Since then, faith leaders have worked together to deliver health messages about how to stay safe and bury bodies without being at risk of infection.
But some say that clerics should have been involved far sooner in the crisis.
According to a senior member of the Ebola Task Force in Kenema District in Sierra Leone, the country "would have saved more lives and more money had religious leaders been engaged at an earlier stage of the disease outbreak."
Revd Jonathan Titus Williams, from the Evangelical Fellowship of Sierre Leone, told Premier that Ebola cases are declining and people are slowly trying to move on: "We have orphans, we have widows that have been left, we have people that have been affected by the Ebola virus.
"So we see that there's still a lot to do, some people lost their jobs, some people lost their homes, some people lost their properties."
"They need to rebuild their lives again and I also want them to really pray for God to continue to bless these people... and all those that have sacrificed their lives, time and money to help fight Ebola in Sierre Leone."
'Keeping the Faith', a joint report by CAFOD, Christian Aid, Tearfund and Islamic Relief, explains how different faith leaders delivered health information that people trusted, and acted as spokespersons in areas the government and NGOs could not reach.
It has been reported that they dismissed rumours about the disease and encouraged communities to accept life-saving advice from health workers.
They are also playing a vital part in counselling survivors and challenging stigmas.
CAFOD Director, Chris Bain, said: "In Sierra Leone and Liberia, priests and imams have shared the same health messages as the government and health workers, but because they are often closer to the people their messages were listened to and accepted.
"It is vital that we learn lessons from the delay in involving them. In many parts of the world, local churches and mosques are the first places people turn to when disaster strikes - and the international humanitarian system is simply not good enough at working with them."
Imran Madden, Head of the Humanitarian Department at Islamic Relief Worldwide, said: "Many of those who led the fight against Ebola were faith leaders, Christians and Muslims, who rose to the challenge of their generation.
"Building on the deep-rooted trust placed in them by the community, they went door to door, village to village to give messages on behaviour change.
"Their engagement marked the turning point in the fight against this terrible disease and this research explores their role and the many lessons we can learn for future disaster responses."
Leslie Scott, the World Vision Sierra Leone National Director, said: "We are extremely proud of our community partners in the districts we work in across Sierra Leone: the parents, teachers, paramount chiefs, faith leaders and government officials. Together, we have successfully helped to achieve and maintain zero new cases of Ebola for months now.
"We are winning the war on Ebola, but it's not over yet. It only takes one case to reignite the outbreak, so there is no room for complacency. We need sustained international support not only to beat Ebola in Sierra Leone, but to transform national systems and structures across West Africa, so that we can avert future outbreaks," he explained.
Listen to Premier's Hannah Tooley speak to Revd Jonathan Titus Williams here: