Military stockpiling unapproved vaccine - Canada
http://www.canada.com/nationalpost/news/canada/story.html?id=ba7d1738-e342-4934-899d-42c4f62f647b
Smallpox Threat, Tom Blackwell, National Post
The Canadian Forces are stockpiling thousands of doses of a smallpox vaccine that has yet to be approved by North American regulators but is supposed to virtually eliminate the sometimes lethal side effects of immunizing against the virus.
It is the latest example in recent years of the Forces buying anti-terrorism medical products that have not been licensed by Health Canada and have to be acquired under the regulator's "special access" program.
Conducting the pricey trials needed for government approval is often financially unfeasible for products geared solely toward the military, National Defence Department officials say. In some instances, it would also be unethical to test countermeasures against nerve gases or other biological and chemical weapons on humans, since the subjects would have to be exposed to the deadly toxin.
In the case of the "modified vaccinia ankara" (MVA) vaccine being ordered by the military, trials are underway and it could be licensed within two years, but the department wants to buy at least 10,000 doses now in case it is needed by troops urgently, said Dr. Francis Souter, in charge of biological warfare countermeasures at the department. Negotiations with the manufacturer are still underway so no cost is available yet.
If a smallpox attack became a real danger, the new product would be administered to the 10% of military personnel thought to be most at risk from vaccine side effects, Dr. Souter said.
"Our hope is that we would never have to use it. It's there only for use after a very careful benefit-risk analysis, threat-risk analysis," he said. "[But] the vaccine does not replicate in the body like the normal one. The side effects associated with it, the safety profile, is much better as a result."
Acquiring the vaccine now despite its lack of licence would seem like a reasonable move, especially since a similar product was actually used experimentally on about 100,000 people in the early 1970s, said Andrew Potter, head of the Vaccine and Infectious Disease Organization at the University of Saskatchewan. "The fact a [version] of it has been in a fairly large number of people ... would probably give a fair level of comfort," he said.
Naturally occurring smallpox, with its 30% death rate, became the first, and to date only, infectious disease to be eradicated worldwide in the early 1970s, thanks to immunization. Samples of the virus still exist, however, at labs in the United States and Russia, raising fears it could get into the hands of terrorists or be used by conventional armies.
Canada and other countries began stockpiling vaccine in the wake of the 9/11 attacks, and the United States has vaccinated thousands of health workers and military personnel since then.
Canadian troops, including those serving in Afghanistan, have not been given smallpox vaccine yet, Dr. Soutter said.
Traditional vaccines introduce a live, replicating virus that builds up an immune response within days, and so can cause problems for people with compromised immune systems or certain other conditions. Because it is pricked into the skin, rather than injected, the vaccination site can also transmit virus to others.
The MVA vaccine is non-replicating, so it seems to pose less threat to the immune compromised, and is injected, meaning there is a smaller chance of transmission.
Smallpox Threat, Tom Blackwell, National Post
The Canadian Forces are stockpiling thousands of doses of a smallpox vaccine that has yet to be approved by North American regulators but is supposed to virtually eliminate the sometimes lethal side effects of immunizing against the virus.
It is the latest example in recent years of the Forces buying anti-terrorism medical products that have not been licensed by Health Canada and have to be acquired under the regulator's "special access" program.
Conducting the pricey trials needed for government approval is often financially unfeasible for products geared solely toward the military, National Defence Department officials say. In some instances, it would also be unethical to test countermeasures against nerve gases or other biological and chemical weapons on humans, since the subjects would have to be exposed to the deadly toxin.
In the case of the "modified vaccinia ankara" (MVA) vaccine being ordered by the military, trials are underway and it could be licensed within two years, but the department wants to buy at least 10,000 doses now in case it is needed by troops urgently, said Dr. Francis Souter, in charge of biological warfare countermeasures at the department. Negotiations with the manufacturer are still underway so no cost is available yet.
If a smallpox attack became a real danger, the new product would be administered to the 10% of military personnel thought to be most at risk from vaccine side effects, Dr. Souter said.
"Our hope is that we would never have to use it. It's there only for use after a very careful benefit-risk analysis, threat-risk analysis," he said. "[But] the vaccine does not replicate in the body like the normal one. The side effects associated with it, the safety profile, is much better as a result."
Acquiring the vaccine now despite its lack of licence would seem like a reasonable move, especially since a similar product was actually used experimentally on about 100,000 people in the early 1970s, said Andrew Potter, head of the Vaccine and Infectious Disease Organization at the University of Saskatchewan. "The fact a [version] of it has been in a fairly large number of people ... would probably give a fair level of comfort," he said.
Naturally occurring smallpox, with its 30% death rate, became the first, and to date only, infectious disease to be eradicated worldwide in the early 1970s, thanks to immunization. Samples of the virus still exist, however, at labs in the United States and Russia, raising fears it could get into the hands of terrorists or be used by conventional armies.
Canada and other countries began stockpiling vaccine in the wake of the 9/11 attacks, and the United States has vaccinated thousands of health workers and military personnel since then.
Canadian troops, including those serving in Afghanistan, have not been given smallpox vaccine yet, Dr. Soutter said.
Traditional vaccines introduce a live, replicating virus that builds up an immune response within days, and so can cause problems for people with compromised immune systems or certain other conditions. Because it is pricked into the skin, rather than injected, the vaccination site can also transmit virus to others.
The MVA vaccine is non-replicating, so it seems to pose less threat to the immune compromised, and is injected, meaning there is a smaller chance of transmission.