The European Commission has approved the first Ebola vaccine for official use. Until now, vaccination has been carried out as part of a charity-testing operation, this is actually a clinical trial in the field. The vaccine has now been granted the status of a permitted drug, which means that its manufacturer, Merck, will be able to deliver it more easily and faster to African countries.
The largest Ebola outbreak began in West Africa in 2014. In many countries, it has come to nought since 2016, but in the Democratic Republic of the Congo, the epidemic continues today. According to the European Commission, some 3,000 people in the Congo have been infected, with a mortality rate of about 67%. WHO assigned the outbreak as an international emergency in July 2019 and extended the status for another three months in October.
Until now, there has been no official vaccine for ebola virus. Despite the fact that their development began in 2014, all of them were considered experimental. Now eight vaccines are in different stages of the study, and one of them – the Ervebo vaccine (Ervebo, rVSV-EBOV-GP) from Merck – has finally received official recognition. It is based on the vesicular stomatitis virus, which affects livestock but is harmless to humans. The modified virus, in addition to its own genes, carries information about one of the proteins of ebolavirus and thus introduces the human immune system to the enemy even before their first meeting.
Conventional clinical trials for vaccines are extremely difficult to do: this would require intentionally exposing people to a dangerous virus. Therefore, the tests are carried out directly in the field: a compassionate use is established for the vaccine, that is, in order to receive it, it is necessary to provide evidence that the person is really at risk.
Because of this, Erwebho has so far been used only for so-called “ring vaccination” – a strategy that eradicated smallpox virus in the 1970s – only those who were in direct contact with the sick people. This method requires a lot of effort, and it is technically much more difficult to apply than mass vaccination. However, about 16,000 people have received the Erwebo vaccine so far, and the European Medical Agency has found evidence of its safety and effectiveness Convincing.
In October, the Agency recommended the vaccine for approval by the European Commission. Such applications usually take several months to process, but this time the Commission has expedited the procedure and made a decision in less than a month. However, in the Republic of the Congo itself, the vaccine has not yet been approved and will still be distributed through charity-testing. However, it will now be much easier for Merck to organize vaccine shipments to Africa.