Ebola vaccine breakthrough


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Jun. 6, 2005. 06:27 AM

Ebola vaccine breakthrough

Winnipeg facility hailed for strides on two killer viruses

Possibility of bio-terrorism attack was strong factor, MD says

ELAINE CAREY

MEDICAL REPORTER

Jubilant Canadian researchers have announced a world breakthrough in developing vaccines against the lethal Ebola and Marburg viruses.

Working with the U.S. Army, researchers at Health Canada's National Microbiology Laboratory in Winnipeg have produced a single-dose vaccine that successfully protects monkeys against the two closely related viruses.

The viruses, which have killed hundreds of people in central Africa this year alone, are considered a potential bio-terrorism threat and have no known treatment or cure. It is the first time a Marburg vaccine has been shown to work in monkeys.

A human vaccine could be ready for production in five to six years, but it could be fast-tracked for use sooner in response to an emergency, Dr. Steve Jones of the laboratory told a news conference in Winnipeg on Friday. It was held in advance of the announcement which was embargoed until yesterday when it was published in the journal Nature Medicine.

The vaccine for "two of the most lethal organisms we know of" highlights the scientific capacity Canada has built up at the Winnipeg facility, one of only three highly secure Level 4 labs in the world, and also the importance of international co-operation, said Dr. Frank Plummer, its scientific director-general.

"This group established in Winnipeg has gone through leaps and bounds on the world stage," he said. "It is truly a world-class facility."

The vaccine breakthrough is "all the more remarkable" because the team has been busy in the last several years working on other infectious disease outbreaks, including SARS and a vaccine against a potential pandemic influenza outbreak, Plummer said.

Before the break-up of the Soviet Union, it was known to be working on Ebola and Marburg as bioterrorism weapons, said Dr. Tom Geisbert of the U.S. Army Medical Research Institute of Infectious Diseases in Fort Detrick, Maryland.

Victims of the viruses suffer a high fever, diarrhea, vomiting and severe gastrointestinal bleeding and usually die within a week.

Jones, who just returned from Angola where he was working with the World Health Organization on a Marburg outbreak that has claimed 335 lives, said he has "a good deal of confidence" the vaccine will work in humans because monkeys get the same type of severe disease as humans do.

Victims of the viruses suffer high fever, diarrhea, vomiting, gastrointestinal bleeding and usually die within a week

"One of most nasty, foul things about this disease is that it is spread in close contact and therefore those people who are brave enough to treat the patients and take care of them in their final days are the people most likely to succumb to an infection themselves," he said.

"This is why you see these diseases spread through families ... If you could use this vaccine in the field you could protect those people who are putting their lives at risk and their loved ones. I think that's a significant and important use of this vaccine in the real world.

But the agency's main concern is "to prepare for what we hope is the unthinkable ? an outbreak of the virus on Canadian soil or the use of agents as potential biological terror weapon agents," he said.

"We all assume a bio-terrorism attack in Canada is extremely unlikely. ... But we would be remiss if we didn't make preparations for the unthinkable."

The aim is eventually to produce enough human vaccine to stockpile it against such a threat, Jones said. It now takes 28 days for the monkeys to fully develop immunity to the viruses, but they hope to cut that time in half, he said.

The live vaccine is attenuated, meaning it looks like the virus but causes none of the symptoms and produced a completely effective immune response in 12 macaques (a type of monkey), half of whom were given the Ebola vaccine and half the Marburg. Twenty-eight days later, they were injected with one of the viruses and none of them developed any symptoms.

The initial development and testing of the vaccines was done at the Winnipeg lab over the past three years and the primates were tested at the U.S. army's research institute in Maryland.

If the vaccine does prove to work successfully in humans, 80 per cent of the people who get the viruses will survive, compared to the current death rate of 100 per cent, Jones said.

While there was no "Eureka moment" when the team of researchers realized they had a breakthrough, there was "a great, great moment" when they realized that the 12 monkeys had survived being injected with the virus, he said.

Geisbert, who has worked on the Ebola and Marburg for 17 years, said there was "no greater feeling than to walk into the lab seven to 10 days later see that the monkeys were still healthy. It's a fantastic feeling."

The U.S.-Canada collaboration began as a friendship between Geisbert and Dr. Heinz Feldman in Winnipeg who were working on the viruses "back when nobody cared about Ebola or Marburg," Geisbert said.

http://www.thestar.com/NASApp/cs/ContentSe...id=968332188492

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And my friend moved to San Francisco because she said there was no research being done in Canada.

Mind you, if I had the choice of San Francisco of Winnipeg... Well, no offence Boffa.

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The live vaccine is attenuated, meaning it looks like the virus but causes none of the symptoms and produced a completely effective immune response in 12 macaques (a type of monkey), half of whom were given the Ebola vaccine and half the Marburg. Twenty-eight days later, they were injected with one of the viruses and none of them developed any symptoms.

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WHOOOO, SPOOKY

Correct me if i'm wrong, but doesn't 'vaccine' mean that it's only useful if they give it to people before they get the virus? So... i mean, although i'm sure it'll be very helpful for the people in Africa who fall victim to (natural) out-breaks all the time, i don't see it being that great as far as bioterrorism unless they start actually vaccinating people for it soon.

And even then, you've only solved part of the problem. Nobody born after like 1979 has an immunity to smallpox, so there's that. And then there's botulism and the weaponised plague.

I don't know, that's cool for Africa, but it doesn't make me feel any better about bioterrorism. (Not that i'm necessarily worried about it right now.)

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WHOOOO, SPOOKY

Correct me if i'm wrong, but doesn't 'vaccine' mean that it's only useful if they give it to people before they get the virus? So... i mean, although i'm sure it'll be very helpful for the people in Africa who fall victim to (natural) out-breaks all the time, i don't see it being that great as far as bioterrorism unless they start actually vaccinating people for it soon.

And even then, you've only solved part of the problem. Nobody born after like 1979 has an immunity to smallpox, so there's that. And then there's botulism and the weaponised plague.

I don't know, that's cool for Africa, but it doesn't make me feel any better about bioterrorism. (Not that i'm necessarily worried about it right now.)

586024225[/snapback]

If the government stocks up enough of these vaccines (ebola, smallpox) then they could start to vaccinate citizens at the first sign of an outbreak. It would still kind of suck to be patient zero (or anyone who came in contact with him/her) but at least they can have a plan.

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It'd be better than nothing, i guess, but a vaccine really doesn't make me feel THAT much better about it. It wouldn't spread to the rest of the country or anything if it was released in, say, Toronto, but it could very well infect tons and tons of people before they even realise it. Ebola can incubate for up to a month before people start to show symptoms, and after that it takes ANOTHER month for the vaccine to be effective. :/

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