A new report by Save the Children suggests that at least 180 Congolese children have lost both parents or caregivers since the outbreak began.

This outbreak is now the deadliest in DR Congo's history and the second-worst ever - only surpassed by the 2014-2016 West Africa outbreak when more than 11,000 people died.

Experts say that it may have been spreading in DR Congo since as early as February but the infections of the Bundibugyo species were initially misdiagnosed as typhoid and malaria.

This, along with the difficulties health teams have in working in conflict-hit areas, local suspicions of health authorities and some traditional practices around burial, have hampered the response.

It is hoped that the Ervebo vaccine may be able to help.

The WHO confirmed that 20,000 doses would be used in a clinical trial to assess the vaccine's effectiveness against Bundibugyo, while 50,000 doses will be administered to front-line health workers.

The WHO and the Africa Centres for Disease Control and Prevention welcomed the allocation, describing it as a vital reinforcement of the response.