Covid-19, what the scientists say about it?



Mansura Chameliy, Staff Correspondent, Barta24.com
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Coronaviruses have been causing problems for humanity for a long time. Several versions are known to trigger common colds and more recently two types have set off outbreaks of deadly illnesses: severe acute respiratory syndrome (Sars) and Middle East respiratory syndrome (Mers).

But their impact has been mild compared with the global havoc unleashed by the coronavirus that is causing the Covid-19 pandemic. In only a few months it has triggered lockdowns in dozens of nations and claimed more than 1 lakh lives. And the disease continues to spread.

That is an extraordinary achievement for a spiky ball of genetic material coated in fatty chemicals called lipids, and which measures 80 billionths of a metre in diameter. Humanity has been brought low by a very humble assailant.

On the other hand, our knowledge about the Sars-CoV-2, the virus that causes Covid-19, is also remarkable. This was an organism unknown to science five months ago. Today it is the subject of study on an unprecedented scale. Vaccine projects proliferate, antiviral drug trials have been launched and new diagnostic tests are appearing.

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The questions are therefore straightforward: what have we learned over the past five months and how might that knowledge put an end to this pandemic?

The Sars-CoV-2 virus almost certainly originated in bats which have evolved fierce immune responses to viruses, researchers have discovered. These defences drive viruses to replicate faster so that they can get past bats’ immune defences. In turn, that transforms the bat into a reservoir of rapidly reproducing and highly transmissible viruses. Then when these bat viruses move into other mammals, creatures that lack a fast-response immune system, the viruses quickly spread into their new hosts. Most evidence suggests that Sars-CoV-2 started infecting humans via an intermediary species, such as pangolins.

“This virus probably jumped from a bat into another animal, and that other animal was probably near a human, maybe in a market,” says virologist Professor Edward Holmes of Sydney University. “And so if that wildlife animal has a virus it’s picked up from a bat and we’re interacting with it, there’s a good chance that the virus will then spread to the person handling the animal. Then that person will go home and spread it to someone else and we have an outbreak.”

As to the transmission of Sars-CoV-2, that occurs when droplets of water containing the virus are expelled by an infected person in a cough or sneeze.

 The way it infects people:

Virus-ridden particles are inhaled by others and come into contact with cells lining the throat and larynx. These cells have large numbers of receptors – known as Ace-2 receptors – on their surfaces. (Cell receptors play a key role in passing chemicals into cells and in triggering signals between cells.) “This virus has a surface protein that is primed to lock on that receptor and slip its RNA into the cell,” says virologist Professor Jonathan Ball of Nottingham University.

Once inside, that RNA inserts itself into the cell’s own replication machinery and makes multiple copies of the virus. These burst out of the cell, and the infection spreads. Antibodies generated by the body’s immune system eventually target the virus and in most cases halt its progress.

“A Covid-19 infection is generally mild, and that really is the secret of the virus’s success,” adds Ball. “Many people don’t even notice they have got an infection and so go around their work, homes and supermarkets infecting others.”

By contrast, Sars – which is also caused by a coronavirus – makes patients much sicker and kills about one in 10 of those infected. In most cases, these patients are hospitalized and that stops them infecting others – by cutting the transmission chain. Milder Covid-19 avoids that issue.

Occasionally, however, the virus can cause severe problems. This happens when it moves down the respiratory tract and infects the lungs, which are even richer in cells with Ace-2 receptors. Many of these cells are destroyed, and lungs become congested with bits of broken cell. In these cases, patients will require treatment in intensive care.

Even worse, in some cases, a person’s immune system goes into overdrive, attracting cells to the lungs in order to attack the virus, resulting in inflammation. This process can run out of control, more immune cells pour in, and the inflammation gets worse. This is known as a cytokine storm (In Greek, “cyto” means cell and “kino” means movement.) In some cases, this can kill the patient.

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Just why cytokine storms occur in some patients but not in the vast majority is unclear. One possibility is that some people have versions of Ace-2 receptors that are slightly more vulnerable to attacks from the coronavirus than are those of most people.

Doctors examining patients recovering from a Covid-19 infection are finding fairly high levels of neutralising antibodies in their blood. These antibodies are made by the immune system, and they coat an invading virus at specific points, blocking its ability to break into cells.

“It is clear that immune responses are being mounted against Covid-19 in infected people,” says virologist Mike Skinner of Imperial College London. “And the antibodies created by that response will provide protection against future infections – but we should note that it is unlikely this protection will be for life.”

Instead, most virologists believe that immunity against Covid-19 will last only a year or two. “That is in line with other coronaviruses that infect humans,” says Skinner. “That means that even if most people do eventually become exposed to the virus, it is still likely to become endemic – which means we would see seasonal peaks of infection of this disease. We will have reached a steady state with regard to Covid-19.”

The virus will be with us for some time, in short. But could it change its virulence? Some researchers have suggested that it could become less deadly. Others have argued that it could mutate to become more lethal. Skinner is doubtful. “We have got to consider this pandemic from the virus’s position,” he says. “It is spreading round the world very nicely. It is doing OK. Change brings it no benefit.”

In the end, it will be the development and roll-out of an effective vaccine that will free us from the threat of Covid-19, Skinner says.

On Friday April 10), the Journal Nature reported that 78 vaccine projects had been launched round the globe – with a further 37 in development. Among the projects that are under way is a vaccine program that is now in phase-one trials at Oxford University, two others at US biotechnology corporations and three more at Chinese scientific groups. Many other vaccine developers say they plan to start human testing this year.

This remarkable response raises hopes that a Covid -19 vaccine could be developed in a fairly short time. However, vaccines require large-scale safety and efficacy studies. Thousands of people would receive either the vaccine itself or a placebo to determine if the former were effective at preventing infection from the virus which they would have encountered naturally. That, inevitably, is a lengthy process.

As a result, some scientists have proposed a way to speed up the process – by deliberately exposing volunteers to the virus to determine a vaccine’s efficacy. “This approach is not without risks but has the potential to expedite candidate vaccine testing by many months,” says Nir Eyal, a professor of bioethics at Rutgers University.

It is expected that the Covid -19 antidote vaccine would soon be available. However, there must be more researches about the efficacy and safety of the vaccine. As thousands people will be given so it should be naturally safe and effective and can combat the spread of infection, it must be ensured.

Source: The Guardian

The BRICS Summit Begins



News Desk, Barta24.com
The BRICS Summit Begins, Photo collected.

The BRICS Summit Begins, Photo collected.

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The leaders of Brazil, Russia, India, China, and South Africa meet virtually today (June 23)  for a summit of BRICS nations. As well as a chance to discuss economic strategies outside a Western-dominated system, the meeting once again shows that, although Russia is isolated from the West, for the rest of the world it is still very much open for business.

According to media repots, Russian President Vladimir Putin joins the gathering today at a time when his country has become China’s largest crude oil supplier—a position usually enjoyed by Saudi Arabia. He will hold talks with a group of leaders who have so far tempered any criticism of the war in Ukraine.

Indeed Xi Jinping, in his address to the BRICS Business forum on Wednesday, appeared to lay the blame on Ukraine for Russia’s invasion, calling it a “wake up call” and a reminder that “attempts to expand military alliances and seek one’s own security at the expense of others will only land oneself in a security dilemma.”

Addressing the same forum, Putin was bullish on the economic opportunities presented by the group, touting negotiations on opening Indian chain stores in Russia, increasing Chinese industrial imports and “reorienting trade flows” to BRICS nations. According to Putin, trade with the group increased by 38 percent in the first quarter of 2022.

He added that the BRICS group could soon go a step further by challenging the U.S. dollar, creating its own international reserve currency based on the “basket of currencies of our countries.”

For India, also a member of the Quad—along with Australia, Japan, and the United States—it faces a challenge to keep up its balancing act between East and West.

“India lives in a rough neighborhood and has been able to stick by its non-aligned policy to ensure its strategic autonomy by essentially engaging with everybody, and they’ve done a pretty good job of that,” Derek Grossman, a senior defense analyst at the RAND Corporation, told Foreign Policy (FP). “But as great power competition continues to heat up, not just between the U.S. and China, but now the U.S. and Russia, it’s going to be increasingly difficult and delicate to maintain that balance.”

Indian officials aren’t naïve about their position, and are reportedly working to block any attempts to insert anti-U.S. messaging into the BRICS joint statement as well as slow any attempts to expand the grouping.

That the BRICS grouping is not known as a particularly effective combination may work in India’s favor. “I think that India can make a gamble, which I think is pretty safe, and it can essentially, pledge full support for everything BRICS is doing to show that it’s a loyal member of the group, while at the same time betting on the strong likelihood that BRICS won’t be able to move the needle forward on a lot of the issues and plans that are discussed,” said Michael Kugelman, an Asia expert at the Wilson Center and author of FP’s South Asia Brief. “That would then spare India from having to make awkward decisions about how far to go and pursue policies within BRICS that could put it at odds with the West.”

India is in high demand in a busy few weeks for Prime Minister Narendra Modi. He travels to Germany over the weekend to attend the G-7 summit and in July he joins another new grouping (and acronym) I2-U2, with the leaders of Israel, the United Arab Emirates, and the United States.

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The Quake was Afghanistan’s Deadliest in Two Decades



News Desk, Barta24.com
The Quake was Afghanistan’s Deadliest in Two Decades

The Quake was Afghanistan’s Deadliest in Two Decades

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Villagers rushed to bury the dead Thursday and dug by hand through the rubble of their homes in search of survivors of a powerful earthquake in eastern Afghanistan that killed at least 1,000 people. The Taliban and the international community that fled their takeover struggled to bring help to the disaster’s victims.

Under a leaden sky in Paktika province, which was the epicenter of Wednesday’s magnitude 6 earthquake, men dug a line of graves in one village, as they tried to lay the dead to rest quickly in line with Muslim tradition. In one courtyard, bodies lay wrapped in plastic to protect them from the rains that are hampering relief efforts for the living.

The quake was Afghanistan’s deadliest in two decades, and officials said the toll could rise. An estimated 1,500 others were reported injured, the state-run Bakhtar News Agency said.

“They don’t have anything to eat, they are wondering what they can have to eat, and it is also raining,” a Bakhtar reporter said in footage from the quake zone. “Their houses are destroyed. Please help them, don’t leave them alone.”

The disaster heaps more misery on a country where millions already faced increasing hunger and poverty and the health system has crumbled since the Taliban retook power nearly 10 months ago amid the U.S. and NATO withdrawal. The takeover led to a cutoff of vital international financing, and most of the world has shunned the Taliban government.

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Afghanistan Quake Kills 1,000 People, Deadliest in Decades



News Desk, Barta24.com
Afghanistan Earthquake, Photo collected

Afghanistan Earthquake, Photo collected

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In this photo released by a state-run news agency Bakhtar, Afghans look at destruction caused by an earthquake in the province of Paktika, eastern Afghanistan, Wednesday (June 22).

The news of Afghanistan quake 'Deadliest in Decades' became the focus of world mrdia. Aaccoding to the report by Bakhtar News Agency via AP, a powerful earthquake struck a rural, mountainous region of eastern Afghanistan early Wednesday, killing 1,000 people and injuring 1,500 more in one of the deadliest quakes in decades. the state-run news agency reported the  officials warned that the already grim toll may still rise.

Information remained scarce on the magnitude 6.1 temblor near the Pakistani border, but quakes of that strength can cause serious damage in an area where homes and other buildings are poorly constructed and landslides are common. Experts put the depth at just 10 kilometers (6 miles) — another factor that could lead to severe destruction.

The disaster posed a major test for the Taliban-led government, which seized power last year as the U.S. planned to pull out from the country and end its longest war, two decades after toppling the same insurgents in the wake of the 9/11 attacks.

Rescuers rushed to the area by helicopter Wednesday, but the response is likely to be complicated since many international aid agencies left Afghanistan after the Taliban takeover. Reaching rural areas even in the best circumstances remains difficult in Afghanistan, a landlocked nation just smaller than Texas with rutted mountain roadways that may now have sustained significant damage.

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Israel’s Government Collapses



News Deak, Barta24.com
Israel’s Government Collapses

Israel’s Government Collapses

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Israel’s governing coalition will vote to dissolve Parliament before the end of the month, the prime minister’s office said Monday (20 July), sending the country into its fifth election in three years.

According to various news agencies, the collapse follows weeks of paralysis caused by the defection of two right-wing lawmakers and frequent rebellions by three others — making Prime Minister Naftali Bennett’s coalition no longer the majority in Parliament. The fallout throws a political lifeline to Benjamin Netanyahu, the former prime minister who left office last June and whose Likud party is currently leading in opinion polls.

The election, which is expected to be held in the fall, comes at a tense time after a rise in Palestinian attacks on Israelis and an escalation in a shadow war between Israel and Iran.

The current coalition agreement requires that Yair Lapid, the foreign minister and a centrist former broadcaster, would take over as interim prime minister in the event that right-wing defections prompt early elections. If that agreement is honored, Lapid will lead the government for at least several months.

Meanwhile, Israel confirmed that it is part of a regional military partnership to combat threats from Iran — the latest example of Israel’s growing engagement with some Arab governments.

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