The world finally has an Ebola vaccine. On 11 November, European regulators approved a vaccine that has already helped to control deadly outbreaks of the virus — the first time any immunization against Ebola has passed this hurdle.
The decision by the European Medicines Agency (EMA) to allow US pharmaceutical company Merck to market its vaccine means that the product can now be stockpiled and, potentially, distributed more widely than it is now, particularly in Africa. In 2015, Gavi, the Vaccine Alliance — a global health partnership based in Geneva, Switzerland, that funds vaccine distribution in low-income countries — told Ebola-vaccine manufacturers that it would commit to purchasing their immunizations once they had been approved by a “stringent health authority”, such as the EMA.
Although several other vaccines against Ebola — a haemorrhagic fever that causes severe diarrhoea, vomiting and bleeding — are in development, Merck’s is the only one that has been tested during an outbreak, in which it was shown to be highly effective at preventing infection.
The vaccine, first patented in 2003, has been administered on an emergency basis to quell the ongoing outbreak in the Democratic Republic of the Congo (DRC), which has killed some 2,000 people since it started last year. It was also used during another 2018 outbreak in that country, and in Guinea in 2015. In the current DRC outbreak, hundreds of thousands of people have received the Merck shot, including more than 60,000 health-care workers in the DRC and several neighbouring countries.
“This is a vaccine with huge potential,” said Seth Berkley, chief executive of Gavi, in a press release after the EMA’s decision. “It has already been used to protect more than 250,000 people in the DRC and could well make major Ebola outbreaks a thing of the past.” The organization has supported the stockpiling and delivery of Ebola vaccines and hopes to build up a global supply that could be rolled out quickly during future outbreaks.
The EMA’s approval “makes a big difference”, says David Heymann, an epidemiologist at the London School of Hygiene and Tropical Medicine. But he stresses that research into the Merck vaccine and development of others must continue. “The message is that the research is not done. It must continue,” he adds. “It’s really important to continue to study vaccines and develop those second- and third-generation vaccines.” These could offer longer-lasting immunity, target more than one species of Ebola and be easier to store….
