The West African country is confirmed free of Ebola transmissions and enters a period of 90 days of surveillance.
The Ebola outbreak in Sierra Leone where British nurse Pauline Cafferkey caught the disease has been declared over as a crucial milestone is reached.
It has been confirmed that 42 days has elapsed since the last new case of the deadly virus – the period of time that must pass for a country to be deemed Ebola-free.
Ms Cafferkey contracted the disease after treating patients in Sierra Leone at the height of the outbreak.
Following her initial recovery, she is being treated in hospital after falling ill again with meningitis, caused by a re-emergence of the virus.
Sierra Leone being declared free of the disease will be a huge relief according to Dr Tumba Junior, a doctor with the charity GOAL based at its treatment centre in Port Loko.
“Everyone is celebrating but we have to keep in mind that we must be careful,” he said.
“We could still have positive cases after this period.”
It is 18 months since the outbreak began in West Africa, killing more than 11,000 of the 28,500 people known to have been infected.
It claimed nearly 4,000 lives in Sierra Leone.
In a statement, Dr Anders Nordström, the World Health Organisation representative in Sierra Leone said the news was a significant milestone in the fight against Ebola and praised the “tremendous hard work and commitment” of those involved in the fight.
“We now have a unique opportunity to support Sierra Leone to build a strong and resilient public health system ready to detect and respond to the next outbreak of disease, or any other public health threat,” he said.
“The power of the people of Sierra Leone is the reason why we could put an end to this outbreak today.”
The fear of Ebola has left communities living under a cloud of anxiety and mistrust, unsure where the virus would strike next.
Liberia was declared free of Ebola in September but Guinea is still seeing some new cases.
On the border with Sierra Leone, no chances are being taken and health checks at the crossing in Kambia are mandatory.
Otim Patrick, field co-ordinator for the World Health Organisation at the site, said it is crucial not to “let your guard down”.
“You can have a case and it takes you back to zero,” he said.
“For a district like Kambia, which is at the border with Guinea, and with Guinea still having active transmission… they just had a case reported a day ago.
“It’s important that we maintain the level of vigilance so that complacency does not take us back to square one.”
At its worst hundreds of new cases were reported every week across West Africa.
Those caring for the sick left no part of their body uncovered if given the chance but too often the vital protection was not available.
The outbreak has fuelled medical advances that have seen new vaccines and drugs being developed.
But for many of the 17,000 survivors there are health complications to deal with.
Head nurse Isatu Mansaray at the Port Loko centre said: “So many of them complain of deafness.
“So many of them complain of joint pains… so much being stigmatised by the community so we really need psycho-social therapies.
“So many have lost many members of their family, like 10 or 15 members of the family.”
For the next 90 days, Sierra Leone will be under a heightened state of surveillance to make sure the virus is gone for good.
Its people have survived civil war in the country and now Ebola too.
If there is a next time, Sierra Leone will be far better prepared.
Its people are just hoping it never comes to that.