Liberia said Wednesday a teenager who died of Ebola fever had spread the virus to at least two more people, confirming the first outbreak of the tropical disease for months.
Health officials told AFP the infected pair had been in physical contact with the 17-year-old victim before his death on Sunday in a village near the country's international airport, around an hour's drive southeast of Monrovia.
"One hundred and two contacts have been identified, although that number is expected to increase as investigations continue," the World Health Organization (WHO) said in its latest report on the epidemic.
"At this stage the origin of infection is not known. The case reportedly had no recent history of travel, contact with visitors from affected areas, or funeral attendance."
Cestus Tarpeh, a spokesman for the health department where the boy died, confirmed the two new patients had tested positive and said the authorities were awaiting the results of further blood tests on other contacts.
The news came a day after Health Minister Bernice Dahn announced the first Ebola infection in Liberia for more than three months, warning that it was "likely that we will find additional cases".
Authorities have warned that a herbalist who treated the boy had evaded the authorities and was on the run.
Moses Massaquoi, the head of the Liberian government's Ebola crisis management department, said 14 conventional health workers among the identified contacts had placed themselves in voluntary quarantine.
The new outbreak comes with the country still reeling from a nightmarish epidemic which wrecked its health service and economy and left 4,800 Liberians dead.
Before the new cases Liberia had reported its last victim on March 20 and was declared Ebola-free on May 9.
Neighbouring Guinea and Sierra Leone are both still battling the epidemic, which has killed more than 11,200 people in 18 months across west Africa.
US Assistant Secretary of State for African Affairs Linda Thomas-Greenfield told a news conference broadcast online from Washington that the new Ebola death was "a warning to us that the job is not done".
Residents in Monrovia, a crowded chaotic city of around one million people, spoke of their fears that the Margibi outbreak would develop into a full-blown epidemic.
"I am scared -- I am so scared that I don't even know where to start," said Jeneba Freeman, 45, a stallholder in the capital's Redlight market.
Ebola is spread among humans via the bodily fluids of recently deceased victims and people showing symptoms of the tropical fever, which include vomiting, diarrhoea and -- in the worst cases -- massive internal haemorrhaging and external bleeding.
Experts have speculated that the 17-year-old, who has not been named, could have been infected by an entirely new variant of the virus from an animal such as a fruit bat, rather than from a human.
A more worrying possibility is that clusters of Ebola continue to smoulder under the surface, far from the gaze of local or international health authorities.
"We heard on radio that Ebola has turned around to come back to Liberia," said Samanta Blamo, 55, another stallholder at the Redlight market, where buckets of chlorinated water began to appear on Wednesday.
"This is why we are bringing our Ebola buckets. We were still washing our hands but only few buckets were here. Now everybody has one again, just like the way it was in 2014."
During the months of peak transmission from August to November last year Liberia was the setting for some of the most shocking scenes from the outbreak, by far the worst in history.
The country was reporting more than 300 new cases a week, with uncollected and highly infectious bodies piling up in the streets of Monrovia.
The health system -- embryonic before the crisis, with some 50 doctors and 1,000 nurses for 4.3 million people -- was devastated, losing 192 health workers out of 378 infected.
Schools remained shut after the summer holidays, unemployment soared as the formal and black-market economies collapsed and clinics closed as staff died and non-emergency healthcare ground to a halt.
Parents found themselves on Wednesday mulling the dilemma of whether to curtail the end of an already hugely disrupted school year by keeping their children at home.
Patricia Sleboh, a mother-of-three, told AFP she would rather keep her children from classes than risk "losing them to Ebola".