The European Commission (the EU’s executive branch) has approved a functional Ebola vaccine, Ervbo, for human use. This is the first treatment of its kind to ever show efficacy in humans.

In an announcement on November 11, the European Commission granted Merck Sharp and Dohme B.V. marketing authorization for Ervebo in Europe. The European Medicines Agency, EMA, first recommended approval of the vaccine in October this year. A functional Ebola vaccine meant for human use has been a goal of the global research community ever since the massive outbreak in West Africa between 2014 and 2016.

A world first

This is the first time a vaccine for the disease that works in humans has been introduced for the dreadful disease. The Ebola virus can cause severe hemorrhagic fever, which involves both a rise in body temperature and massive internal bleeding from blood vessels throughout the body. The virus firsts attacks immune cells, which impairs our body’s early defenses. Eventually, macrophages do start striking back, but as they digest the virus, the cells release proteins that lead to the formation of small blood clots and inflammation, and cause leaks in your blood vessels. This is a very severe process that leads to a patient’s internal organs being starved for oxygen — around 90% of those infected by the virus die in this stage, according to the World Health Organization (WHO) Africa Region Office.

Until now, the only real way to protect yourself against Ebola was to avoid being contaminated — which is obviously hard in a full-blown outbreak. The only thing close to a functional vaccine for humans was a vaccine that worked in macaques, developed by researchers at the Public Health Agency of Canada’s National Microbiology Laboratory.

The new vaccine works by exposing patients to a form of the virus that can’t cause an infection. Our bodies can thus interact with the pathogen and learn how to fight it when the real virus comes around. It has been tested in an attempt to control Ebola outbreaks in the Democratic Republic of the Congo (DRC), showing great promise: the vaccine had an estimated protective efficacy of 97.5% in field studies. That’s a remarkable result in the best of conditions, and especially in the volatile conditions in the DRC, which is still struggling to recover from a series of civil wars.

Now that the European Commission has stamped its approval on the vaccine, there is a lot of interest that other regulatory bodies follow suit. The Food and Drug Administration (FDA) in the US is currently reviewing the vaccine for approval and could give the green light sometime in early 2020. However, Merck doesn’t expect the vaccine to make a lot of money: vaccines are, traditionally, not very lucrative, and Ebola is most prominent in poorer countries. The global health community might need to step in and support (i.e. fund) the use of the vaccine for it to reach as many of the people that need it as possible.