echemi logo
Product
  • Product
  • Supplier
  • Inquiry
    Home > Biochemistry News > Biotechnology News > What is the reason why the Delta new crown variant that has swept the world is so contagious?

    What is the reason why the Delta new crown variant that has swept the world is so contagious?

    • Last Update: 2021-07-29
    • Source: Internet
    • Author: User
    Search more information of high quality chemicals, good prices and reliable suppliers, visit www.echemi.com

    Recently, the Delta (B.


    ▲The Delta variant (cyan in the picture) has become the main new coronavirus variant circulating in many countries (picture source: nextstrain.


    The immune escape ability of the Delta variant

    The immune escape ability of the Delta variant

    One reason why the Delta variant is highly infectious is that it can evade the neutralizing ability of neutralizing antibodies produced by the immune system


    A study released by Johnson & Johnson also showed that the serum of subjects vaccinated with Ad26.


    However, it is worth mentioning that the data of these studies show that the immune escape ability of the Delta variant is not the strongest among the existing new crown variants


    The Delta variants are faster to copy

    The Delta variants are faster to copy

    A number of recently released studies have shown that an important reason for the highly contagious Delta variant is that it multiplies faster in infected patients, causing patients to release virus particles earlier and release more virus particles


    For example, a recent study published online by the research team of the Guangzhou Centers for Disease Control and Prevention studied the viral load of a series of Delta infection cases found in China after May 21 this year


    Researchers found that among these quarantined people, the average time from the first virus exposure to the PCR test being positive was 4 days, while in the 2020 COVID-19 pandemic, the number of people infected with the virus strain at the time was 6 days.


    Moreover, when using the Ct value of the PCR test to evaluate the new coronavirus load of the patient sample, it was found that the viral load of the patient infected with the Delta variant when the initial PCR test was positive was 1,260 times higher than that of the 2020 virus strain


    ▲Delta variants lead to shorter PCR positive results in infected persons (b, d), and higher viral load in oropharyngeal swab samples (c, lower Ct value) (picture source: reference [1] )

    These data are consistent with the faster proliferation of Delta variants in patients


    The in vitro study published by Professor Gupta's team on bioRxiv also provided more evidence for the strong proliferation ability of Delta variants


    ▲The replication speed of the Delta variant in a variety of in vitro models of human airway exceeds that of the Alpha variant (picture source: reference [2])

    The means to fight against the Delta variant is still in our hands

    The means to fight against the Delta variant is still in our hands

    Dr.


    The faster replication ability of the virus also poses a challenge to the durability of the new crown vaccine


    ▲For slow-replicating viruses, the immune response stimulated for the second time has enough time for the antibody to reach the protective level (a).


    Note: The original text has been deleted

    Reference materials:

    [1] Li et al.


    [2] Mlcochova et al.


    [3] Pollard and Bijker (2021).
    A guide to vaccinology: from basic principles to new developments.
    Nature Immunology, https://doi.
    org/10.
    1038/s41577-020-00479-7

    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.