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
May 14,2022

In response to the cold-blooded killing of journalist Shireen Abu Akleh by Israeli regime forces, the Palestinian resistance movement Hamas has called for a unified command against the occupying regime.

In his remarks late on Friday, Ismail Haniyeh, the head of the Gaza-based resistance movement's political bureau, urged the “speedy formation” of the command to lead the struggle against Israel.

The call came two days after 51-year-old Abu Akleh was brutally murdered while covering an Israeli military raid on the Jenin refugee camp in the northern part of the occupied West Bank.

The long-time Al Jazeera Arabic journalist, who shot to fame while covering the second Palestinian Intifada between 2000 and 2005, was accompanying a group of local journalists when she was targeted.

Haniyeh said the Palestinian liberation struggle is going through a "new stage," which demands the adoption of "incisive and strategic decisions".

He said the unified command will be tasked with directing the resistance against the apartheid regime.

Formation of the unified front is indispensable in the light of the regime's "bestiality," which manifested itself in the "assassination of the daughter of Palestine," Haniyeh said, referring to Abu Akleh.

The Hamas leader said Palestinians need to get their act together in the face of Tel Aviv's unbridled aggression, advocating unity between different Palestinian political groups.

He cited examples of Israeli aggression such as the increase in settlement construction activities across the occupied territories, assaulting Palestinian worshippers at the al-Aqsa Mosque compound in the holy occupied city of al-Quds, the longstanding and crippling siege of Gaza, detention of thousands of Palestinians, and denying them the right to return to their homeland.

Haniyeh called on the West Bank-headquartered Palestinian Authority (PA) to end its cooperation with the regime in Tel Aviv and scrap the so-called Oslo Accords, which were signed in 1993 and marked the first time the Israeli regime and the Palestine Liberation Organization (PLO) recognized each other.

The Oslo Accords were signed in the White House but named after Norway’s capital city, where the secret back-channel dialogue took place.

The Hamas leader urged the PA to withdraw its "recognition of Israel," stop its "security cooperation" with Tel Aviv, "and concentrate on the resistance's comprehensive plan for confronting the occupier."

Pertinently, it came on the eve of Nakba Day, (the Day of Catastrophe), when in 1948 hundreds of thousands of Palestinians were forcibly evicted from their homeland and Israel came into existence as an illegal and illegitimate entity.

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News Network
May 16,2022

People who are vaccinated and then get infected with Omicron may be primed to overcome a broad range of coronavirus variants, early research suggests.  

A pair of studies showed that infection produced even better immune responses than a booster shot in vaccinated patients. Teams from Covid-19 vaccine maker BioNTech SE and the University of Washington posted the results on preprint server bioRxiv in recent weeks.

The findings offer a reassuring sign that the millions of vaccinated people who’ve caught Omicron probably won’t become seriously ill from another variant soon -- even though the research needs to be confirmed, especially by real-world evidence. 

“We should think about breakthrough infections as essentially equivalent to another dose of vaccine,” said John Wherry, a professor and director of the Institute for Immunology at the University of Pennsylvania who wasn’t involved in the research but reviewed the BioNTech study. That could mean that if someone had Covid recently, they could wait before getting another booster shot, according to Wherry. 

Alexandra Walls, a principal scientist at the University of Washington who authored one of the studies, cautioned that people shouldn’t seek out infections in response to the findings.

The data comes as Omicron continues to fuel outbreaks around the world, most notably in China, where residents of Shanghai have endured almost six weeks of lockdown. Waves of new variants are coming more quickly in part because Omicron is so transmissible, giving it ample opportunity to spread and mutate as countries drop restrictions, said Sam Fazeli, an analyst with Bloomberg Intelligence. Meanwhile, regulators are weighing whether Covid vaccines should be updated to target Omicron.

BioNTech’s team argued that the data indicate that offering people an Omicron-adapted booster shot may be more beneficial than multiple ones with the original vaccines.

The Washington research, conducted together with Vir Biotechnology Inc., looked at blood samples from people who had been infected, and then had two or three doses of vaccine, as well as those who’d caught the delta and Omicron variants after two or three doses; others still had been vaccinated and boosted but never caught Covid. A final group had only been infected with Omicron and never vaccinated.

One part of the study zeroed in on antibodies, the protective proteins tailored to recognise and neutralise invaders. It showed vaccinated people who’d caught Omicron had antibodies that outperformed the others. They were even capable of recognizing and attacking the very different delta variants. 

“That indicates that we are at the point where we may want to consider having a different vaccine to boost people,” said David Veesler, an assistant professor at the University of Washington, who led the research. The scientists were also able to identify antibodies in the nasal mucous of these patients, which could help them neutralise the virus as soon as it enters the body. 

Nasal sprays are poised to be the next weapon for fighting Covid

Both the Washington and BioNTech studies also looked at another piece of the immune system: B cells, a type of white blood cell that can kick in to produce a burst of fresh antibodies if they recognise a pathogen. People who’d had an Omicron breakthrough infection had a broader response from these useful cells than those who’d had a booster shot but no infection, the BioNTech team found. 

Crucially, the Washington team also found that the broad response was missing in unvaccinated people who had caught Omicron as their first exposure to the virus. This “would be a problem if a new variant that is significantly different emerged,” Veesler said. 

There’s no guarantee that future mutations will be as mild as Omicron, and the pandemic’s future is hard to predict since it depends not just on immunity in the population, but also on how much the virus mutates. 

Other researchers who reviewed the studies said the findings match up with the growing body of evidence for an immune boost from exposure to different virus variants via vaccination and infection. Scientists have also shown broad immune responses in people who caught delta after getting their shots. 

“Maybe this is an indication that an updated booster might be a good idea,” said Theodora Hatziioannou, a virologist at The Rockefeller University who helped lead a team that looked at breakthrough infections in a group of vaccinated people in New York City. 

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Agencies
May 10,2022

Colombo, May 10: Sri Lanka's former prime minister Mahinda Rajapaksa is facing calls for his arrest from Opposition politicians for inciting violence against peaceful anti-government protesters that claimed at least eight lives, left over 200 people injured and saw arson attacks on the homes of several politicians.

Mahinda Rajapaksa, 76, resigned as Sri Lankan Prime Minister on Monday amid unprecedented economic turmoil, hours after his supporters attacked anti-government protesters, prompting authorities to impose a nationwide curfew and deploy Army troops in the capital.

The resignation of the prime minister has automatically annulled the Cabinet and the country is currently being run by his younger brother and President Gotabaya Rajapaksa.

Mahinda Rajapaksa has been accused by the Opposition of inciting the ruling party mobs to attack peaceful protesters by making a defiant speech while addressing several thousands of his supporters to deflect calls for his resignation.

“Rajapaksa (Mahinda) must be arrested and brought before the law," M A Sumanthiran, the main Tamil legislator, said in a message.

The same sentiments were expressed by former President Maithripala Sirisena and the main Opposition Samagi Jana Balawegaya party's leader Ranjith Madduma Bandara.

“He must be arrested for encouraging violence. There was no reason to attack the peaceful protesters," Sirisena said.

At least eight people were killed in the violence. The Colombo national hospital said at least 217 people had been admitted for treatment.

One of the protesters who had been brutally assaulted by the Rajapaksa supporters remains in a very critical condition.

Mahinda Rajapaksa later resigned, saying he was making way for his brother president Gotabaya Rajapaksa to set up an all-party interim government.

There were reports from all parts of the island of arson attacks on the homes of ruling party politicians, including on the ancestral house of the Rajapaksa family in the deep southern district of Hambantota.

Meanwhile, Mahinda Rajapaksa vacated the Temple Trees, the official residence of the prime minister, Tuesday morning, according to media reports.

The police on Monday used tear gas and fired in the air to stop a mob which was trying to break into Temple Trees, the office cum residence of the prime minister.

An all-island curfew, which was scheduled to be lifted on Tuesday, was extended last night until Wednesday as arson attacks were reported from most parts of the country.

Army chief General Shavendra Silva called for calm and said the necessary action would be taken to maintain law and order.

In the current state of emergency, the troops are given extensive powers to arrest people.

The Opposition parties urged the reconvening of Parliament before the scheduled date of May 17.

Speaker Mahinda Yapa Abeywardena also requested the President to immediately summon Parliament.

The trade unions announced that they would launch a continuous strike from Tuesday to protest against the government-backed crackdown on the peaceful protests.

The violence occurred as pressure mounted on the embattled government led by President Gotabaya to form an interim administration to overcome the worst economic crisis facing the country.

Sri Lanka is currently in the throes of unprecedented economic turmoil since its independence from Britain in 1948. The crisis is caused in part by a lack of foreign currency, which has meant that the country cannot afford to pay for imports of staple foods and fuel, leading to acute shortages and very high prices.

Thousands of demonstrators have hit the streets across Sri Lanka since April 9 seeking the resignation of President Gotabaya and Prime Minister Mahinda, as the government ran out of money for vital imports; prices of essential commodities have skyrocketed and there are acute shortages in fuel, medicines and electricity supply.

In a special Cabinet meeting on Friday, President Gotabaya Rajapaksa declared a state of emergency with effect from Friday midnight. This is the second time that an emergency was declared in Sri Lanka in just over a month as the island nation was in the grip of the worst economic crisis.

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