Over 500 samples of Omicron sub-variant detected in India: Here’s what we know so far of BA.2

Commonly called ‘Stealth Omicron, the new sub-variant reportedly doesn’t show up on RT-PCR tests; experts say one mustn’t panic, but maintain vigilance

FP Staff January 24, 2022 11:54:53 IST
Over 500 samples of Omicron sub-variant detected in India: Here’s what we know so far of BA.2

Representational image. AFP

As the world grapples with the Omicron-driven surge of COVID-19 cases, a recently-discovered sub-variant of the COVID-19 variant is already a cause for concern.

The new mutation of the deadly virus has been discovered in several countries including India.

Here's what we know so far of the latest version, dubbed BA.2.

BA.2 sub-variant

British health authorities have notably identified hundreds of cases of the latest version, dubbed BA.2, while international data suggest it could spread relatively quickly.

The UK Health Security Agency (UKHSA) identified more than 400 cases in Britain in the first 10 days of this month and has indicated the latest variant has been detected in some 40 other countries, accounting for a majority of most recent cases in some nations including India, Denmark and Sweden.

The UKHSA indicated on Friday it had designated the BA.2 sub-lineage as a variant under investigation (VUI) as cases of it were on the increase even if, in Britain, the BA.1 lineage currently remains dominant.

According to research, when the scientists discovered the Omicron variant, they noted that its original strain — the BA.1 — has a mutation in the form of a deletion in the ‘S’ or spike gene which was detected by the PCR tests.

The BA.2 sub-strain, however, does not have the same mutation, due to which it was called ‘stealth Omicron’.

A few experts have claimed that the sub-strain does show up on PCR tests. “BA.2 _is_ detectable by PCR, these news reports are totally wrong. Depending on the PCR test used it may not look like BA.1 (the other Omicron). But it will still give a positive result. Frustrating to see falsehood about non-detectability still around,” Cornelius Roemer, a computational biologist at Switzerland's University of Basel, said on Twitter.

Where is it prevalent?

Commonly called 'stealth Omicron', cases of the sub-variant have been detected in UK and Denmark, Sweden, Norway, and India.

The situation is particularly bad in Denmark where BA.2 has gone from accounting 20 per cent of the cases to 45 per cent between late December and mid-January. According to Fortune, Denmark has been recording over 30,000 new cases per day this week, 10 times more cases than peaks in previous waves.

But Danish authorities also urged the public to not read too much into BA.2's rise at this point.

“Initial analysis shows no differences in hospitalisations for BA.2 compared to BA.1,” Denmark’s Statens Serum Institut, a government-run infectious disease research center, said in a statement on Thursday. “It is expected that vaccines also have an effect against severe illness upon BA.2 infection.”

Situation in India
According to a Hindustan Times report dated 23 January, India has reported 530 samples of Omicron sub-variant.

On Sunday, the INSACOG in its latest bulletin, said while most Omicron cases in the country so far have been asymptomatic or mild, hospitalisations and ICU cases have increased in the current wave and the threat level remains unchanged.

"Omicron is now in community transmission in India and has become dominant in multiple metros, where new cases have been rising exponentially. BA.2 lineage is in a substantial fraction in India and S gene dropout based screening is thus likely to give high false negatives," the INSACOG said.

"The recently reported B.1.640.2 lineage is being monitored. There is no evidence of rapid spread and while it has features of immune escape, it is currently not a variant of concern. So far, no case has been detected in India," the INSACOG further added.

Experts speak

Scientists and medical experts have been put on high alert following the detection of the sub-variant and are now trying to determine how its emergence could affect future pandemic spread.

Dr Meera Chand, COVID-19 Incident Director at UKHSA, said the nature of viruses is to evolve and mutate so the emergence of new variants is expected as the pandemic goes on, reported Reuters.

“So far, there is insufficient evidence to determine whether BA.2 causes more severe illness than Omicron BA.1, but data is limited and UKHSA continues to investigate,” Chand said.

French epidemiologist Antoine Flahault was quoted as telling AFP, "What surprised us is the rapidity with which this sub-variant, which has been circulating to a great extent in Asia, has taken hold in Denmark."

"France expected a spike in contaminations in mid-January. It didn’t happen and perhaps that is due to this sub-variant, which seems very transmissible but not more virulent” than BA.1," he observed.

“What interests us is if this [sub-variant] possesses different characteristics from BA.1 in terms of contagiousness and severity," France’s public health agency said on Friday.

Flahault, director of the University of Geneva’s Institute of Global Health, says the watchword is not panic but 'vigilance' as for now we have the impression [BA.2 case] severity is comparable to classic variant Omicron cases.

With inputs from agencies

Read all the Latest News, Trending NewsCricket News, Bollywood News,
India News and Entertainment News here. Follow us on Facebook, Twitter and Instagram.

Updated Date:

also read

COVID-19: NRI on Gujarat visit tests positive for Omicron sub-variant BA.5
Health

COVID-19: NRI on Gujarat visit tests positive for Omicron sub-variant BA.5

The man, who lives in South Africa, had on 1 May tested positive for the coronavirus after he arrived here to meet his parents

COVID 19: INSACOG confirms first case of BA.4, BA.5 Omicron subvariants in India
Health

COVID 19: INSACOG confirms first case of BA.4, BA.5 Omicron subvariants in India

BA.4 and BA.5 are subvariants of the Omicron variant circulating globally. These were reported first from South Africa earlier this year and are now reported from several other countries

Saudi Arabia bans travel to 16 countries including India over new COVID outbreaks
World

Saudi Arabia bans travel to 16 countries including India over new COVID outbreaks

The sixteen countries where the citizens of Saudi Arabia are banned to travel apart from India include Lebanon, Syria, Turkey, Iran, Afghanistan, Yemen, Somalia, Ethiopia, the Democratic Republic of the Congo, Libya, Indonesia, Vietnam, Armenia, Belarus, and Venezuela