Burundi has started vaccinating its health workers against Ebola, the World Health Organization (WHO) has said.
Those at the Gatumba border near the Democratic Republic of Congo, where a year-long Ebola epidemic has killed at least 1,800 people, are the first in line for the vaccinations overseen by the WHO and Burundi's health ministry.
The health workers are being vaccinated with rVSV-ZEBOV, an unlicensed product.
"Although this vaccine is not yet approved and its commercial use is not yet authorised, it has been shown to be effective and safe during Ebola outbreaks in West Africa," the WHO statement said.
The vaccine, developed by US pharmaceutical group Merck, proved "highly effective" in a trial conducted in Guinea in 2015, WHO representative in Burundi Dr Kazadi Mulombo said.
"The vaccination of health and front-line staff is a significant step forward in preparing for the response to this disease," he added.
Burundi has not recorded any cases of Ebola so far, but its border with DR Congo is considered highly porous, and the whole region is on high alert.
Uganda started its largest-ever trial of a second experimental Ebola vaccine, being developed by another US drug maker, last week, the Reuters news agency says.
Earlier this week, scientists announced a breakthrough with a trial in DR Congo of two drugs that were able to cure 90% of patients infected with Ebola./BBC news