"But then it took off like wildfire in the four weeks we were there," Ms Collins said.
With improved education and early health care, the death toll that initially saw up to 75 per cent of victims die came down to about 50 per cent.
The Red Cross Ebola Treatment Centre, about 18 km out of Kenema, was built in a matter of weeks on land shaved out of the jungle. When it was ready, the Red Cross medical and aid teams carried out a "slow response", in which every process is measured, planned and part of a rigorous process rather than "fighting fire with fire".
The international team was responsible for every aspect of developing and running the facility, including sourcing supplies -- such as scrubs and gumboots -- and training workers.
"You're never just a nurse," Ms Collins said.
The Kenema treatment centre was considered a five-star facility "because we had piped chlorine".
Its isolation from town meant most patients were ambulanced there, helping control the rate at which cases arrived and could be helped. With no vaccination yet available, care was based on treating other illnesses the patient had, nutrition, worming, hygiene and combating the extremely high fever that comes with the virus.
At the same time the Red Cross and associated groups built the treatment centre, they developed a triage facility outside the Kenema Government Hospital to catch patients presenting with ebola.
"In triage we had a 1.5-metre high wire fence between us and the patients. You could tell straight away if someone had ebola. We could stop them entering the general hospital and get them to our centre."
Ms Collins returned to work as a midwife and nurse at Whangarei Hospital on Wednesday after spending 21 days in quarantine.
"Given the chance, I'd do it all over again," she said of her experience.
Ms Collins was at the same centre where Australian nurse Sue-Ellen Kovack, 57 worked. Ms Kovack sparked an Ebola scare when she went to Cairns Hospital with a raised temperature just days after returning from Sierra Leone. However, she was cleared of having the virus today.
Their deployment was prompted by a request to the International Federation of Red Cross and Red Crescent Societies by the Government of Sierra Leone and the World Health Organisation (WHO).
The outbreak has killed more than 3800 people, according to the latest World Health Organisation figures.
The vast majority of those deaths have been in Guinea, Liberia and Sierra Leone.
