WHO says reviewing report on concerns over airborne spread of Covid-19

Agencies
July 7, 2020

The World Health Organization (WHO) is reviewing a report that suggested its advice on the novel coronavirus needs updating after some scientists told the New York Times there was evidence the virus could be spread by tiny particles in the air.

The WHO says the Covid-19 disease spreads primarily through small droplets, which are expelled from the nose and mouth when an infected person breaths them out in coughs, sneezes, speech or laughter and quickly sink to the ground.

In an open letter to the Geneva-based agency, 239 scientists in 32 countries outlined the evidence they say shows that smaller exhaled particles can infect people who inhale them, the newspaper said on Saturday.

Because those smaller particles can linger in the air longer, the scientists - who plan to publish their findings in a scientific journal this week - are urging WHO to update its guidance, the Times said.

"We are aware of the article and are reviewing its contents with our technical experts," WHO spokesman Tarik Jasarevic said in an email reply on Monday to a Reuters request for comment.

The extent to which the coronavirus can be spread by the so-called airborne or aerosol route - as opposed to by larger droplets in coughs and sneezes - remains disputed.

Any change in the WHO's assessment of the risk of transmission could affect its current advice on keeping one-metre physical distancing. Governments, which also rely on the agency for guidance policy, may also have to adjust public health measures aimed at curbing the spread of the virus.

"Especially in the last couple of months, we have been stating several times that we consider airborne transmission as possible but certainly not supported by solid or even clear evidence," Benedetta Allegranzi, the WHO's technical lead for infection prevention and control, was quoted as saying in the New York Times.

WHO guidance to health workers, dated June 29, says that SARS-CoV-2, the virus that causes Covid-19, is primarily transmitted between people through respiratory droplets and on surfaces.

But airborne transmission via smaller particles is possible in some circumstances, such as when performing intubation and aerosol-generating procedures, it says.

Medical workers performing such procedures should wear heavy-duty N95 respiratory masks and other protective equipment in an adequately ventilated room, the WHO says.

Officials at South Korea's Centers for Disease Control said on Monday they were continuing to discuss various issues about Covid-19, including the possible airborne transmission. They said more investigations and evidence were needed.

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Agencies
June 12,2020

Global poverty could rise to over one billion people due to the COVID-19 pandemic and more than half of the 395 million additional extreme poor would be located in South Asia, which would be the hardest-hit region in the world, according to a new report.

Researchers from King's College London and Australian National University published the new paper with the United Nations University World Institute for Development Economics Research (UNU-WIDER) said that poverty is likely to increase dramatically in middle-income developing countries and there could be a significant change in the distribution of global poverty.

The location of global poverty could shift back towards developing countries in South Asia and East Asia, the report said.

The paper, 'Precarity and the Pandemic: COVID-19 and Poverty Incidence, Intensity and Severity in Developing Countries,' finds that extreme poverty could rise to over one billion people globally as a result of the crisis.

The cost of the crisis in lost income could reach USD 500 million per day for the world's poorest people, and the intensity and severity of poverty are likely to be exacerbated dramatically.

The report said that based on the USD 1.90 a day poverty line and a 20 per cent contraction, more than half of the 395 million additional extreme poor would be located in South Asia, which would become the hardest hit region in the world mainly driven by the weight of populous India followed by sub-Saharan Africa which would comprise 30 per cent, or 119 million, of the additional poor.

The report added that as the value of the poverty line increases, a larger share of the additional poor will be concentrated in regions where the corresponding poverty line is more relevant given the average income level.

For instance, the regional distribution of the world's poor changes drastically when looking at the USD 5.50 a day poverty line the median poverty line among upper-middle-income countries.

At this level, almost 41 per cent of the additional half a billion poor under a 20 per cent contraction scenario would live in East Asia and the Pacific, chiefly China; a fourth would still reside in South Asia; and a combined 18 per cent would live in the Middle East and North Africa (MENA) and in Latin America and the Caribbean (LAC), whose individual shares are close to that recorded for sub-Saharan Africa.

India plays a significant role in driving the potential increases in global extreme poverty documented previously, comprising almost half the estimated additional poor regardless of the contraction scenario, the report said.

Nonetheless, there are other populous, low and lower-middle- income countries in South Asia, sub-Saharan Africa, and East Asia and the Pacific accounting for a sizeable share of the estimates: Nigeria, Ethiopia, Bangladesh, and Indonesia come next, in that order, concentrating a total of 18 19 per cent of the new poor, whereas the Democratic Republic of Congo, Tanzania, Pakistan, Kenya, Uganda, and the Philippines could jointly add 11 12 per cent.

Taken together, these figures imply that three quarters of the additional extreme poor globally could be living in just ten populous countries.

The report added that this high concentration of the additional extreme poor is staggering , although not necessarily unexpected given the size of each country's population.

On one hand, data shows that three of these ten countries (Ethiopia, India, and Nigeria) were among the top ten by number of extreme poor people in 1990 and remained within the ranks of that group until 2018.

Despite this crude fact, two of these countries have managed to achieve a sustained reduction in their incidence of poverty since the early 1990s, namely Ethiopia and India, reaching their lowest poverty headcount ratio ever recorded at about 22 and 13 per cent, respectively. Nonetheless, the potential contraction in per capita income/consumption imposed by the pandemic's economic effects could erase some of this progress.

The researchers are now calling for urgent global leadership from the G7, G20, and the multilateral system, and propose a three-point plan to address the impact of the COVID-19 on global poverty quickly.

Professor of International Development at King's College London and a Senior Non-Resident Research Fellow at UNU-WIDER Andy Sumner said the COVID-19 crisis could take extreme poverty back over one billion people because millions of people live just above poverty.

Millions of people live in a precarious position one shock away from poverty. And the current crisis could be that shock that pushes them into poverty.

Professor Kunal Sen, Director of UNU-WIDER said the new estimates about the level of poverty in the world and the cost of the COVID-19 pandemic to the world's poor are sobering.

We cannot stand by and see the hard work and effort of so many be eradicated. We will know what the real impact is in time, but the necessary action to ensure we achieve the Sustainable Development Goals by 2030 needs to be planned now, Sen said.

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Agencies
July 2,2020

The American pharmaceutical giant Pfizer Inc. and the European biotechnology company BioNTech SE have conducted an experimental trial of a COVID-19 vaccine candidate and found it to be safe, well-tolerated, and capable of generating antibodies in the patients.

The study, which is yet to be peer-reviewed, describes the preliminary clinical data for the candidate vaccine -- nucleoside-modified messenger RNA (modRNA), BNT162b1.

It said the amount of antibodies produced in participants after they received two shots of the vaccine candidate was greater than that reported in patients receiving convalescent plasma from recovered COVID-19 patients.

"I was glad to see Pfizer put up their phase 1 trial data today. Virus neutralizing antibody titers achieved after two doses are greater than convalescent antibody titers," tweeted Peter Hotez, a vaccine scientist from Baylor College of Medicine in the US, who was unrelated to the study.

Researchers, including those from New York University in the US, who were involved in the study, said the candidate vaccine enables human cells to produce an optimised version of the receptor binding domain (RBD) antigen -- a part of the spike (S) protein of SARS-CoV-2 which it uses to gain entry into human cells.

"Robust immunogenicity was observed after vaccination with BNT162b1," the scientists noted in the study.

They said the program is evaluating at least four experimental vaccines, each of which represents a unique combination of mRNA format and target component of the novel coronavirus, SARS-CoV-2.

Based on the study's findings, they said BNT162b1 could be administered in a quantity that was well tolerated, potentially generating a dose dependent production of immune system molecules in the patients.

The research noted that patients treated with the vaccine candidate produced nearly 1.8 to 2.8 fold greater levels of RBD-binding antibodies that could neutralise SARS-CoV-2.

"We are encouraged by the clinical data of BNT162b1, one of four mRNA constructs we are evaluating clinically, and for which we have positive, preliminary, topline findings," said Kathrin U. Jansen, study co-author and Senior Vice President and Head of Vaccine Research & Development, Pfizer.

"We look forward to publishing our clinical data in a peer-reviewed journal as quickly as possible," Jansen said.

According to Ugur Sahin, CEO and Co-founder of BioNTech, and another co-author of the study, the preliminary data are encouraging as they provide an initial signal that BNT162b1 is able to produce neutralising antibody responses in humans.

He said the immune response observed in the patients treated with the experimental vaccine are at, or above, the levels observed from convalescent sera, adding that it does so at "relatively low dose levels."

"We look forward to providing further data updates on BNT162b1," Sahin said.

According to a statement from Pfizer, the initial part of the study included 45 healthy adults 18 to 55 years of age.

It said the priliminary data for BNT162b1 was evaluated in 24 subjects who received two injections of 10 microgrammes ( g) and 30 g -- 12 subjects who received a single injection of 100 g, and 9 subjects who received two doses of a dummy vaccine.

The study noted that participants received two doses, 21 days apart, of placebo, 10 g or 30 g of BNT162b1, or received a single dose of 100 g of the vaccine candidate.

According to the scientists, the highest neutralising concentrations of antibodies were observed seven days after the second dose of 10 g, or 30 g on day 28 after vaccination.

They said the neutralising concentrations were 1.8- and 2.8-times that observed in a panel of 38 blood samples from people who had contracted the virus.

In all 24 subjects who received two vaccinations at 10 g and 30 g dose levels, elevation of RBD-binding antibody concentrations was observed after the second injection, the study noted.

It said these concentrations are 8- and 46.3-times the concentration seen in a panel of 38 blood samples from those infected with the novel coronavirus.

At the 10 g or 30 g dose levels, the scientists said adverse reactions, including low grade fever, were more common after the second dose than the first dose.

According to Pfizer, local reactions and systemic events after injection with 10 g and 30 g of BNT162b1 were "dose-dependent, generally mild to moderate, and transient."

It said the most commonly reported local reaction was injection site pain, which was mild to moderate, except in one of 12 subjects who received a 100 g dose, which was severe.

The study noted that there was no serious adverse events reported by the patients.

Citing the limitations of the research, the scientists said the immunity generated in the participants in the form of the T cells and B cells of their immune system, and the level of immunity needed to protect one from COVID-19 are unknown.

With these preliminary data, along with additional data being generated, Pfizer noted in the statement that the two companies will determine a dose level, and select among multiple vaccine candidates to seek to progress to a large, global safety and efficacy trial, which may involve up to 30,000 healthy participants if regulatory approval to proceed is received.

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Agencies
May 19,2020

New York, May 19: Cigarette smoke spurs the lungs to make more of the receptor protein which the novel coronavirus uses to enter human cells, according to a study which suggests that quitting smoking might reduce the risk of a severe coronavirus infection.

The findings, published in the journal Developmental Cell, may explain why smokers appear to be particularly vulnerable to severe COVID-19 disease.

"Our results provide a clue as to why smokers who develop COVID-19 tend to have poor clinical outcomes," said study senior author Jason Sheltzer, a cancer geneticist at Cold Spring Harbor Laboratory in the US.

"We found that smoking caused a significant increase in the expression of ACE2, the protein that SARS-CoV-2 uses to enter human cells," Sheltzer said.

According to the scientists, quitting smoking might reduce the risk of a severe coronavirus infection.

They said most individuals infected with the virus suffer only mild illness, if they experience any at all.

However, some require intensive care when the sometimes-fatal virus attacks, the researchers said.

In particular, they said three groups have been significantly more likely than others to develop severe illness -- men, the elderly, and smokers.

Turning to previously published data for possible explanations for these disparities, the scientists assessed if vulnerable groups share some key features related to the human proteins that the coronavirus relies on for infection.

First, they said, they focused on comparing gene activity in the lungs across different ages, between the sexes, and between smokers and nonsmokers.

The scientists said both mice that had been exposed to smoke in a laboratory, and humans who were current smokers had significant upregulation of ACE2.

According to Sheltzer, smokers produced 30-55 per cent more ACE2 than their non-smoking counterparts.

While the researchers found no evidence that age or sex impacts ACE2 levels in the lungs, they said the influence of smoke exposure was surprisingly strong.

However, they said, the change seemed to be temporary.

According to the data, the level of the receptors ACE2 in the lungs of people who had quit smoking was similar to that of non-smokers.

The study noted that the most prolific producers of ACE2 in the airways are mucus-producing cells called goblet cells.

Smoking is known to increase the prevalence of such cells, the scientists said.

"Goblet cells produce mucous to protect the respiratory tract from inhaled irritants. Thus, the increased expression of ACE2 in smokers' lungs could be a byproduct of smoking-induced secretory cell hyperplasia," Sheltzer explained.

However, Sheltzer said other studies on the effects of cigarette smoke have shown mixed results.

"Cigarette smoke contains hundreds of different chemicals. It's possible that certain ingredients like nicotine have a different effect than whole smoke does," he said.

The researchers cautioned that the actual ACE2 protein may be regulated in ways not addressed in the current study.

"One could imagine that having more cells that express ACE2 could make it easier for SARS-CoV-2 to spread in someone's lungs, but there is still a lot more we need to explore," Sheltzer said.

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