The COVID-19 delta variant is now in Australia, and this time around things might not be the same.
The virus behind the COVID-19 pandemic is mutating as it spreads across millions of human hosts, and the so-called Delta variant is now amongst us. This new form of the COVID-19 virus is officially labelled “a variant of concern”, as it is thought to be more infectious.
Here are the key details you need to know about this variant.
Name and origin: the official name of the Delta variant is B.1.617 and it was first detected in December 2020, in India, where it is thought to have been the key variant behind India’s second wave of infections, back in April of this year, when more than 161,000 cases were being reported per day.
What is a variant of concern? According to the website from the Centers of Disease Control and Prevention, in the USA, a variant of concern is defined as: “A variant for which there is evidence of an increase in transmissibility, more severe disease (e.g., increased hospitalizations or deaths), significant reduction in neutralization by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures.”
Other categories you should know about are:
“Variant of Interest”, defined as: “A variant with specific genetic markers that have been associated with changes to receptor binding, reduced neutralization by antibodies generated against previous infection or vaccination, reduced efficacy of treatments, potential diagnostic impact, or predicted increase in transmissibility or disease severity.”
and
“Variant of High Consequence”, defined as: “A variant of high consequence has clear evidence that prevention measures or medical countermeasures (MCMs) have significantly reduced effectiveness relative to previously circulating variants.”.
The delta variant is the fourth variant designated as being of global concern. The three other variants of concern are the B.1.1.7 or Alpha variant, first reported in the United Kingdom, the B.1.351 or Beta strain, from South Africa and P1 or Gamma strain, from Brazil and Japan.
To learn more about all the COVID-19 variants, see the website from the European Centre for Disease Prevention and Control.
About the Delta variant – This new variant is known to host several new mutations in its genome, particularly mutations in the outer spike protein, which affects the transmissibility of the virus. The B.1.617 or Delta variant also has several sub-variants, among which the B.1.617.2 subvariant seems to spread more efficiently than the original virus. A recent pre-print report also suggest that re-infection might be more common with this variant. However, further research is needed to confirm this finding or to understand if the Delta variant is more pathogenic.
‘This particular Delta variant is faster. It is fitter. It will pick off the more vulnerable more efficiently than previous variants, and therefore if there are people left without vaccination, they remain even at further risk,’ Dr Mike Ryan, Executive Director of the WHO’s Health Emergencies Program, said in a RACGP news report.
Are Vaccines effective against the Delta variant? The short answer is yes, and all Australians should get vaccinated as soon as possible. However, we don’t know exactly how effective our currently available vaccines are against this variant. According to one study, the effectiveness of current vaccines might be lower, compared to the original COVID-19 strand.
However, the findings of this study as still preliminary and have not been peer-reviewed, so more time and research are needed to reach a conclusion. The figure above was sourced from a recent article from The Conversation, found here.