Rwandan health authorities will begin a vaccine study against the Marburg hemorrhagic fever as the East African country tries to stop the spread of an outbreak that has killed 12 people.

Eleven people have died in Rwanda as the African country continues to fight an outbreak of Marburg virus. The Rwandan government said there were 36 confirmed cases of the virus in its latest update, with 25 people in isolation.

For the first time in Rwanda’s history, its health ministry is dealing with an outbreak of Marburg virus disease, a rare but deadly hemorrhagic disease similar to Ebola – but unlike Ebola, there is no treatment or vaccines for Marburg,