BA.4.6 now accounts for more than 9% of recent cases across the US, according to the Centers for Disease Control and Prevention. Several other countries have also identified the variant.
The COVID-19 virus is like any other virus: it mutates and changes over time. There are times when these changes are for the better, and sometimes when they are for the worse.
There are times when they make the virus less deadly, while there are times when they make it more transmissible. The UK and the rest of the world must understand these changes to find a way through the viral landscape.
Omicron BA.4.6 is the latest mutation to catch the attention of the UKHSA (the United Kingdom Health Security Agency). A technical briefing published earlier this month by the UKHSA stated: ”
Omicron sub-lineage BA.4.6 was identified as part of horizon scanning on 15 August 2022.”. On 1 September 2022, BA.4.6 was designated as variant V-22SEP-01.
Earlier this summer, BA.4.6, along with BA.5, began spreading through the UK as a sub-lineage of BA.4. BA.5 has become the dominant variant, but BA.4 remains.
This is evidenced by BA.4.6, which has now spread to the UK. Around three percent of “sequences in the week beginning 14th August 2022” were related to it, according to the UKHSA.
As of the 5th of September, the variant had a growth rate of 36 percent “relative to BA5, the dominant lineage in England”. Therefore, Omicron hasn’t completed its work in the UK yet.
The main symptoms of Omicron BA.4.6, the new variant, are as follows:
COVID-19 is so new that it is not yet known if it causes any symptoms that differentiate it from Omicron BA.5.
What is known is how much it has changed since it first emerged nearly three years ago.
Initially, the pandemic was characterized by a loss of smell and taste, a continuous cough, and fatigue.
Now the main symptoms are as follows:
• Sore throat
• Blocked nose
• Cough (with no phlegm)
• Runny nose.
As the number of cases of Omicron BA.4.6 continues to rise, it could become a bigger problem.
Severity, infectiousness, and immune evasion
In general, omicron infections cause less serious illness, and we’ve seen fewer deaths with omicron.
This should also apply to BA.4.6. There have been no reports that this variant causes more severe symptoms.
Furthermore, we know that omicron subvariants tend to be more transmissible than previous variants.
BA.4.6 appears to be even more adept at evading the immune system than BA.5, the dominant variant.
However, other emerging data supports this information, despite it being based on a preprint (a study that has not yet been peer-reviewed).
UKHSA’s briefing suggests BA.4.6 has a relative fitness advantage of 6.55% over BA.5 in England. BA.4.6 replicates and grows faster in the early stages of infection than BA.5.
A relative fitness advantage of BA.4.6 is considerably smaller than that of BA.5 over BA.2, which ranged from 45% to 55%.
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