Guinea has announced an outbreak of the deadly Ebola epidemic after second laboratory tests on samples from victims came back positive for the virus.
The confirmation on Sunday comes a day after the government announced four fatalities among people who exhibited Ebola-like symptoms.
The Guinean Ministry of Health said that as of Sunday a total of seven cases have been confirmed, including the fatalities.
"Faced with this situation and in application of the international health regulations (IHR), the Guinean government declares an epidemic of Ebola virus disease in the prefectcure of N'zerekore, sub-prefecture of Gouecke," Minister of Health's Remy Lamah said in a statement issued late Sunday afternoon.
A crisis meeting convened by the government and its partners agreed on the imposition of safety measures that include isolation of all suspected cases, deployment of an emergency investigation mission in the affected region and activation of the intersectoral coordination through the One Health Platform.
The government is also accelerating a process of procurement of Ebola vaccines from the World Health Organization (WHO), the statement added.
According to Guinean authorities, the index case of the outbreak is a nurse who died at the end of January and was buried on February 1. People who attended the burial later exhibited Ebola-like symptoms, prompting an investigation.
Initial tests were carried out in Gueckedou, while the second tests were done in the capital, Conakry.
All the cases were recorded in the sub-prefecture of Goueke in the N'zerekore region, which is close to the border with Liberia and Cote d'Ivoire.
The development means that Ebola has returned to West Africa four years after the world's largest outbreak of the haemorrhagic viral disease ended there.
The 2014-2016 West African epidemic also began in Guinea, and then spread to its neighbours Liberia and Sierra Leone, infecting about 30,000 people and claiming more than 11,000 lives.
That experience has left Sierra Leone and Liberian authorities anxious over the outbreak in Guinea.
The 2014 epidemic affected 10 countries worldwide, the three Mano River Union neighbours - Guinea, Liberia and Sierra Leone - were highly affected due to their poor healthcare systems.
The Sierra Leone government on Sunday said it would do everything to prevent a spillover this time round.
The Ministry of Health activated its emergency response system and raised its alert level to II [Enhanced Surveillance, Active Case Finding and robust community Engagement].
In a statement, Health Minister Dr Austin Demby said even though there were no reported cases of the disease in the country, President Julius Maada Bio deemed it appropriate to take "prudent action to prevent any introduction of Ebola into the country and to institute measures to protect the lives of Sierra Leoneans."
The border between Sierra Leone and Guinea is current closed because of a land dispute between the two countries. But the Sierra Leone health authorities said they will heighten surveillance and improve on preparedness measures by collaborating with their Guinean counterparts.
"We intend to work very closely with our Guinean counterparts to quickly contain the situation," the Health Minister said in the statement.
The Liberian government also said it had ordered its Health ministry to institute surveillance and mount public sensitisation to ensure adherence to infection prevention control measures, while it works towards preventing a spillover.
The three countries had barely recovered from the effect of the 2014-2016 Ebola epidemic when the Covid-19 pandemic struck, reversing what little gains they had made.
The region is currently going through the second wave of the Covid-19 pandemic.