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COVID-19 VACCINE

IH doctors explain how COVID-19 vaccine protects against the virus

Dec 23, 2020 | 4:41 PM

KAMLOOPS — On Tuesday (Dec. 22), COVID-19 vaccinations began in Kamloops. 975 doses of the Pfizer-BioNTech vaccine arrived in the city this week, a shipment that is expected to arrive on a weekly basis. First to receive the vaccine are long term care workers.

“So the first priority group for vaccination is the long term care workers, followed by the long term care residents,” said Medical Health Officer Dr. Carol Fenton. “After that we will do our COVID frontline workers, so emergency medicine physicians, ICU physicians and nurses and workers in the testing centres for example.”

Fenton says because of the need to store it at an extremely cold temperature, the Pfizer vaccine has so far been administered where it’s been delivered.

“The Moderna product has more stability data,” she said. “We’ve been told that we’re allowed to transport it. So once we have the Moderna (vaccine) we’ll be able to go to clinics, we’ll be able to long term care and get those populations that cannot travel to the bigger centres to get their vaccine.”

According to Dr. Bonnie Henry, the province has now been given permission to transport the Pfizer vaccine as well.

Both products are messenger RNA (mRNA) vaccines.

“I always say that you’re circulating a mug shot to the police departments,” explained Dr. Annemie Raath, a hospitalist at Royal Inland Hospital who has been working in the COVID unit on and off throughout the pandemic. “So, it doesn’t contain any part of the virus itself, but it’s a little part of RNA on the virus that they mimic called the spike protein, which is a big part of how the virus makes you sick. What it then does is it circulates this photo to your body which then replicates that and then reacts to it and forms antibodies to it.”

Infectious Disease Specialist Dr. Elizabeth Parfitt says those antibodies begin to develop within seven to 14 days after the first dose of the vaccine.

“Although there was some protection demonstrated even after the first dose, we’re really not going to be considering people likely immune until a week or two after the second dose,” Parfitt said.

Today (Dec. 23), Dr. Henry announced the second dose of the vaccine will be administered approximately 35 days after the first dose.

Even after a person is fully vaccinated, it’s recommended they continue to wear their masks, wash their hands and physically distance from others. This is because there is not enough data on whether a vaccinated individual can still transmit the virus.

“We don’t want the conclusion to be that it won’t protect from onward transmission,” Parfitt said, “but we just need to know. Now we’re in that post-marketing phase where we’re going to be collecting information from all of the people who have been immunized over the next weeks and months. We’re going to have more data as every day goes by.”

Vaccine recipients may notice some side effects, but doctors say in most cases these are not a serious concern.

“People shouldn’t panic,” Raath said. “This is not an infection, it’s just simply your body’s response. Fever and muscle aches are a large part of how your body responds to infection and helps it fight off infection. So it’s really just your body mimicking that and building up immunity.”

As the vaccine is distributed across Canada, a new variant of COVID-19 in the United Kingdom is being watched carefully.

Dr. Parfitt says that while mutations of viruses are common, the variant discovered in the UK has accumulated a larger number of mutations than previously seen with COVID-19. There is concern that the virus could be more transmissible.

“What I’ve been trying to impress upon my colleagues and friends and family and whoever will listen to me is that there’s a lot of things through this pandemic where there’s a red flag, we need to give it some time to learn more about it,” Parfitt said. “Right now I’m hearing from experts in vaccinology and virology that this probably will not affect the current vaccine in terms of its efficacy and effectiveness in the real world.”

Canada has banned flights from the UK until Jan. 6.

The benefit of the mRNA vaccine technology is that it can be tweaked.

“If we do need to update this vaccine from time to time because of mutations or just because our antibody levels or immunity wanes over several years we can do this again and adjust the technology so that the new variant will be covered in future vaccine rollouts.”

All Canadians are expected to have an opportunity for vaccination by the end of 2021.