A dose of the Pfizer-BioNTech COVID-19 vaccine is pictured at a vaccination site in Vancouver Thursday, March 11, 2021. Grocery workers 18 and up in one B.C. region can register for vaccine. Grocery workers aged 18 and up are now eligible to register for a Pfizer-BioNTech or Moderna vaccine in British Columbia's largest health region. THE CANADIAN PRESS/Jonathan Hayward

SURREY, B.C. - The first person in British Columbia to have a rare blood clot associated with the Oxford-AstraZeneca vaccine has been hospitalized after a family doctor quickly recognized her symptoms, the provincial health officer says.

Dr. Bonnie Henry said Thursday the woman in her 40s contacted her physician about symptoms five or six days after being vaccinated and a blood test confirmed the clot linked to the rare condition.

A monitoring program in B.C. provides all doctors with information reminding them of symptoms to look for in case of a clot in the veins or arteries of the legs or arms and in very unusual cases, veins in the brain, Henry said.

She said the likelihood of such clots is about one in 100,000 doses and anyone with symptoms such as a persistent severe headache, chest pain and swelling or redness in a limb should seek medical help right away.

"I want to make sure that people are monitoring for these unusual symptoms and I know that many people have lots of anxiety about that. So take a deep breath and be assured that this is rare, that physicians know what to do and that if you have concerns that you contact your health-care provider," she said.

"We only have to look at places like the U.K. to see how beneficial it has been to stop the outbreaks that we've been seeing," she said of AstraZeneca, which has been linked to three deaths in Canada since last month.

Henry said anyone who has had the vaccine can choose to get a different one for their second dose and switching between any two vaccines may provide better protection against COVID-19, but more details on that will be available in the coming weeks after the results of a study in the United Kingdom.

British Columbia was expected to reach a vaccination milestone on Thursday, with over two million vaccines administered, representing nearly half of over 4.3 million eligible residents.

The province is mostly getting the Pfizer vaccine now, after a slowdown in deliveries of AstraZeneca, Henry said.

Health Canada anticipates a total of 36.5 million doses from Pfizer-BioNTech, Moderna as well as AstraZeneca from the Serum Institute of India by June 30, though supplies from that country are expected to be disrupted because of a worsening COVID-19 crisis.

Grocery workers aged 18 and up were asked Thursday to register for the Pfizer or Moderna vaccine in Fraser Health, the province's largest region and home to a high number of essential workplaces.

Dr. Victoria Lee, CEO of Fraser Health, said COVID-19 has spread quickly in the area's multi-generational homes where disadvantaged people don't always find it easy to get away to get vaccinated.

"There can be difficulties in terms of having protection at workplaces to prevent transmission as well, so all of that together has led to a greater number of cases and transmission."

She said more options will soon be available in Surrey, for example, like vaccination at places of worship, including temples and mosques.

Henry said she, Premier John Horgan and Health Minister Adrian Dix met this week with leaders of the South Asian and Chinese communities to better understand their needs related to registration and appointments for vaccines.

The single-shot Johnson & Johnson vaccine, which has been approved in Canada, may be preferred for some populations so they are not required to return for a second shot, Henry said.

She said other provisions, such as sick leave, will also make a difference after it is legislated in the province in the coming weeks.

British Columbia recorded 694 cases of COVID-19 on Thursday, and one more death for a total of 1,592 fatalities from the virus.

— By Camille Bains in Vancouver

This report by The Canadian Press was first published May 6, 2021.

News from © The Canadian Press, 2021