This vaccine is about two years old so nothing at all is a known about its long-term effects, so the repeated claims on the WHO citation that it is "proven safe and effective" show you something Not very complementary about their definition of "proven safe".
There appears to be no evidence whatsoever that the vaccine was instrumental in curbing spread. There have been at least 10 outbreaks previously with no vaccine that they stopped so it seems quite plausible that the strategy of isolating victims is what is being successful, just as it was in smallpox. At best this seems another case of post hoc ergo propter hock.
The current outbreak, in spite of the vaccine, has spread to urban centers and is sometimes described as out of control. https://www.doctorswithoutborders.org/what-we-do/news-stories/story/drc-what-we-know-about-latest-ebola-outbreak?source=ADD180U0U00&utm_source=AdWords&utm_medium=ppc&utm_campaign=GooglePaid&utm_content=NonBrand&gclid=EAIaIQobChMItJz6yc7R3gIVg-DICh3-5g-HEAAYASAAEgL-6fD_BwE
I haven't found any evidence or claim that the vaccine is even effective against the current strain. It is claimed to be effective against one strain, but nobody seems to be claiming that is the current strain.
Ebola is an animal disease that has probably existed for a very long time although the first case that was confirmed was in 1976. In history there are less than 2000 deaths confirmed from Ebola, In spite of the fact that the vaccine was only very recently developed and hasn't even been licensed yet. Only some thousands of people have ever been vaccinated. To try to compare this to all the deaths from the smallpox vaccine and all the ongoing deaths likely happening from vaccine aluminum and all the deaths from RSV which was presumably due to contaminated polio vaccine and all the autism which is likely due to vaccine aluminum http://truthsift.com/search_view?topic=&id=406&next=6678&fs=0 etc Is extraordinarily alarmist about Ebola and not supported by the evidence. It seems a very thin reed indeed to try to hang the benefits of vaccines on a vaccine that isn't even licensed yet.
The question in this topic is whether there is strong evidence that vaccine benefits outweigh the harm. This could not be described as strong evidence of that.