survival stories."
