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Canadian smallpox contingency plan calls for
containment, limited vaccination
By HELEN BRANSWELL
TORONTO (CP) - Hundreds of emergency and public health workers in Canada
will be given the opportunity to be vaccinated against smallpox this winter
as Health Canada takes steps to protect the country against a possible
resurgence of the deadly disease at the hands of terrorists, the department
announced Friday.
"The original number that's been discussed widely is 500, but actually
that was a notional number for planning purposes. We do not think it will be
that small," said Dr. Ron St. John, director general of Health Canada's
Centre for Emergency Preparedness and Response.
Federal officials are in discussions with provincial and territorial
governments to identify who and how many "first-line responders" - people
like emergency room doctors and nurses, ambulance drivers and public health
officials - should be inoculated with the risky smallpox vaccine in order to
be able to contain a outbreak should it occur.
"Our principle is to have the smallest number possible, because of the
side-effects, but still adequate to have an effective response," St. John
said in a media briefing on the country's smallpox contingency plan.
The briefing was arranged to answer the inevitable questions about
Canadian policy that would have arisen in the wake of President George W.
Bush's revelation Friday of a U.S. smallpox vaccination plan.
Bush ordered U.S. troops serving in high-risk areas to be inoculated,
adding that he, as commander in chief, would get vaccinated as well.
Prime Minister Jean Chretien's office said Friday he has no plans to get
vaccinated against smallpox.
The plan Bush announced will see about 450,000 U.S. civilian health care
workers also offered access to the vaccine, but discourages the public from
seeking vaccinations. Bush said his family and staff will not be getting
smallpox inoculations.
While Canada is in the process of buying 10 million doses of smallpox
vaccine to stockpile, there are no plans in this country to offer vaccine to
the general public. Nor is there a plan at this point to vaccinate members
of the Canadian Armed Forces.
"There are quite a few side-effects with this (vaccine), and the health
of our members is obviously a priority and we're not going to take any
unreasonable risks here," said navy Lieut. Diane Grover, a Defence
Department spokeswoman.
"If we were going to be deploying somewhere, we would have to look at the
risks that were presented both by the operation and by the geographic area."
The Canadian smallpox response policy calls for containing the disease by
rapidly inoculating people who have been in close contact with a person
suffering from smallpox.
The vaccine is risky because, unlike most vaccines, it is made with a
live virus - a close cousin of smallpox called vaccinia, also known as
cowpox. It cannot cause smallpox in people who take it, but can cause
serious side-effects.
St. John estimated that one to four people out of every million immunized
would die from the vaccine; and one in 300,000 would develop encephalitis or
swelling of the brain, which can lead to serious and lasting consequences.
As well, people can transfer the virus to other parts of their body by
touching the vaccination site; transferring the virus to the eye this way
leads to blindness.
Smallpox, which kills an estimated 30 per cent of the people who contract
it, was declared eradicated in 1980. The last known case occurred in Somalia
in 1977.
But both the United States and the former Soviet Union kept smallpox
stores. The Soviet Union is known to have weaponized smallpox, producing
tonnes of the virus in a covert biological weapons program. Not all of those
stores can be accounted for, and some experts are convinced some have fallen
into the hands of Iraq.
Both Canada and the United States discontinued mass smallpox vaccination
programs in 1972. Scientists aren't clear how much immunity people who were
vaccinated retain because it is known the vaccine's protection wanes over
time.
While smallpox is extremely contagious, elements of the disease make it
well suited to containment, St. John said.
People with smallpox are only infectious when they are in the full throes
of the disease, by which point the characteristic rash or pox and the degree
of sickness should make it clear to medical authorities what the person was
suffering from.
The disease also has a long incubation period - on average 10 to 12 days.
If a person is vaccinated within four days of exposure, the immune response
stops the disease from developing.
If a suspected case of smallpox is identified, a specimen will be rushed
to the National Microbiology Laboratory in Winnipeg for testing, with an
answer expected in 10 to 12 hours, St. John said. If a case were confirmed,
public health officials would identify any people who had come in contact
with the smallpox victim when he or she was infectious and inoculate them
within the four-day window.
"This means that the disease does not spread like wildfire through a
community," he said, noting the nightmare scenarios of terrorists infecting
themselves and then spreading the disease through an airport or a shopping
mall probably could not occur. "You cannot get out of bed when you have this
disease and you are infectious."
"It is not like influenza, it is not like measles," he added, referring
to two highly infectious diseases. "It spreads in predictable, expanding
circles of close contacts. And waves and waves of cases come every 12 to 14
days, which is the same as the incubation period."
St. John said other countries are also preparing to inoculate small
numbers of emergency workers. France is vaccinating a squad of 150
employees, Britain about 300 and Germany around 1,000.
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On the Net: the U.S. Centers for Disease Control, www.bt.cdc.gov/agent/smallpox
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