Omicron BA.4 and BA.5 Subvariants Detected

In more than a dozen countries driving Covid outbreaks across the world, Omicron subvariants BA.4 and BA.5 have been detected, according to the World Health Organization. According to Maria Van Kerkhove WHO’s technical lead on Covid, at least 16 countries have reported about 700 cases of BA.4, while more than 300 cases of BA.5 have been found across at least 17 countries, CNBC reported.

The new sub-variants do not cause more severe infections than the Omicron strain. Still, they appear to be more contagious; Van Kerkhove said during a Q&A on the organization’s social media platforms on Wednesday.

She noted that the WHO is monitoring BA.4 and BA.5 to determine if they will eventually overtake BA.2 as the dominant strain worldwide.

"We don’t know how this variant will behave, how these sub-variants will behave in other countries with a dominant wave of BA.2," Van Kerhkove said. "This is what remains to be seen."

Omicron Subvariants

Last week, the U.K. Health Security Agency report showed that South Africa reported the highest — 395 cases of BA.4 and 134 cases of BA.5 as of May 6.

Other countries that detected the variants include Austria, the U.K., the U.S., and Denmark. The report said that Belgium, Israel, Germany, Italy, Canada, France, the Netherlands, Australia, Botswana, Portugal, Hong Kong, Norway, Pakistan, Spain, and Switzerland had reported the variants.

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The report noted the number of sequences is low, but "the apparent geographic spread suggests that the variant is transmitting successfully."

Van Kerkhove also mentioned that another Omicron subvariant called BA.2.12.1 was detected in 23 countries. She said that there are more than 9,000 reported sequences of the subvariant, most of which had originated from the U.S., the report said. BA.2.12.1 made up about 42.6 percent of all new cases in the U.S. during the week that ended on May 7, according to data from the Centres for Disease Control and Prevention.

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Van Kerkhove said that the higher growth rate of BA.2.12.1 can likely lead to increased transmission globally, but it has shown no difference in hospitalization rates compared to BA.2.

She urged governments worldwide to closely monitor BA.2.12.1, BA.4, BA.5, and other sub-variants that could emerge, emphasizing the need to maintain Covid testing and sequencing.

Source-IANS