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Coronavirus: Immunity passports 'could increase virus spread' – BBC News

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Governments should not issue so-called “immunity passports” or “risk-free certificates” as a way of easing lockdowns, the World Health Organization (WHO) says.

It said there was “no evidence” that people who had developed antibodies after recovering from the virus were protected against a second infection.

Such a move could actually increase virus transmission, it warned.

People who assumed they were immune might stop taking precautions, it said.

Some governments have considered permitting people who have recovered to travel or return to work.

Restrictions imposed on movement to stop the virus spreading have crippled economies around the world.

More than 2.8m cases of the virus have been confirmed worldwide and nearly 200,000 people have died.

What did the WHO say?

“There is currently no evidence that people who have recovered from Covid-19 and have antibodies are protected from a second infection,” the WHO said in a briefing note.

Most studies carried out so far showed that people who had recovered from infection had antibodies in their blood – but some of these people had very low levels of antibodies.

This suggested that another part of the body’s immune response – T-cells, which eliminate infected cells – may also be “critical” for recovery.

As of Friday no study had evaluated whether the presence of antibodies to the virus conferred immunity to subsequent infection by the virus in humans, the WHO said.

“At this point in the pandemic, there is not enough evidence about the effectiveness of antibody-mediated immunity to guarantee the accuracy of an ‘immunity passport’ or ‘risk-free certificate’,” it said.

The organisation also said laboratory tests to detect antibodies needed further validation to determine their accuracy and also needed to distinguish between previous infection by the SARS-CoV-2 virus – which has caused the pandemic – and the six other known coronaviruses in circulation.

Passports too risky – for now

Analysis by Rachel Schraer, BBC health reporter

The WHO’s guidance is based on evidence from researchers all around the world. But it could well change as we rapidly learn more about this virus.

There isn’t currently any evidence to suggest having had the virus once protects you from getting it again. So the idea of an “immunity passport”, allowing people who test positive for antibodies to have fewer restrictions, would be a very risky one.

Many countries including Germany, Italy and the UK are beginning to test samples of their populations for antibodies. In the UK, 25,000 people will be tested every month for the next year – both for antibodies, and to check if they currently have the virus.

This could provide more information about whether (and for how long) the disease confers immunity to those who have recovered. And that would give us a clearer idea about whether testing individuals and giving them some kind of immunity status might be an option in the future.

Where are ‘immunity passports’ being considered?

Last week Chile said it would begin issuing “health passports” to people deemed to have recovered from the illness.

Once screened for the presence of antibodies to make them immune to the virus, they could rejoin the workforce, officials said.

In Sweden, which has chosen to keep large parts of society open, some scientists believe people may end up with much higher immunity levels compared with those living under stricter regulations.

However Anders Wallensten from the Swedish Public Health Agency told the BBC that not enough was yet known about immunity.

“We will know more as more people are tested for antibodies, but also the more time goes on, and if more accounts of re-infection etcetera are reported,” he said.

In Belgium, which has one of the highest death rates per capita but is planning to gradually relax lockdown restrictions from 11 May, a government adviser told the BBC he strongly opposed the idea of immunity passports.

“I abhor the fact that we would give people passports, a green one or a red one, depending on their serology status,” said virologist Professor Marc Van Ranst, a member of the Belgian government’s Risk Assessment Group and Scientific Committee on the Coronavirus.

“That will lead to forgeries, that will lead to people wilfully infecting themselves to the virus. This is just not a good idea. It is an extremely bad idea.”

Earlier this week Professor Mala Maini from University College London said reliable antibody tests were urgently needed to determine how long antibodies persisted and whether they conferred protection.

“We’re not yet sure if these antibodies indicate protective immunity against SARS-CoV-2 but preliminary data suggest they may be a reasonable proxy for this – so they are being considered to inform release from lockdown etc,” she said.

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WHO stops hydroxychloroquine trials over safety concerns – Bangkok Post

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The coronavirus pandemic has hammered Latin America, with Brazil the latest epicentre of the disease.

GENEVA: The WHO suspended trials of the drug that Donald Trump has promoted as a coronavirus defence, fuelling concerns about the US president’s handling of the pandemic that has killed nearly 100,000 Americans.

Trump has led the push for hydroxychloroquine as a potential shield or treatment for the virus, which has infected nearly 5.5 million people and killed 345,000 around the world, saying he took a course of the drug as a preventative measure.

Brazilian President Jair Bolsonaro has also heavily promoted hydroxychloroquine while the virus has exploded across nation, which this week became the second most infected in the world after the United States.

But the World Health Organization said Monday it was halting testing of the drug for Covid-19 after studies questioned its safety, including one published Friday that found it actually increased the risk of death.

The WHO “has implemented a temporary pause… while the safety data is reviewed”, its chief Tedros Adhanom Ghebreyesus said, referring to the hydroxychloroquine arm of a global trial of various possible treatments.

Trump announced last week he was taking the drug, explaining he had decided to take after receiving letters from a doctor and other people advocating it.

“I think it’s good. I’ve heard a lot of good stories,” Trump told reporters then, as he declared it safe.

Trump dismissed the opinions then of his own government’s experts who had warned of the serious risks associated with hydroxychloroquine, with the Food and Drug Administration highlighting reported poisonings and heart problems.

Trump has been heavily criticised for his handling of the virus, after initially downplaying the threat and then repeatedly rejecting scientific analysis.

The United States has by far the world’s highest coronavirus death toll, reaching 98,218 on Monday, with more than 1.6 million confirmed infections.

Despite the WHO suspension, Brazil’s health ministry said Monday it would keep recommending hydroxychloroquine for Covid-19.

“We’re remaining calm and there will be no change,” health ministry official Mayra Pinheiro told a news conference.

Bolsonaro is a staunch opponent of lockdown measures and like Trump has played down the threat of the virus, even as Latin America has emerged as the new global virus hotspot.

Brazil has reported nearly 375,000 cases, widely considered to be far fewer than the real number because of a lack of testing, and more than 23,000 deaths.

Chile also is in the grip of a virus surge, with a record of nearly 5,000 infections in 24 hours on Monday.

– ‘Thrilled to break the isolation’ –

While South America and parts of Africa and Asia are only just beginning to feel the full force of the pandemic, many European nations are easing lockdowns as their outbreaks are brought under control.

In hard-hit Spain, Madrid and Barcelona on Monday emerged from one of the world’s strictest lockdowns, with parks and cafe terraces open for the first time in more than two months.

Elsewhere, gyms and swimming pools reopened in Germany, Iceland, Italy and Spain.

And slowing infection rates in Greece allowed restaurants to resume business a week ahead of schedule — but only for outdoor service.

“I’m thrilled to break the isolation of recent months and reconnect with friends,” said pensioner Giorgos Karavatsanis.

“The cafe in Greece has a social dimension, it’s where the heart of the district beats.”

Despite the encouraging numbers, experts have warned that the virus could hit back with a devastating second wave if governments and citizens are careless, especially in the absence of a vaccine.

The latest reminder of the threat came from Sweden, where the Covid-19 death toll crossed 4,000 — a much higher figure than its neighbours.

The Scandinavian nation has gained international attention — and criticism — for not enforcing stay-at-home measures like other European countries.

– ‘What will happen if I die’ –

The extended lockdowns, however, have started to bite globally, with businesses and citizens wearying of confinement and suffering immense economic pain.

Unprecedented emergency stimulus measures have been introduced, as governments try to provide relief to their economies, with the airline and hospitality sectors hit particularly hard because of travel bans.

Lufthansa became the latest major global company to be rescued, as the German government agreed a 9 billion euros ($9.8 billion) bailout for one of the world’s biggest airlines.

But analysts have warned that the pandemic’s economic toll will be even more painful for countries far poorer than Western nations.

In the Maldives, a dream destination for well-heeled honeymooners, tens of thousands of impoverished foreign labourers have been left stranded, jobless and ostracised as the tiny nation shut all resorts to stop the virus.

“We need money to survive. We need our work,” said Zakir Hossain, who managed to send about 80 percent of his $180 a month wage to his wife and four children in Bangladesh before the outbreak.

“I heard that if a Bangladeshi worker dies here, they don’t send his body back and he is buried here,” he said. “I am worried what will happen if I die.”

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WHO stops hydroxychloroquine trial in COVID-19 patients due to safety concerns – CANOE

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GENEVA — The World Health Organization has suspended testing the malaria drug hydroxychloroquine in COVID-19 patients due to safety concerns, WHO Director General Tedros Adhanom Ghebreyesus said on Monday.

Hydroxycholoroquine has been touted by Donald Trump and others as a possible treatment for the disease caused by the novel coronavirus. The U.S. President has said he was taking the drug to help prevent infection.

“The executive group has implemented a temporary pause of the hydroxychloroquine arm within the Solidarity trial while the safety data is reviewed by the data safety monitoring board,” Tedros told an online briefing.

He said the other arms of the trial – a major international initiative to hold clinical tests of potential treatments for the virus – were continuing.

The WHO has previously recommended against using hydroxychloroquine to treat or prevent coronavirus infections, except as part of clinical trials.

Dr. Mike Ryan, head of the WHO emergencies program, said the decision to suspend trials of hydroxychloroquine had been taken out of “an abundance of caution.”

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Promising results from VIDO-InterVac's COVID-19 vaccine pre-clinical trials – paNOW

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Several weeks ago, two doses of vaccine were given to the animals. Time was needed to then assess their immune response against a control group.

So how effective exactly is the vaccine so far?

“In the vaccinated animals – the ones that responded to the vaccine – we saw almost undetectable amounts of virus afterwards,” says Gerdts. “So, that’s very good news, and in comparison to the control group per swap… this is a range in a 50,000 fold reduction of it.”

All of the ferrets that were infected received what Gerdts says is a ‘high’ dose, or one million particles of the disease. Depending on exposure levels, it’s not even in the range of what a human would be exposed to, even with a high ‘virus shedder.’

Data on the lungs of the ferrets is still being analysed, but initial results indicate a very high immune response as well as high levels of neutralizing antibodies. It does not appear as though any other organs were affected by the virus either.

At this point, Gerdts says they are now in the midst of producing clinical grade vaccine doses that can be used in humans. He calls it the most time consuming part of the vaccine development.

In the meantime, they’re also conducting safety studies – which are required by regulators to essentially move on to human trials.

“In these safety studies, we’ll address whether there’s any unwanted effects or any adverse events to the vaccine. And also with this particular disease there is concern about what is called ‘disease enhancement’ where the vaccine would actually enhance the disease. So, there’s particular studies that will help us to rule out that our vaccine will do that.”

Gerdts admits that there is some concern that certain vaccines being developed currently may actually make the disease worse. It happened when a vaccine was developed for the virus that causes Dengue Fever several years ago.

“The technology that we have chosen is one that has a very well proven track record in humans and animals… and the advantage of that, is that it’s easily ‘scalable.’ So, at the end, we can produce millions of doses in a single run in a manufacturing facility. So while maybe it’s a bit slower at the moment, the advantage of our vaccine will be that it’s easier to scale and more cost effective.”

If all goes well, human trials are scheduled to begin in the fall.

“This is a vaccine made by Canadians for Canadians. So, we will make sure that our vaccine is available to Canadians at the highest priority.”

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