Liberia, which had been Ebola-free for more than a month, reported a new case of the virus Tuesday.
The body of a 17-year-old boy tested positive for Ebola in Margibi County and authorities have begun tracing people the victim may have come into contact with while infected, Deputy Health Minister Tolbert Nyenswah said on Tuesday.
"There is no need to panic. The corpse has been buried and our contact tracing has started work," Nyenswah told Reuters. Margibi is a rural area close to the capital Monrovia, and is home to the country's main international airport.
At least 11,207 people have died from Ebola in Liberia, neighboring Guinea and Sierra Leone since the outbreak began in December 2013, World Health Organization (WHO) spokesman Tarik Jasarevic told a news conference in Geneva. More than 27,000 have been infected.
Around 43 percent of the deaths were in Liberia, where the world's worst outbreak of the disease peaked between last August and October with hundreds of cases a week.
The epidemic has tapered this year, with 12 new confirmed cases reported in Guinea and eight in Sierra Leone in the week to June 21, according to WHO figures. Even so, health officials urge vigilance to prevent a resurgence. As long as cases mysteriously pop up, health experts fear the virus is still circulating unseen.
The new case will test Liberia's response capacity at a time when international health organizations have wound down their presence in the affected countries, said Fatoumata Lejeune-Kaba, spokeswoman for the U.N. Ebola response mission.
Liberia fought Ebola at a community level, adopting regular hand-washing and the safe burial of bodies among other measures and the discovery of the new case shows that systems for testing remain in place, she said.
"This should have been expected because as long as there is Ebola in the region no one country can be safe. Liberia is vulnerable because of Guinea and Sierra Leone,” Lejeune-Kaba said.