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- The current surge in Covid-19 infections in China is believed to be driven by the BF.7 sub-variant of Omicron that is circulating in that country.
What is Mutation?
- Like any other organism, the Covid-19 is also constantly mutating, with some changes in its genetic structure happening in every replication cycle.
- The RNA strand of the virus will replicate and will make mistakes resulting in mutations.
- Most of these mutations are inconsequential and do not alter the overall nature or behaviour of the virus.
- These mutations can introduce important changes, helping the virus to adapt or survive better.
- Three kinds of changes keenly watched are those that
- Increase the ability of the virus to spread faster.
- Cause more severe disease in the infected person.
- Help the virus escape the immune response.
- The INSACOG was set up for this purpose only with an objective to sequence the samples from at least 5% of all the infected cases through a network of laboratories.
- Studying genetic changes in the organism is important for understanding the origin, transmission and impact of the virus on patients.
BF.7
- SARS-CoV-2 Omicron BF.7 is a subvariant of the SARS-CoV-2 Omicron variant.
- Early studies have indicated that it is highly infectious and spreads faster than other variants.
- Common symptoms of the variant are: congestion, sore throat, cough, fatigue and runny nose.
Spread of BF.7
- It is responsible for the current wave of COVID-19 in China. In China, it was firstly reported in Yantai and Shaoguan districts of China in late September 2022.
- Before China, this variant has been making rounds in the USA and Europe since August 2022. BF.7 accounted for more than 5% of US cases and 7.26% of UK cases in October.
Why are covid-19 cases increasing in China?
- Experts believe that it is not the higher transmissibility or immune evasiveness of the BF.7 variant that led to the increase in cases in China, rather an immune-naïve population drove the numbers.
- The vast majority of China’s population has not been infected by the virus and hence has no immunity. Vaccines are not known to prevent infection in very significant ways.
- Thus, when a fast-spreading variant like Omicron does manage to break through the strong defences of the zero-Covid strategy, as it sometimes will, it encounters a vast pool of susceptible people. The virus is able to spread very rapidly after that.
Source: TH
