Liberia’s Deputy health minister Tolbert Nyenswah said tests confirmed that the 17-year-old man, from a town near the main airport, had died of the disease. Officials are investigating how he contracted Ebola, Mr Nyenswah said.

liberiaThe boy got sick on Jun 21, and he died on Jun 28 at his home in the Margibi County village of Nedowein. The remote village is about 30 miles south of Monrovia, not far from its international airport.

Liberia was declared free of Ebola six weeks ago, following the deadliest outbreak in the disease’s history.

Earlier this month,  Peter Graaff, Acting Special Representative and Head of the United Nations Mission for Ebola Emergency Response (UNMEER) said, “With Liberia we have reached a milestone. This is exciting progress, and certainly we congratulate Liberia on its hard work, but we cannot forget that the country remains at risk.”

More than 11,000 people have died of the disease since December 2013, the vast majority of them in Liberia, Guinea and Sierra Leone.

The countries had largely curbed the spread of the disease – but the number of new cases has risen recently, with the start of the rainy season in West Africa.