Canada recommends mixing, matching of Covid-19 vaccines

Canada on Tuesday recommended mixing and matching of AstraZeneca Pfizer and Moderna Covid19 vaccinesThe National Advisory Committee on Immunization NACI updated its guidance to provinces and territories on mixing and matching second doses of Covid19 vaccines and advised Canadians to combine either the AstraZenecaOxford PfizerBioNTech or Moderna shots interchangeably in certain situations reported CBC NewsNACI guidance is based on early research from UK Spain that shows mixing shots of AstraZeneca and Pfizer vaccines was both safe and effective at preventing Covid19 It recommended that a first shot of the AstraZeneca vaccine can be followed by either Moderna or PfizerFor Canadians who have had a first dose of Moderna or Pfizer NACI recommended they can now take either of the two shots as a second dose because they both use a similar mRNA technology if the same first dose is unavailable or unknownCBC News first reported the details of the recommendation changes Tuesday morning based on information from sources with direct knowledge of the decision who spoke on condition of anonymityThe details of the shift in guidance were confirmed publicly by officials from the Public Health Agency of Canada during a news conference Tuesday afternoon reported CBC NewsAlso read Consignment of 3 million doses of Sputnik V vaccine from Russia land in HyderabadCanadas Chief Public Health Officer Dr Theresa Tam said the decision to combine mRNA vaccines interchangeably was nothing new and that the same principle had been applied to different types of vaccines in the past including shots for influenza and Hepatitis AThis is not a new concept so having a multidose series in terms of vaccines given by manufacturers is something that public health have used over time for many other vaccines Tam said When vaccines programs and supplies change this is not an unusual thing to doThe updated NACI recommendations stated No data currently exist on the interchangeability of Covid19 mRNA vaccines but Tam said there are ongoing studies on the effectiveness of the approach that have yet to be published The decision was made based on the similar makeup of the vaccines which both target the spike protein of the coronavirus she saidThe recommendations will have a major impact on Canadas vaccine rollout with previous NACI guidelines stating that a vaccination series that begins with AstraZeneca should follow up with the same type of shot and that mRNA vaccines should only be used interchangeably if the same first dose is unavailable or unknown reported CBC NewsThe updated guidelines follow moves by some provinces to combine different shots due to issues with the supply of AstraZeneca and a rare but serious type of blood clot that can result after the shot called vaccineinduced immune thrombotic thrombocytopenia VITT which NACI also cited as a reason for its decision in its guidanceMore than 13 million people have received at least one dose of the Pfizer vaccine in Canada in contrast to over 35 million of the Moderna vaccine and more than 21 million of the AstraZeneca vaccine as of May 22 according to the latest available federal government dataDr Zain Chagla an infectious diseases physician at St Josephs Healthcare Hamilton and an associate professor at McMaster University says the proposed approach to mixing and matching Covid19 vaccines by NACI is reasonable based on available international dataPfizer and Moderna are so interchangeable I doubt theres going to be any difference between the two he said Their immune responses should be pretty similarThe Public Health Agency of Canada PHAC now estimates the rate of VITT in Canadians who have received the AstraZeneca vaccine is between 1 in 83000 and 1 in 55000 with a fatality rate of between 20 and 50 per cent but that is subject to change as more data emerges reported CBC NewsPHAC said in a statement to CBC News Thursday there have been 27 confirmed cases of VITT to date in Canada out of two million doses administered with five deaths among those casesThis story has been sourced from a third party syndicated feed agencies Midday accepts no responsibility or liability for its dependability trustworthiness reliability and data of the text Midday managementmiddaycom reserves the sole right to alter delete or remove without notice the content in its absolute discretion for any reason whatsoever