Britain announced surveillance of an omicron subvariant. But there is a problem, because the variant is difficult to detect.
London – “Since the beginning of January 2022, Omikron has been the dominant variant in Germany,” reports the RKI*. At the same time, the number of infections in Germany is increasing significantly. On Saturday (January 22), 135,461 new infections were reported. Incidence* climbed to a record high of 772.7. The 7-day value has never been this high since the beginning of the pandemic. But there doesn’t seem to be just Omicron. In addition to the highly contagious variant, there is also a sub-form circulating. Great Britain now wants to monitor this more closely. What distinguishes them from Omicron itself?
BA.2: UK monitors omicron subvariant – It could be even more contagious
BA.2: this is the name of the sub-variant of omicron. As general practitioner Dr. Christoph Specht explained in the RTL interview, “BA.2 has 17 mutations that distinguish it from the previous omicron variant. That’s quite a lot.” However, it is more similar to Omikron than the other variants Alpha, Beta or Delta. The British health authority has now classified the variant as a “variant under observation”. Typically, variants that may eventually be called “variants of concern” are first observed and further analyzed.
The reason for the classification is the transferability of BA.2. There is a suspicion that BA.2 could be even easier to transfer than the original form of the omicron variant, which is also called BA.1. The first analysts suggested this assumption, but further analyzes are necessary, it is said. “We really know very little about it,” says Specht.
According to the authority, 426 cases of BA.2 are known in Great Britain to date. The sub-variant has also appeared in other European countries. Cases from Denmark, India, Sweden and Singapore are also known – most of them in Denmark with more than 6400 cases. However, it is unclear where the variant first appeared.
BA.2: Omicron subvariant cannot be identified with the PCR test – genome analysis required
BA.2, the “stealth mutation*”? Researchers in Great Britain had already discovered the variant in November. But recognizing BA.2 does not seem to be easy. It can be identified as a coronavirus using a PCR test*, but cannot be distinguished from other variants of the coronavirus. A specific genetic change is absent from this subvariant that would allow PCR testing to identify it as an omicron mutation. Specifically, Omicron does not have an S gene, unlike Delta. “If you did a normal PCR test, you could say: if this S gene was there, then it was delta. If the S gene wasn’t there, then it definitely wasn’t Delta,” says Specht. This elimination process does not work with BA.2. Instead, a complex genome analysis is required for identification. Virologist Drosten also warned of a possible recombination of delta and omicron – a more dangerous variant? (chd/dpa) *Merkur.de is an offer from IPPEN.MEDIA.
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