Here’s what we know about BA.2, the sister of Omicron

Agencies
February 3, 2022

Cases of the SARS-CoV-2 variant Omicron have escalated globally over the past two months, with many countries experiencing peaks higher than previous variants.

Now we’re seeing cases of a sub-variant of Omicron, known as BA.2, emerge in Australia and more than 50 countries.

Rather than a daughter of the Omicron variant BA.1 (or B.1.1.529), it’s more helpful to think of BA.2 as Omicron’s sister.

Remind me, what is a variant?

Viruses, and particularly RNA viruses such as SARS-CoV-2, make lots of mistakes when they reproduce. They can’t correct these mistakes, so they have a relatively high rate of errors, or mutations, and are constantly evolving.

When the genetic code of a virus changes as a result of these mutations, it’s referred to as a variant.

Omicron is a “highly divergent” variant, having accumulated more than 30 mutations in the spike protein. This has reduced the protection of antibodies from both prior infection and vaccination, and increased transmissibility.

When do health authorities worry about a new variant?

If changes in the genetic code are thought to have the potential to impact properties of the virus that make it more harmful, and there’s significant transmission in multiple countries, it will be deemed a “variant of interest”.

If a variant of interest is then shown to be more infectious, evade protection from vaccination or previous infection, and/or impact the performance of tests or treatments, it is labelled a “variant of concern”.

The World Health Organization (WHO) classified Omicron a variant of concern on November 26 because of its potential to cause higher reinfection rates, increased transmissibility and reduced vaccine protection.

What is the Omicron lineage?

A lineage, or sub-variant, is a genetically closely related group of virus variants derived from a common ancestor.

The Omicron variant comprises three sub-lineages: B.1.1.529 or BA.1, BA.2 and BA.3.

While the WHO has not given BA.2 a separate classification, the United Kingdom has labelled BA.2 a variant “under investigation”. So not yet a variant of interest or concern, based on WHO definitions, but one that is being watched closely.

This is not the first variant to have sub-lineages. Late last year, Delta “plus” or AY.4.2 was reported widely, then Omicron came along.

What’s different about BA.2?

While the first sequences of BA.2 were submitted from the Philippines – and we have now seen thousands of cases, including in the United States, the UK and some in Australia – its origin is still unknown.

The exact properties of BA.2 are also still being investigated. While there is no evidence so far that it causes more severe disease, scientists do have some specific concerns.

1. It’s harder to differentiate

A marker that helped differentiate Omicron (BA.1) from other SARS-CoV-2 variants on PCR tests is the absence of the the S gene, known as “S gene target failure”. But this is not the case for BA.2.

The inability to detect this lineage in this way has led some to label it the “stealth sub-variant”.

But it doesn’t mean we can’t diagnose BA.2 with PCR tests. It just means when someone tests positive for SARS-CoV-2, it will take us a little longer to know which variant is responsible, through genome sequencing. This was the case with previous variants.

2. It may be more infectious

Perhaps most concerning is emerging evidence BA.2 may be more infectious than the original Omicron, BA.1.

A preliminary study from Denmark, where BA.2 has largely replaced BA.1, suggests BA.2 increases unvaccinated people’s susceptibility of infection by just over two times when compared to BA.1.

The researchers suggest fully vaccinated people are 2.5 times more susceptible to BA.2 than BA.1, and those who were booster vaccinated are nearly three times more susceptible.

The study examined more than 2,000 primary household cases of BA.2 to determine the number of cases that arose during a seven-day follow up period.

The researchers also estimated the secondary attack rate (basically, the probability infection occurs) to be 29 per cent for households infected with BA.1 versus 39 per cent for those infected with BA.2.

This Danish study is still a preprint, meaning it’s yet to be checked by independent scientists, so more research is needed to confirm if BA.2 is truly more infectious than BA.1.

We’re likely to see new variants We should expect new variants, sub-variants and lineages to continue to emerge. With such high levels of transmission, the virus has abundant opportunity to reproduce and for errors or mutations to continue to arise.

The way to address this, of course, is to try to slow transmission and reduce the susceptible pool of hosts in which the virus can freely replicate.

Strategies such as social distancing and mask-wearing, as well as increasing vaccination rates globally, will slow the emergence of new variants and lineages. 

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News Network
March 10,2023

Hassan, Mar 10: Seventy-eight-year-old Hiregowda of Alur taluk, Hassan district, became the first victim of H3N2 virus infection in Karnataka, according to District Health Officer Dr Shivaswamy.

Hiregowda was suffering from fever, throat pain, cough, and other symptoms for a few days in February. His throat swab and samples were sent to the lab for testing. But he succumbed on March 1.

Health screening is being conducted in and around the villages. Those suffering from any symptoms of viral fever and infection have been subjected to further screening. The throat swabs have been sent for testing, Shivaswamy said.

Six cases of the virus have been identified so far in Hassan district. The virus is primarily affecting children below 15 years and senior citizens. They have been advised to be cautious and undergo medical checkups in case of any symptoms, the DHO said.

The health department has directed its personnel to keep a eye on those above 60 years and suffering from diabetes and other comorbidities.

The department has been directed to conduct medical screening for the next 14 days, around the farmhouse, where Hiregowda was living and measures are being taken, the DHO said.

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News Network
March 8,2023

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Two American lawmakers say Ukraine is pushing the United States to provide it with banned cluster bombs to drop them on Russian forces from drones.

Jason Crow and Adam Smith who serve on the House of Representatives Armed Services Committee said Kiev has urged members of Congress to press the White House to approve the weapons shipment, Reuters reported on Wednesday.

Cluster bombs include anti-armor bomblets Ukraine plans to use against Russian forces by drones. That is in addition to the 155-millimeter artillery cluster shells Ukraine has already requested.

Cluster munitions, banned by more than 120 countries, normally release large numbers of smaller bomblets that can kill indiscriminately over a wide area, threatening civilians.

The lawmakers said Ukraine is seeking the MK-20, an air-delivered cluster bomb, to release its individual explosives from drones.

They said Ukrainian officials called on American lawmakers at last month's Munich Security Conference to press for White House approval.

Ukraine hopes cluster bombs will give it an edge in the fight against Russian troops in eastern Ukraine.

Republican Senator Lindsey Graham also participated in last month's conference. The senator who is considered the main supporter of the US -industrial complex in Congress confirmed that Ukrainian officials in Munich called for cluster munitions. He said he would support the request.

"This is a war where (the Ukrainians) are outmanned," Graham told Reuters. "And cluster munitions really are pretty lethal to mass formations as well as armor. In the areas where they are going to use this stuff there are no civilians."

So far, the Biden administration has refrained from officially sending any cluster munitions to Ukraine. However, even though the export of such weapons has been banned by Congress, media outlets such as Politico have suggested that US President Joe Biden and even his Secretary of State Antony Blinken could potentially override this ban.

An American adviser to the Ukrainian military has also called on Washington to send Kiev forces cluster munitions to fight Russia.

Dan Rice said in December that the US “really needs to” supply Kiev’s forces with cluster bombs to increase “base lethality” and “win the war” against Russia.

In October, Russian officials revealed that the Kiev forces had used cluster munitions to arm a US-made HIMARS rocket launcher to strike a river crossing in Kherson, which killed four civilians, including a journalist. Kiev, however, has denied responsibility for the attacks.

In this regard, a former CIA contractor told Press TV that the Ukrainian forces were already using banned cluster munitions and other illegal weapons, so Washington’s decision to provide Kiev with more lethal ammunition made no difference.

Cluster bombs are banned under the Convention on Cluster Munitions (CCM), an international treaty that addresses the humanitarian consequences and unacceptable harm caused to civilians by cluster munitions through a categorical prohibition and a framework for action. The weapons can contain dozens of smaller bomblets, dispersing over vast areas, often killing and maiming civilians long after they are dropped.

The convention bans all use, production, transfer and stockpiling of cluster bombs. More than 100 countries have signed the treaty, but the United States has not. 

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News Network
March 21,2023

shyaranya.jpg

Kasaragod, Mar 21: A teenage girl student was found dead at her residence under suspicious circumstances at Illathingal, Bantukka Malamkund in Kasaragod district. 

The deceased is KV Sharanya (17), a plus two student of a government higher secondary school. She was the daughter of Babu and Sujata couple. 

The incident came to light when her mother Sujata returned home from work last evening. 

The girl was preparing for the Plus Two exams. It is learnt that she was studying when her mother left home for work. After returning home, the mother peaked into daughter’s bedroom to find out what the latter was doing. 

To her horror, she witnessed her daughter’s dead body. It is learnt that the body was in sitting position on the bed hanging from the rope attached to the wall in the bedroom. The door of the room was locked from outside.

The family members suspect foul play in Sharanya’s death, as there was no situation to commit suicide. The death occurred when no one was at home. Police have sealed the house as the death is suspicious.

The body was taken to Kannur Pariyaram Medical College for post-mortem. Jurisdictional Bedakam police have registered a case of unnatural death.

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