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AP Photo/ Youssouf Bah, File
No vaccine has proven this effective.

A new “game-changing” Ebola vaccine is confirmed as 100% effective if taken early

Hanna Kozlowska
By Hanna Kozlowska

Investigative reporter

Researchers say they have finally found a vaccine that could provide complete protection against Ebola, a deadly virus that has been raging in several countries in Western Africa for two years, killing more than 11,000 people.

World Health Organization (WHO) chief Margaret Chan called the results of a trial in Guinea “game-changing.” It involved more than 3,500 people; 2,000 received the vaccine soon after coming in close contact with someone with Ebola, and the rest received the vaccine 21 days after contact.

Initial results, published in the medical journal Lancet, show that when the vaccine was administered immediately, it was 100% effective after 10 days. If the subjects were vaccinated later, however, they were still at risk of getting infected. Nevertheless, the vaccine, made by pharmaceutical company Merck, is the first to have such promising results.

The accelerated trial started in March. The charity Doctors Without Borders says the results are “promising” and is pushing to vaccinate at-risk people in Ebola hot-spots as soon as possible.

“Too many people have been dying from this extremely deadly disease, and it has been very frustrating for healthcare workers to feel so powerless against it,” said the group’s medical director, Bertrand Draguez. “More data is needed to tell us how efficacious this preventive tool actually is, but this is a unique breakthrough.”

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