Keeping track of COVID variants

16 April 2021 10:14 am Views - 160

 

One of the main concerns with regards to COVID-19 is the fact that the virus mutates, giving rise to new variants with concerning features. Some can easily spread while others have several mutations. The most well-known variants are variants that were first discovered in the United Kingdom and South Africa. Recently, a variant from Brazil has received attention. Each variant arose independently and all have unique mutations as well as mutations in common.

 

United Kingdom variant

• First emerged in the UK in September 2020.
• Has an unusually large number of mutations.
• Preliminary evidence suggests that people infected with this variant have a higher viral load and that the variant spreads more rapidly.
• New evidence suggests this variant may cause a small increase in disease severity.
• The variant continues to increase in prevalence in the United States.
• Studies suggest the UK variant doesn’t have a major impact on vaccine efficacy.
• Several countries, including the U.S., have reported the variant since December 2020.

 

South Africa variant

• First emerged in October 2020.
• Spreads more easily and quickly than other variants.
• There is no evidence at this time that it causes more severe illness or increases risk of death.
• Very few cases of the variant have been found in the U.S.
• Studies are currently testing whether today’s COVID-19 vaccines work just as well against this variant.
• Lab studies suggest the Moderna and Pfizer vaccines may have slightly reduced efficacy against this variant.
• Moderna is currently testing a booster shot designed specifically against the South Africa variant and Pfizer is expected to begin similar studies shortly.
• Even if these vaccines don’t work as well at preventing mild-to-moderate disease, protection against severe disease and death is expected to remain strong.
• A Phase 3 clinical trial showed the Johnson & Johnson vaccine did not work quite as well at preventing asymptomatic disease. However, the vaccine was just as effective against hospitalization and death.

 

Brazilian variant

• First emerged in January 2021.
• It shares some critical mutations with the South Africa variant.
• The variant was identified in the U.S. at the end of January, 2021; very few cases are confirmed.
• Studies are currently testing vaccine efficacy, but it doesn’t appear to have a major impact.
• Johnson & Johnson conducted part of its vaccine trial in Brazil and reported no issues with vaccine efficacy.
• Pfizer and Moderna believe their vaccines retain high efficacy against this variant.

 

Denmark variant 
Recently, three people with Denmark lineage of COVID-19 was identified from Colombo city limits. In June 2020, several COVID cases were reported from Denmark with SARS-COV-2 variants associated with farmed minks. Preliminary findings indicate that this particular mink-associated variant identified in both minks 12 human cases has moderately decreased sensitivity to neutralizing antibodies.

 

‘Double mutant’ COVID strain from California 
Stanford University researchers have identified five new cases of a “double mutant” Covid-19 strain that was recently discovered in the San Francisco Bay Area. Doctors suspect it could be more contagious than earlier strains and may be resistant to existing vaccines.The new variant originated in India where it’s credited with a recent 55% surge in cases in the state of Maharashtra, home to Mumbai, after months of declining cases.

It contains two key mutations, which scientists call E484Q and L452R, that have been found separately in other variants but not together in a single strain, according to Dr. Benjamin Pinsky, medical director of Stanford’s clinical virology laboratory, which discovered the new variant in the U.S.  Medical experts claim that the double mutant variant has known mutations in the scariest place to have a mutation — the receptor binding domain, where the virus uses to latch on to cells in our bodies in order to enter.
Source : Johns Hopkins Medicine