Geneva (AFP) - No new Ebola cases were confirmed last week, marking the first full week without fresh cases of the deadly disease in a year an a half, the World Health Organization said Wednesday.
"No confirmed cases of Ebola virus disease were reported in the week to 4 October," WHO said in its latest situation report on the west African Ebola outbreak.
"This is the first time that a complete epidemiological week has elapsed with zero confirmed cases since March 2014," it said.
The deadliest-ever Ebola outbreak since the virus was identified in central Africa in 1976 has killed 11,312 of the 28,457 people infected since December of 2013, according to the latest WHO figures.
Nearly all the victims have been in Guinea, Liberia and Sierra Leone.
Liberia was declared free of Ebola transmission in early September, and Sierra Leone in late September began a 42-day countdown to becoming Ebola free.
WHO said Wednesday that the epidemic had clearly entered a third phase and that the focus was on driving "case incidence to zero, and ensure a sustained end to (Ebola) transmission."
The UN health agency said that all contacts had been completely followed up in Sierra Leone, which has seen no new cases for the past three weeks.
But the danger is still not over.
WHO warned that two high-risk contacts in Sierra Leone, one from Bombali and one from Kambia, had gone missing.
"Efforts to trace these missing contacts and mitigate the risk of any undetected transmission will continue until at least 42 days have elapsed since the last reported case in each district," WHO said.
In Guinea, meanwhile, over 500 contacts remained under follow-up in three of the country's prefectures, it said, stressing though that all the contacts were associated with a single chain of transmission centred on the Ratoma area of the capital, Conakry.
Another 290 contacts had been identified but had not been traceable for the past 42 days.
The four latest cases in Guinea, reported on September 26 and 27 in Forecaria, were people infected by an unregistered contact, likely linked to the Ratoma transmission chain, WHO said.