A Winnipeg lab claims it has created an effective Ebola vaccine
It appears the world finally has an effective Ebola vaccine. A new study reported Friday that a vaccine designed by scientists working at Canada’s National Microbiology Laboratory in Winnipeg induces a quick and highly protective response against the viru
This is the first time an experimental Ebola vaccine has been shown to protect people against the deadly disease. The former director of the Winnipeg lab, Dr. Frank Plummer, was ecstatic about the news.
“I think it’s fantastic. For the NML and the whole team that was involved in this, it’s the culmination of 15 years of work. It’s very, very exciting. Very, very gratifying,” said Plummer, who led the lab when the work was being done, but retired from that job last year.
“If proven effective, this is going to be a game-changer,” said Dr. Margaret Chan, Director- General of the World Health Organization. “It will change the management of the current outbreak and future outbreaks.”
“It looks to be about as safe as a flu vaccine,” said Ben Neuman, a virologist at the University of Reading who wasn’t part of the trial.
Researchers are still assessing possible side effects; the most serious seemed to be fever and the stress experienced by patients who believe such symptoms were due to Ebola.
“This (vaccine) could be the key that we’ve been missing to end the outbreak,” Neuman said. “I don’t see any reason on humanitarian grounds why it shouldn’t be used immediately.”
He said further tests would be necessary to see if the vaccine might also protect pregnant women, children and adolescents. Those trials are already under way.
There were high hopes that this vaccine, called rVSV-ZEBOV, would be effective. But in science, assumptions don’t count — data does.
And the data from this trial, conducted in Guinea, is persuasive, suggested Dr. Marie-Paule Kieny, a senior author of the trial and the World Health Organization’s point person for development of Ebola vaccines and drugs.
“It works, it works pretty quickly, and it works well,” Kieny said.
In fact, the vaccine protected 100 per cent of the people who received it. While experts caution that number will probably come down when the vaccine is used in more people, it’s a very good result.
The study was actually meant to continue for a longer time, but an interim analysis conducted by the trial’s data and safety monitoring board concluded the vaccine was working. The board of outside experts advised the researchers to stop using a control group and offer the vaccine going forward to all the people who met the criteria for the study.
The study was led by the WHO and involved a variety of partners including the Public Health Agency of Canada.
The trial was conducted using a ring vaccination design.
The idea behind ring vaccination is to create a buffer of protection around each case, so that the virus can’t continue to spread. This is actually the way the scientists who designed the vaccine intended for it to be used.
When new cases of Ebola were diagnosed, the researchers offered to vaccinate people who had been in contact with the infected person, and the contacts of those contacts.
Some of the rings of people were vaccinated immediately. Others were told they would be vaccinated after a delay of three weeks. And then researchers watched to see how many people in the two types of rings became infected.
In the first few days, there were infections in both rings. That’s not surprising; a vaccine takes time to kick start the immune system to protect against a new pathogen. But after 10 days, they saw no additional cases in the rings of vaccinated people. However, new cases continued to crop up in the rings of people who were randomly assigned to get vaccinated after the three-week delay.
“We have nobody in the 2,000 or so people who have been vaccinated (early) who have had an Ebola (diagnosis) 10 days after the vaccination. Nobody, zero,” said Kieny.