echemi logo
Product
  • Product
  • Supplier
  • Inquiry
    Home > Medical News > Latest Medical News > AstraZeneca's new crown vaccine is linked to slightly increased risk of bleeding disorders

    AstraZeneca's new crown vaccine is linked to slightly increased risk of bleeding disorders

    • Last Update: 2021-06-16
    • Source: Internet
    • Author: User
    Search more information of high quality chemicals, good prices and reliable suppliers, visit www.echemi.com
    Nature News: AstraZeneca's new crown vaccine is linked to a slight increase in the risk of bleeding diseases
    Nature sub-journal: AstraZeneca's new crown vaccine is associated with a slight increase in the risk of bleeding diseases.


    At the time of the global pandemic of the new crown, vaccines are being placed with high hopes of restarting the world
    .


    However, reports on the Oxford-AstraZeneca new crown vaccine ChAdOx1 related thrombocytopenia and vascular adverse events have caused some countries to restrict its use, and at the same time, to a certain extent, reduce the enthusiasm of some members of the public to vaccinate


    At 23:00 on June 9th, Beijing time, the top international academic journal "Nature Medicine" (Nature Medicine) published online a study completed by the British team, entitled "First-dose ChAdOx1 and BNT162b2 COVID-19 vaccines and thrombocytopenic" , thromboembolic and hemorrhagic events in Scotland"
    .


    The study conducted a nationwide survey of more than 2.


    Investigations have shown that the Oxford-AstraZeneca vaccine is associated with a slightly increased risk of an autoimmune hemorrhagic disease, immune thrombocytopenic purpura (ITP)
    .


    The study also found that there may be evidence that the Oxford-AstraZeneca vaccine is associated with an increased risk of other bleeding and vascular problems


    The British team emphasized that public health authorities should inform their jurisdictions of these relatively small increases in risks associated with ChAdOx1
    .


    "If the supply of the new crown vaccine is sufficient, it may be necessary to provide the public with other alternative vaccines


    "Nature-Medical" also published opinion articles written by Douglas B.
    Cines of the University of Pennsylvania in the same journal
    .


    Cines et al.


    1.
    13 out of every 100,000 injections of the first dose

    1.
    13 out of every 100,000 injections of the first dose

    The paper writes that the three vaccines currently used in the UK are the Oxford-AstraZeneca new crown vaccine ChAdOx1, Pfizer-BioNTech's new crown vaccine BNT162b2 and Moderna's mRNA-1273, all of which have been proven to reduce COVID-19 infection
    .


    Given that the first dose of mRNA-1273 was only carried out in Scotland on April 7, 2021, this study focused on ChAdOx1 and BNT162b2


    Previous clinical trials have shown that the two vaccines ChAdOx1 and BNT162b2 for the new coronavirus are generally well tolerated, but there are a few reports of serious side effects
    .


    After 22 million first injections and 6.


    The European Medicines Agency also listed thrombosis with thrombocytopenia as a rare side effect of the AstraZeneca vaccine in April, but still believes that the benefits of vaccination outweigh the risks, and EU member states decide whether to continue using it
    .

    In order to investigate the possibility that the new crown vaccine is related to the progression of blood diseases, Aziz Sheikh and colleagues at the University of Edinburgh in the United Kingdom investigated the first dose of the new crown vaccine between December 2020 and April 2021 (the most common ones are ChAdOx1 or BNT162b2).
    ) 2.
    53 million Scottish adults (57% of the adult population over the age of 18) were associated with vaccine-related bleeding and vascular events
    .

    The research team found that in the survey population, ChAdOx1 vaccine was associated with a slight increase in ITP risk for up to 27 days after injection.
    The disease caused slight bruising and excessive bleeding in some patients, and some patients developed chronic diseases
    .


    It is estimated that 1.
    13 cases occur out of every 100,000 injections of the first dose
    .

    The analysis also showed that within 27 days of ChAdOx1 injection, there was a slight increase in the risk of other arterial thrombosis and bleeding events
    .
    However, there is insufficient evidence that ChAdOx1 is related to cerebral venous sinus thrombosis (a rare disease that forms a blood clot in the brain)
    .

    At the same time, the research team found no evidence that the BNT162b2 vaccine is associated with an increased risk of these adverse events
    .

    In the paper, the research team pointed out several limitations that should be paid attention to
    .
    Since few people received two doses of vaccine at the time of analysis, this subgroup (second dose) was not investigated separately, and the second dose will be further analyzed in due course
    .

    In addition, there are fewer young vaccinators (<40 years old) in this study, especially the ChAdOx1 vaccine, because the vaccination program has so far mainly prioritized older groups and groups with underlying underlying diseases
    .
    They pointed out that further research needs to include younger people and assess the response to the second dose of the vaccine
    .

    Limitations also include the need for the study to assume that clinicians have properly investigated the patient's thrombocytopenia before recording the diagnosis of ITP
    .

    The research team concluded that in patients who received the BNT162b2 vaccination, they did not find any increase in the overall risk of adverse events
    .
    The first dose of ChAdOx1 was associated with a slight increase in the risk of ITP, suggesting an increased risk of arterial thromboembolism and hemorrhagic events
    .

    In view of the slight increase in these risks of ChAdOx1, the study believes that if the supply of the new crown vaccine is sufficient, it may be necessary to provide the public with other alternative vaccines
    .

    "The balance between risk and benefit"

    "The balance between risk and benefit"

    The research team also emphasized that the benefits of ChAdOx1 are very clear, and these findings should be understood in this context
    .
    The risk of serious adverse events caused by the vaccine is much lower than the risk of severe illness or death caused by new coronary pneumonia, especially for the elderly and other vulnerable groups
    .

    The research team said that it should be noted that these small risks are important but rare, and are comparable to the risks of other vaccines, including vaccines for hepatitis B, cysticercosis, mumps, rubella, and influenza
    .

    Cines and others also wrote in their opinion article that the world's efforts to control the new coronavirus have brought the fastest and most extensive vaccination plan in human history
    .
    Despite its many benefits, it also has potential side effects, including autoimmune reactions
    .

    Cines et al.
    emphasized that when interpreting the findings in the latest study published by Nature-Medicine, it is necessary not only to consider the advantages and limitations of the research itself, but also to consider the broader clinical background and the risks and benefits of vaccination.
    The balance between the two is very important
    .
    "

    This opinion article believes that, in general, the idea that vaccination may induce immune thrombocytopenic purpura is not new, and it is not without precedent in the history of vaccines
    .
    For example, thrombocytopenia is common in children who receive an attenuated measles vaccine
    .
    The risk of ITP is generally mild and will subside within a few weeks or months.
    It is estimated that about 1 case per 40,000 doses of measles-mumps-rubella vaccine, which is only slightly higher than the risk of natural infection
    .

    Cines et al.
    believe that attributing a rare adverse event to a vaccine will exacerbate the phenomenon of "vaccine hesitation" and have an important impact on public health
    .
    "In general, the authors concluded that there is no clear evidence that ITP is related to the first dose of the BNT162b2 vaccine, and the ChAdOx1 vaccine may increase the risk of ITP
    .
    "

    They believe that, at present, the incidence, severity, duration, and response to treatment of ITP after vaccination have not yet been fully determined, and further analysis is needed
    .
    "Nevertheless, the risk of vaccine-induced ITP appears to be much lower than many of the risks associated with COVID-19
    .
    "

    Cines and others pointed out that some large international efforts are still ongoing to continue to evaluate and improve vaccine safety
    .

    Link to the paper: https:// href="/news/sub2.
    aspx?id=3570" target="_blank" style="color:#ba1413">Focus on the new crown pneumonia epidemic

    This article is an English version of an article which is originally in the Chinese language on echemi.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to service@echemi.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

    Contact Us

    The source of this page with content of products and services is from Internet, which doesn't represent ECHEMI's opinion. If you have any queries, please write to service@echemi.com. It will be replied within 5 days.

    Moreover, if you find any instances of plagiarism from the page, please send email to service@echemi.com with relevant evidence.