Frozen lot of unrevealed Ebola vaccine traced by Merck will be donated to Uganda for testing

The American multinational pharma company Merck has revealed that it has about a hundred thousand doses of an untried vaccine for Ebola in storage in Pennsylvania, which will be donated to Uganda to counter the outbreak.

This vaccine was aimed at Sudan ebolavirus, which has found its way to Uganda. The vaccine was produced by Merck discreetly in 2015-16 following its success with a similar ebola vaccine for the Zaire Ebola virus that was an epidemic from 2014 to 2016 in Western Africa. Merck had frozen the vaccine and did not test it on anyone. The vaccine had very good results when tested on monkeys as it protected them from the Sudan ebolavirus and this is why the hopes are high in terms of its safety and effectiveness.

Mark Feinberg had led Merck’s Zaire Ebola program and said that this revelation is great news as it enables the vaccine to be tested at a faster pace than otherwise possible. Merck had acknowledged the existence of the vaccines in mid-October and said that the vials were demolished due to expiration. However, after some probing Merck said that the vaccine exists in bulk, was deemed viable after testing, and will be donated. According to the company, the vaccine is being filled in vials and will take about a month.

As of October 22^nd, Sudan ebolavirus has killed (28) over a third of the people it has affected (75). This is the first outbreak in a decade for Uganda and is particularly dangerous because some cases have been reported in Kampala as well, which has a population of 1.5M. This announcement by Merck has elevated hopes that Uganda can be quick in dealing with the virus.

The vaccine by Merck is VSV (vesicular stomatitis virus) joined with the surface protein gene of the Sudan ebolavirus. A vaccine with the same build was used against the Zaire ebolavirus and proved to be effective. The vaccine was approved by European Union and U.S. regulators after its triumph in 2015 Guinea trials.

University of Oxford and Sabin Vaccine Institute are two other entities working on a vaccine for Sudan Ebola. Both of these entities use chimpanzee adenoviruses to transfer the gene of the surface protein into the body and are working to produce sufficient doses for Uganda trials.

Many scientists have shown confidence in all three vaccines’ ability to protect against the virus. The clear most promising candidate for them is Merck’s, due to the copying ability of VSV against the chimpanzee adenovirus.

WHO was partnering with health reps in the country to come up with a protocol for the testing of Sabin and Oxford vaccines with a strategy that is called ‘ring vaccination’. In this strategy, the vaccine is used on infected peoples’ direct contacts and perhaps contacts of contacts. This method was also used at the time of Zaire Ebola in Guinea.

A WHO spokesperson said that an independent group of experts is presently studying the evidence and will recommend which vaccine should be the first to be tested.