An Ebola vaccine developed by the Public Health Agency of Canada and tested in Guinea has turned out to be almost 100 percent effective, the World Health Organization said Friday, citing the British medical journal The Lancet.
The researchers used the newly-developed Ebola shot in so-called ring vaccination, the method that helped eradicate smallpox in the past. It is based on vaccination of all people who came into contact with an infected person, creating a so-called “protective ring” that prevents the disease from spreading.
More than 7,000 adults were included in 90 clusters to take part in the study. About 4,000 of those involved were assigned to immediate vaccination after confirmation of the contact with an infected person and about 3,000 others to delayed vaccination 21 days after the contact. Pregnant and breastfeeding women were excluded from the test.
In the period between April 1 and July 20, more than 3,500 people were vaccinated. As a result, no patient got sick with Ebola after immediate vaccination whereas 16 people got sick among those who got delayed vaccination. In other words, current findings show near-100 percent efficiency of the vaccine.