Thread by @FLAHAULT

1/9 - “Since Omicron emerged in late 2021, it has rapidly evolved into multiple subvariants. One subvariant, #BF7, has recently been identified as the main variant spreading in Beijing, and is contributing to a wider surge of #COVID19 infections in China.”
livescience.com/covid-what-we-…

2/9 - “But what is this new variant, and should we be worried? Although reports from China about this variant's characteristics are concerning, it doesn't appear to be growing too much elsewhere in the world.”

3/9 - “#BF7 is believed to have an R0, or basic reproduction number, of 10 to 18.6. This means an infected person will transmit the virus to an average of 10 to 18.6 other people. Research has shown omicron has an average R0 of 5.08.”

4/9 - “The high transmission rate of #BF7, taken with the risk of hidden spread due to the many asymptomatic carriers, is understood to be causing significant difficulty in controlling the epidemic in China.”

5/9 - “The symptoms of an infection with #BF7 are similar to those associated with other omicron subvariants, primarily upper respiratory symptoms. Patients may have a fever, cough, sore throat, runny nose and fatigue, among other symptoms…”

6/9 - “A minority of people can also experience gastrointestinal symptoms like vomiting and diarrhoea.
#BF7 may well cause more serious illness in people with weaker immune systems.”

7/9 - “A recent study examined the neutralisation of #BF7 in sera from triple-vaccinated healthcare workers, as well as patients infected during the omicron BA.1 and BA.5 waves of the pandemic. BF.7 was resistant to neutralisation, driven partly by the R346T mutation.”

8/9 - “Despite #BF7's immune-evasive characteristics, and worrying signs about its growth in China, the variant seems to be remaining fairly steady elsewhere. For example, in the U.S. it was estimated to account for 5.7% of infections up to Dec 10, down from 6.6% the week prior.”

9/9 - “The emergence of #BF7 and other new variants is concerning. But vaccination is still the best weapon we have to fight #COVID19. And the approval by drugs regulator of bivalent boosters, which target omicron alongside the original strain of #SARSCoV2, is very promising.”