The Omicron variant, a highly contagious variation of the SARS-CoV-2 virus, whose most prevalent type is classified as BA.1, now reportedly accounts for practically all Covid-19 infections worldwide. However, despite significant spikes, cases have already peaked across some nations.

This is not the end though, as scientists are currently tracking an increase in infections caused by BA.2, a relatively close subvariant of BA.1 that is beginning to outpace it in European and Asian countries.

As of January 25, BA.1 was responsible for a total of 98.8% of cases brought to GISAID, the database to track the public viruses. But, according to the World Health Organization (WHO), notable spikes in the variant termed as BA.2 have been reported in various nations.

BA.1.1.529 as well as BA.3. are two more subvariants listed by the WHO under the Omicron category, along with BA.1 and BA.2. Genetically, they are all closely linked, but each have variations that could change how they act.

Fred Hutchinson Cancer Center computational virologist, Trevor Bedford, who has been monitoring SARS-CoV-2 mutations, Tweeted last week, that BA.2 accounts for around 82% of cases in Denmark, 8% in USA, and 9% in the United Kingdom. The estimates are based on Bedford’s analysis of the sequencing data obtained from the GISAID database combined with the case counts received from the University of Oxford's Our World in Data project.

The BA.1 mutant of Omicron was a little easier to monitor than previous varieties since BA.1 lacks one of the three target genes utilized in a standard PCR test. By default, cases that showed this pattern were believed to be caused by the BA.1.

However, the BA.2 subvariant, termed as a ‘stealth’ subvariant, lacks the very same lacking target gene. Alternatively, researchers are monitoring the variant by tracking virus genomes numbers posted on public databases like GISAID, just as they have with previous versions like Delta.

Experts say that coronavirus personal test kits can identify the BA.2 infection but they cannot be sure which one is the cause of the infection.

According to some early studies, BA.2 may be considerably more communicable than BA.1, which is already exceedingly communicable, although there is no indication that it is much more likely to minimize vaccine protection.

Source credit: https://www.geo.tv/latest/396098-scientists-on-alert-over-rising-cases-caused-by-omicron-cousin-ba2