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Donald Trump’s ‘Chinese lab’ theory may be weakened by FDA’s
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antikebohongan1
Donald Trump’s ‘Chinese lab’ theory may be weakened by FDA’s
Donald Trump’s ‘Chinese lab’ theory may be weakened by FDA’s bat coronavirus discovery
Gene from Sars-CoV-2 may reduce bat coronavirus’ ability to enter a host cell, study finds
Theory cited by the president and Secretary of State Mike Pompeo suggested Covid-19 was linked to a Wuhan laboratory where a bat virus was studied
A gene that helps the spread of the coronavirus in humans appears to reduce the infectivity of a similar bat virus, according to a new US government study that may cast doubt on a theory that the virus originated in a Chinese laboratory.
The virus raTG13, found in the dung of horseshoe bats in a cave in southwest China, was the closest known cousin to the novel coronavirus, with over 96 per cent similarity in genes. The biggest difference between them was the spikes, or proteins that bind the virus to a host cell.
At the US Food and Drug Administration’s (FDA’s) vector-borne viral diseases laboratory in Maryland, Dr Tony Wang and colleagues conducted an experiment to see what would happen to raTG13 if it were given a spike similar to that of Sars-CoV-2, the coronavirus that causes the disease Covid-19.
US government officials including President Donald Trump and Secretary of State Mike Pompeo have promoted a theory that the Covid-19 outbreak may have started at a laboratory in Wuhan where scientists studied the raTG13 bat virus.
Dr Wang declined to comment on that theory, but said his work was intended to investigate something that could only have happened in a laboratory.
“In nature, there is no evidence that there is such a bat virus that carries the PRRA insert,” he said in a response to the South China Morning Post’s emailed queries on Wednesday.
PRRA is a four-amino-acid insert in the coronavirus’ genome that could cause a small but important change of structure in the spike protein. With the new structure, the spike can split apart more easily, and this may allow the viral envelope to fuse with human cell membrane more efficiently.
Scientists had found similar structures in other highly contagious pathogens such as human immunodeficiency virus (HIV), but not in the coronavirus.
Wang and colleagues created an HIV-based pseudovirus that carried the bat coronavirus’ spike protein with the PRRA insert. A pseudovirus is a modified virus that can infect cells, but safer to handle than a real virus because it replicates only once.
The new spike protein split more easily, as expected, the FDA scientists observed, but there was a negative impact on the pseudovirus’ ability to enter a host cell. The researchers tested it on cells from different potential hosts, including bat and pangolin, and the results were the same.
In human lung cells, for instance, the infectivity dropped by hundreds of times compared with those carrying natural bat virus spikes, according to their non-peer-reviewed paper posted on biorxiv.org on Tuesday. These results were “surprising”, they said.
The origin of Sars-CoV-2 is still a mystery. Although studies by scientists from around the world have produced plenty of evidence against the conspiracy theory that the strain was man-made, the intermediate host of the virus remains an open question.
A wide genetic gap suggested the coronavirus may have separated from its bat relatives, including raTG13, years or even decades ago, but what happened between then and the current global pandemic has been a missing link.
The FDA study found a clue that could help bring the answer a step closer. Of the animals it was tested on, the PRRA insert could boost the bat virus’ ability to infect cells only in mice. This raised a possibility that mice could have been an intermediate host – but many studies, including this one by the FDA, have found that the human coronavirus, despite being able to infect many animals, could not infect mice.
The US government researchers had yet to find an explanation for those seemingly conflicting outcomes, but agreed with the consensus in the global research community that the virus could have existed long before it was detected in China in late December.
“Sars-CoV-2 may well have adapted in humans before the outbreak in Wuhan, China,” they said in the paper
source
Satu lagi kebohongan truml dan pompey dibongkar scr ilmiah oleh ilmuan...tukang bohong memang sangat bahaya.
Gene from Sars-CoV-2 may reduce bat coronavirus’ ability to enter a host cell, study finds
Theory cited by the president and Secretary of State Mike Pompeo suggested Covid-19 was linked to a Wuhan laboratory where a bat virus was studied
A gene that helps the spread of the coronavirus in humans appears to reduce the infectivity of a similar bat virus, according to a new US government study that may cast doubt on a theory that the virus originated in a Chinese laboratory.
The virus raTG13, found in the dung of horseshoe bats in a cave in southwest China, was the closest known cousin to the novel coronavirus, with over 96 per cent similarity in genes. The biggest difference between them was the spikes, or proteins that bind the virus to a host cell.
At the US Food and Drug Administration’s (FDA’s) vector-borne viral diseases laboratory in Maryland, Dr Tony Wang and colleagues conducted an experiment to see what would happen to raTG13 if it were given a spike similar to that of Sars-CoV-2, the coronavirus that causes the disease Covid-19.
US government officials including President Donald Trump and Secretary of State Mike Pompeo have promoted a theory that the Covid-19 outbreak may have started at a laboratory in Wuhan where scientists studied the raTG13 bat virus.
Dr Wang declined to comment on that theory, but said his work was intended to investigate something that could only have happened in a laboratory.
“In nature, there is no evidence that there is such a bat virus that carries the PRRA insert,” he said in a response to the South China Morning Post’s emailed queries on Wednesday.
PRRA is a four-amino-acid insert in the coronavirus’ genome that could cause a small but important change of structure in the spike protein. With the new structure, the spike can split apart more easily, and this may allow the viral envelope to fuse with human cell membrane more efficiently.
Scientists had found similar structures in other highly contagious pathogens such as human immunodeficiency virus (HIV), but not in the coronavirus.
Wang and colleagues created an HIV-based pseudovirus that carried the bat coronavirus’ spike protein with the PRRA insert. A pseudovirus is a modified virus that can infect cells, but safer to handle than a real virus because it replicates only once.
The new spike protein split more easily, as expected, the FDA scientists observed, but there was a negative impact on the pseudovirus’ ability to enter a host cell. The researchers tested it on cells from different potential hosts, including bat and pangolin, and the results were the same.
In human lung cells, for instance, the infectivity dropped by hundreds of times compared with those carrying natural bat virus spikes, according to their non-peer-reviewed paper posted on biorxiv.org on Tuesday. These results were “surprising”, they said.
The origin of Sars-CoV-2 is still a mystery. Although studies by scientists from around the world have produced plenty of evidence against the conspiracy theory that the strain was man-made, the intermediate host of the virus remains an open question.
A wide genetic gap suggested the coronavirus may have separated from its bat relatives, including raTG13, years or even decades ago, but what happened between then and the current global pandemic has been a missing link.
The FDA study found a clue that could help bring the answer a step closer. Of the animals it was tested on, the PRRA insert could boost the bat virus’ ability to infect cells only in mice. This raised a possibility that mice could have been an intermediate host – but many studies, including this one by the FDA, have found that the human coronavirus, despite being able to infect many animals, could not infect mice.
The US government researchers had yet to find an explanation for those seemingly conflicting outcomes, but agreed with the consensus in the global research community that the virus could have existed long before it was detected in China in late December.
“Sars-CoV-2 may well have adapted in humans before the outbreak in Wuhan, China,” they said in the paper
source
Satu lagi kebohongan truml dan pompey dibongkar scr ilmiah oleh ilmuan...tukang bohong memang sangat bahaya.
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Lancet COVID-19 and China: lessons and the way forward - The Lancet
Lancet COVID-19 and China: lessons and the way forward - The Lancet
China has largely controlled COVID-19. A country of 1·4 billion people and a size similar to Europe or the USA now reports only clusters of cases rather than widespread community transmission.
China has been widely criticised for its role and responsibilities during the pandemic because of censorship, transparency, and human rights concerns. But the rest of the world can still learn from China’s successes in bringing its outbreak under control.China’s response shows the importance of domestic research and public health capacity.
Huge investments have left China much better prepared for COVID-19 than for severe acute respiratory syndrome (SARS). When SARS broke out in 2002, China was unprepared initially, especially as the pathogen was unknown. When COVID-19 emerged in December, 2019, Chinese scientists were quickly able to identify the virus and shared genomic sequencing data internationally on Jan 11, 2020.
By the end of January, doctors from mainland China and Hong Kong had characterised the clinical features of patients with COVID-19, person-to-person transmission,
genomic characteristics, and epidemiology, warning the world about the threat of COVID-19 with research papers published in The Lancet. China has also been at the forefront of vaccine research, with promising results
of early trials of a recombinant adenovirus type-5-vectored COVID-19 vaccine developed in China published in The Lancet in May and July.
Such research was done incredibly fast and rigorously through close cooperation within China at a time of national emergency. For other countries, particularly low-income and middle-income countries, China’s experience shows the importance of investing in national health and research systems to enhance laboratory capacity as well as workforce.
They are fundamental to a quick and effective national response to health emergencies and to global health security.A second lesson is that a robust foundation of research cannot guarantee effective control without strong top-level political commitment to use science to tackle the
outbreak decisively.
Governments and their leaders must respect science, understand its value, and act on it in a way that is best for society. China’s National Health Commission sent three groups of national Infectious disease experts to Wuhan at the beginning of the outbreak to investigate the risks and transmission of COVID-19, and their recommendations informed. the decision to lockdown Wuhan on Jan 23. When Chen Wang, president of the Chinese Academy of Medical Sciences, and colleagues saw the need for Fangcang shelter hospitals, the government was quick to respond.
Third, achieving rapid and effective implementation
of control measures for COVID-19 requires broad
community engagement. Community solidarity has
been unprecedented during the COVID-19 outbreak in
China. Control measures that could sacrifice individual
freedom, like mandatory mask-wearing in public areas,
were accepted readily by the public. Millions of China’s
community workers have “built the first line of defense
against COVID-19”, according to Xinhua News Agency,
in their work to provide essential health checks and
support for people with fever, severe diseases, pregnant
women, and those quarantined at home. There are
tensions between freedom and security that each country
has to reckon with, and some of China’s approaches
to surveillance, for example, would not be acceptable
elsewhere. But China’s experiences show the importance
of community solidarity and what it can achieve.
So, there are lessons for health to learn from China. But how will Chinese and global health communities work together in the future? China’s Foreign Minister Wang Yi has said that globalisation needs to be more inclusive and beneficial to all, that multilateralism must Be safeguarded and promoted even more firmly, and that global governance needs to be reformed and improved where it is most lacking. The health community is waiting to see if China will become a multilateral leader in global health, what role it wants in international global health security, and whether it will aspire to fill the vacuum in global health left by the USA.
China is facing legitimate questions in many areas of its domestic and foreign policy, but when it comes to COVID-19, scapegoating China for the pandemic is not a constructive response. “Now is the time for global leaders to decide: will we succumb to chaos, division and inequality? Or will we right the wrongs of the past and move forward together, for the good of all?”, as UN Secretary-General António Guterres asked in his 2020
Nelson Mandela Annual Lecture. Tackling a global health
emergency like a pandemic requires open collaboration.
The lack of global solidarity to address COVID-19 amid
geopolitical instability is a threat to us all.
The Lancet
https://www.thelancet.com/pdfs/journ...NhiVKq6UgcWIpM
China has largely controlled COVID-19. A country of 1·4 billion people and a size similar to Europe or the USA now reports only clusters of cases rather than widespread community transmission.
China has been widely criticised for its role and responsibilities during the pandemic because of censorship, transparency, and human rights concerns. But the rest of the world can still learn from China’s successes in bringing its outbreak under control.China’s response shows the importance of domestic research and public health capacity.
Huge investments have left China much better prepared for COVID-19 than for severe acute respiratory syndrome (SARS). When SARS broke out in 2002, China was unprepared initially, especially as the pathogen was unknown. When COVID-19 emerged in December, 2019, Chinese scientists were quickly able to identify the virus and shared genomic sequencing data internationally on Jan 11, 2020.
By the end of January, doctors from mainland China and Hong Kong had characterised the clinical features of patients with COVID-19, person-to-person transmission,
genomic characteristics, and epidemiology, warning the world about the threat of COVID-19 with research papers published in The Lancet. China has also been at the forefront of vaccine research, with promising results
of early trials of a recombinant adenovirus type-5-vectored COVID-19 vaccine developed in China published in The Lancet in May and July.
Such research was done incredibly fast and rigorously through close cooperation within China at a time of national emergency. For other countries, particularly low-income and middle-income countries, China’s experience shows the importance of investing in national health and research systems to enhance laboratory capacity as well as workforce.
They are fundamental to a quick and effective national response to health emergencies and to global health security.A second lesson is that a robust foundation of research cannot guarantee effective control without strong top-level political commitment to use science to tackle the
outbreak decisively.
Governments and their leaders must respect science, understand its value, and act on it in a way that is best for society. China’s National Health Commission sent three groups of national Infectious disease experts to Wuhan at the beginning of the outbreak to investigate the risks and transmission of COVID-19, and their recommendations informed. the decision to lockdown Wuhan on Jan 23. When Chen Wang, president of the Chinese Academy of Medical Sciences, and colleagues saw the need for Fangcang shelter hospitals, the government was quick to respond.
Third, achieving rapid and effective implementation
of control measures for COVID-19 requires broad
community engagement. Community solidarity has
been unprecedented during the COVID-19 outbreak in
China. Control measures that could sacrifice individual
freedom, like mandatory mask-wearing in public areas,
were accepted readily by the public. Millions of China’s
community workers have “built the first line of defense
against COVID-19”, according to Xinhua News Agency,
in their work to provide essential health checks and
support for people with fever, severe diseases, pregnant
women, and those quarantined at home. There are
tensions between freedom and security that each country
has to reckon with, and some of China’s approaches
to surveillance, for example, would not be acceptable
elsewhere. But China’s experiences show the importance
of community solidarity and what it can achieve.
So, there are lessons for health to learn from China. But how will Chinese and global health communities work together in the future? China’s Foreign Minister Wang Yi has said that globalisation needs to be more inclusive and beneficial to all, that multilateralism must Be safeguarded and promoted even more firmly, and that global governance needs to be reformed and improved where it is most lacking. The health community is waiting to see if China will become a multilateral leader in global health, what role it wants in international global health security, and whether it will aspire to fill the vacuum in global health left by the USA.
China is facing legitimate questions in many areas of its domestic and foreign policy, but when it comes to COVID-19, scapegoating China for the pandemic is not a constructive response. “Now is the time for global leaders to decide: will we succumb to chaos, division and inequality? Or will we right the wrongs of the past and move forward together, for the good of all?”, as UN Secretary-General António Guterres asked in his 2020
Nelson Mandela Annual Lecture. Tackling a global health
emergency like a pandemic requires open collaboration.
The lack of global solidarity to address COVID-19 amid
geopolitical instability is a threat to us all.
The Lancet
https://www.thelancet.com/pdfs/journ...NhiVKq6UgcWIpM
Diubah oleh antikebohongan1 26-07-2020 08:52
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