New Ebola vaccine provides 100% protection
Ebola was first discovered in 1976, and before the 2014 outbreak, it typically hit isolated African communities, those outbreaks were much more manageable for medical teams to parachute in and treat patients. But the virus reached cities in 2014, spreading like wildfire and catching the global health community off guard.
In a scientific triumph that will change the way the world fights a terrifying killer, an experimental Ebola vaccine tested on humans in the waning days of the West African epidemic has been shown to provide 100 percent protection against the lethal disease.
Nearly 6,000 people in Guinea were given the test vaccine last year, at the tail end of a lethal epidemic of Ebola. Not one of the 6,000 contracted the disease.
When analyzing the results, the teams didn't count people who got sick within the 10 days, as they were believed to have been infected before they received the vaccine. Waiting 10 days also gave volunteers time to build up immunity after receiving the vaccine, according to Dr. Marie-Paule Kieny, the WHO assistant director-general and the study's lead author.
Researchers followed up with immunized volunteers at their homes on days three, 14, 21, 42, 63 and 84 after receiving the vaccine.
A total of 5,837 people were given the vaccine, and none had a recorded case of Ebola after 10 days or longer, the study says.
But in a control group of volunteers that did not receive the vaccine, 23 Ebola cases occurred, researchers reported in The Lancet medical journal.
"If we compare zero to 23, this strongly suggests that the vaccine is very effective, that it could be up to 100 percent effective," Marie-Paule Kieny, WHO's assistant director-general and lead author of the study, told AFP.
Her team of three dozen researchers calculated a 90-percent likelihood during a full-fledged epidemic that the vaccine, dubbed rVSV-ZEBOV, would work in more than 80 percent of cases.
The new vaccine was initially developed in Canada by public health authorities before being taken over by pharmaceutical giant Merck.
It is slated to be submitted by Merck to health authorities in the United States and Europe sometime next year under a fast-track approval process.
In the meantime, Merck has committed to ensuring that 300,000 doses of the vaccine are available for emergencies under a protocol called "compassionate use".