Category: COVID

Categories : COVIDTags :

Little Traitors: Infection-Enhancing Antibodies in Severe COVID

On By ModernMedia

Osaka University researchers have discovered that infection with SARS-CoV-2 results in not only the production of neutralising antibodies that prevent infection, but also of infection-enhancing antibodies.

Both neutralising antibodies that protect against infection as well as infection-enhancing antibodies that increase infectivity are produced after infection with SARS-CoV-2 by analysing antibodies from COVID patients.

Virus-specific antibodies generally are considered antiviral, playing an important role in the control of virus infections. In some cases however, the presence of specific antibodies can benefit the virus. This activity is known as antibody-dependent enhancement of virus infection, a phenomenon in which virus-specific antibodies enhance the entry of virus, and in some cases the replication of virus, into monocytes/macrophages and granulocytic cells through interaction with Fc and/or complement receptors. 

In COVID infections, antibodies that target the receptor binding site (RBD) of the SARS-CoV-2 spike protein play an important function as neutralising antibodies that suppress SARS-CoV-2 infection by preventing it from binding to the human receptor, ACE2. However, the function of antibodies against other sites of the spike protein was not known.

“We found that when infection-enhancing antibodies bind to a specific site on the spike protein of SARS-CoV-2, the antibodies directly cause a conformational change in the spike protein, resulting in the increased infectivity of SARS-CoV-2. Neutralising antibodies recognise the RBD, whereas infection-enhancing antibodies recognise specific sites of the N-terminal domain (NTD),” explained lead researcher Professor Hisashi Arase. “Furthermore, the production of infection-enhancing antibodies attenuated the ability of neutralising antibodies to prevent infection.”

The study found that patients with severe COVID produced more infection-enhancing antibodies. Non-infected individuals were also found to possibly have small amounts of infection-enhancing antibodies.

Though infection-enhancing antibodies may be involved in the development of severe disease, further research is necessary to determine whether they are in fact involved in the worsening of infection in the body.

A possible benefit would be that by analysing the antibody titer of infection-enhancing antibodies, it would be possible to see who would be prone to severe COVID. The findings are also important for the development of vaccines that do not induce the production of infection-enhancing antibodies.

“It is important to analyse not only neutralising antibodies but also infection-enhancing antibodies. In the future, it may be necessary to develop vaccines that do not induce the production of infection-enhancing antibodies, because infection-enhancing antibodies may be more effective against mutant strains in which neutralising antibodies are not sufficiently effective,” says Professor Hisashi Arase.

Source: Osaka University

Journal information: Yafei Liu et al, An infectivity-enhancing site on the SARS-CoV-2 spike protein targeted by antibodies, Cell (2021). DOI: 10.1016/j.cell.2021.05.032

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Risk of COVID Infection Tripled in Healthcare Workers

On By ModernMedia
Photo by Alex Mecl on Unsplash

A study of healthcare workers has shown their likelihood of being infected with COVID during the pandemic was three times higher compared to the general population, with about one in five of those infected workers being asymptomatic and unaware they had COVID.

The study also shows that it was not only frontline staff who faced the higher risk, suggesting that there was transmission between staff and within the wider community. The results are published in ERJ Open Research.

However, health care workers who had been infected were very unlikely to contract COVID a second time in the following six months.

The research was led by Professor James Chalmers, a consultant respiratory physician from the University of Dundee.

“We have always believed that front line health workers face a high risk of contracting COVID and that’s why we’ve tried to ensure they have the PPE needed to protect themselves,” said Prof Chalmers. “But many questions remain about the level of this risk and what other measures we can take to protect staff and reduce transmission of the disease.”

The study recruited 2063 staff working in a wide variety of healthcare roles in the East of Scotland. Between May and September 2020, the participants had blood tests for COVID antibodies, a very accurate indication of prior COVID infection. The researchers also recorded whether any participants developed an infection in subsequent months.

The health care workers results were compared with a randomly selected control group of blood samples taken by local GPs during the same time period.

These blood tests showed that 300 (14.5%) of the healthcare workers had been infected, a rate more than triple the proportion of people infected in the local population. The highest rates of infections among the workers were found in dentistry (26%), health care assistants (23.3%) and hospital porters (22.2%). The rate among admin staff was the same as that of doctors (21.1%).

Rates among people working in areas of the hospital where COVID patients were being treated were somewhat higher than those working in non-COVID areas (17.4% vs 13.5%). However, the majority of infections were in staff who were not working directly with COVID patients, suggesting there was transmission between staff or infections acquired in the community.

Out of the 300 healthcare workers testing positive, 56 (18.7%) did not think that they had ever caught COVID and were totally asymptomatic. This is an important finding, according to the researchers, since people without symptoms are likely to go to work, potentially infecting others.

In the months following their blood tests, 39 workers developed a symptomatic COVID infection, but only one of these was a worker who had previously tested positive. This equates to an 85% risk reduction, similar to the level of protection provided by COVID vaccines.

Prof Chalmers said: “A lot of attention during the pandemic has been around PPE for doctors and nurses but we found that dentists, healthcare assistants and porters were the staff most likely to test positive.

“We continued to monitor staff for up to seven months and found that having a positive antibody test gave 85% protection against a future infection. This is really good news for people who have already had COVID-19, as it means the chances of a second infection are very low.”

The team hopes to continue the research to see how long immunity persists and how vaccination affects infections among healthcare workers.

Professor Anita Simonds, President of the European Respiratory Society and Consultant in Respiratory and Sleep Medicine at Royal Brompton Hospital, UK, was not involved in the research, offered comments.

She said: “This research shows the high levels of COVID infection among all healthcare workers, with the highest evidence of infection in dentists, healthcare assistants and porters. Staff working in critical care, who are likely to have been protected by using personal protective equipment at all times, were not disproportionately affected.

“It should be noted that among administrative staff, 21.1% were found to have been infected with COVID, indicating that all those working directly with patients, and those working in other hospital roles are at risk, and vaccination and risk assessment for appropriate levels of PPE in all these frontline groups are crucial.”

Source: European Respiratory Society

Categories : COVIDTags : 1 Comment

Case Positivity Rate in SA Breaches The Crucial 10% Mark

On By ModernMedia

Although new COVID cases have not yet shown an upward surge, the fact that the test positivity rate had climbed past 10% is cause for concern.

According to health minister Dr Zweli Mkhize, the 2383 new infections recorded in the past 24 hours came from 23 352 tests at a positivity rate of 10.2%. Yesterday the positivity rate stood at 9.86%, and in the days beforehand had been gradually creeping upward.

The government has previously expressed concern when the positivity rate (the percentage of COVID tests that return positive) reaches the 10% and 12% marks. In late November, ahead of the second wave, the case positivity rate was 14.5%. Some provinces of South Africa are reporting rates well in excess of this, particularly the Northern Cape which last week had a reported positivity rate of 24.1%.

Dr Mkhize also reported that there were 72 Covid-19 related deaths in the past 24 hours. The health minister also reported that across SA there were now 171 860 people who had received their first shot of the two-dose Pfizer vaccine.

With these latest figures, there are now 1 637 848 cumulative cases and 55 874 cumulative fatalities since the outbreak of the coronavirus in SA in March last year. However, the true toll may be much higher, as South Africa’s ‘excess deaths’, those which are above the average rate of deaths from all causes, were up to 2.67 times higher than the official toll. A report from a team at the SA Medical Research Council and University of Cape Town believed that around 85% of those excess deaths were due to COVID.

Source: Times Live

Categories : COVID General InterestTags :

Indian Doctors Hit Back at Guru’s Inflammatory Remarks

On By ModernMedia
Image source: Naveed Ahmed on Unsplash

Doctors in India have hit out against yoga guru Baba Ramdev over his controversial statements against modern medicine and mocking of COVID patients.

Recently, the controversial guru said that tens of thousands died of COVID after taking modern medicines, and also mocked patients for trying to get oxygen cylinders. 

The guru subsequently withdrew his statement after being criticised by the country’s health minister. But on Monday he again took a swipe at modern medicine for not having a cure for some diseases.

Despite India’s modern allopathic healthcare system, alternative therapies like ayurveda and homoeopathy are hugely popular in India. This has helped many gurus to launch successful businesses with sales of herbal medicines and products. India also has a Ministry of Ayurveda, Yoga & Naturopathy, Unani, Siddha and Homoeopathy (Ayush) that promotes traditional medicine systems.

The Indian Medical Association (IMA), which represents allopathy doctors in India, has criticised the guru for his “insensitive” remarks in the middle of the pandemic. Such statements from a guru with millions of followers were “irresponsible and demoralising”, said doctors spoken to by the BBC.
The country has been grappling with a surge of infections caused by a ‘double mutant’ SARS-CoV-2 variant as well as prematurely relaxed social distancing rules.

The controversy
A video of Baba Ramdev mocking patients for trying to find oxygen went viral earlier this month, making references to oxygen shortages in several cities in April and May.

“God has given us free oxygen, why don’t we breathe that? How can there be a shortage when God has filled the atmosphere with oxygen? Fools are looking for oxygen cylinders. Just breathe the free oxygen. Why are you complaining about shortage of oxygen and beds and crematoriums?” he said.

The statement drew sharp criticism from doctors and families of COVID patients who demanded an apology.

Just two weeks later, another video surfaced in which he criticises doctors, blaming COVID deaths on them. Many doctors expressed their anger over Twitter, some went so far as to demand his arrest. In the face of mounting pressures, India’s Health Minister Dr Harsh Vardhan issued a statement asking the guru to withdraw his remarks.

“Allopathy and the doctors attached to it have given new lives to millions of people. It’s very unfortunate for you to say that people died from consuming allopathic medicines.

“We should not forget that this battle can only be won through united efforts. In this war, our doctors, nurses and other health workers are risking their lives to save people’s lives. Their dedication towards serving mankind in this crisis is unparalleled and exemplary,” Dr Vardhan said.

Baba Ramdev withdrew his controversial statement in a Sunday tweet — only to issue a letter the next day asking the IMA why modern medicine had no cure for 25 diseases, including diabetes and hypertension.

This has again infuriated doctors. Prominent pulmonologist Dr A Fathahudeen, who has treated thousands of COVID patients, told the BBC that such statements cause lasting damage.

“For more than a year, healthcare workers like me have been in a war-like situation. We have saved tens of thousand of lives. It’s really unfortunate, insulting and hurtful to read such statements,” he said.

Dr Fathahudeen added that modern medicine had evolved over the years with constant research and studies. “We follow evidence-based practice. At any given time, thousands of researchers are working to come up with cures. Look at the progress we have made in cancer treatment. We have to constantly evolve and learn. It’s hard to trust any branch of medicine that offers absolute cure for every disease.”

Dr Fathahudeen also said that such statements manifest doubts in the minds of people when trust in medicines and vaccines is most needed in the middle of a raging pandemic.

Baba Ramdev’s rise to fame
Televised yoga classes were Baba Ramdev’s ticket to fame; he had a following of millions and he received worldwide praise for promoting yoga and healthy living.

He successfully leveraged his fame to create a business empire. In 2006, he helped launch a company called Patanjali Ayurveda to sell herbal medicines and a few years later, the business expanded to sell almost any product. Since last year, the company has been selling a product called Coronil that it has made a number of false claims over, including that it was a WHO-approved COVID treatment.

Source: BBC News

Categories : COVIDTags :

‘Lab Leak’ Theory Gains Ground with Report of Sick Wuhan Lab Staff in 2019

On By ModernMedia
Image source: CDC/Unsplash

As reported by the Wall Street Journal, US intelligence learned three doctors at Wuhan Institute of Virology became sick with COVID-like symptoms in November 2019 and sought out hospital care. This, along with an open letter in the journal Science has prompted new calls to find out whether COVID started at that facility. 

A State Department report was issued during the last days of former President Donald Trump’s administration but officials familiar with the report did not agree on the strength of the evidence found, the Journal reported. However this new report adds more detail, and comes on the eve of a World Health Organization meeting, which will no doubt include COVID.

In March, virologist Marion Koopmans told NBC News that the illness of lab workers could be due to normal seasonal illnesses.

Earlier this year, a team from the WHO spent a month in Wuhan investigating the origin of the virus, and produced a report concluding that the virus most likely jumped from bats to people, rating a lab leak as “extremely unlikely”.

The WHO however also said it also did not have access to all the necessary information – a situation has prompted some experts to be wary of the findings and demand more investigations into the virus’s origin, including the possibility that it in fact was leaked from a lab.

November 2019 is also in line with when experts believe COVID began circulating.

For its own part, China has consistently denied that the coronavirus escaped from a lab. However, the lab has not made available its raw data or records on its work with coronaviruses in bats.

A spokeswoman for the National Security Council told the Wall Street Journal that the Biden administration has questions about the virus’, but plausible theories should be investigated by WHO.

“We’re not going to make pronouncements that prejudge an ongoing WHO study into the source of SARS-CoV-2,” the spokeswoman said. “As a matter of policy we never comment on intelligence issues.”

Source: Business Insider

Categories : COVIDTags :

Lockdowns Loom as COVID Spreads Again in SA Provinces

On By ModernMedia
Image source: CDC/Unsplash

The Western Cape provincial government has said it is actively preparing for a resurgence of COVID cases while three other provinces have now declared they are in a third wave.

The province’s premier Alan Winde said in a statement on Sunday that based on current trajectories, the province is likely to officially enter its third wave two to three weeks from now.

Gauteng premier David Makhura confirmed that his province officially entered into a third wave more than a week ago. This was followed by similar declarations in the Free State and the Eastern Cape.

“The Western Cape is currently facing a resurgence as it has seen increases in its case numbers every day, over the past 12 days. While this is not yet a third wave, it is the first sign that we are moving towards one,” Winde said.

“Our guiding principle remains that no person will be denied access to life-saving medical treatment. We must make sure we have enough beds, staff and oxygen to respond effectively in the month ahead.”

He added that in the meantime South Africans should continue to follow the level 1 lockdown restrictions, adhering to social distancing and avoid social gatherings to help flatten this curve. But health experts have warned that the rise in cases could require further lockdown restrictions.

Head of the Western Cape Health Department Dr Keith Cloete told EWN that it is a national competency to put lockdown restrictions in place, but they are highly likely to appear given that the number of cases is on the increase countrywide.

Health minister Dr Zweli Mkhize has likewise warned of likely additional restrictions in South Africa due to rising COVID numbers.

He said that the government has discussed the rising numbers. “At some point we are going to have to start looking at additional restrictions,” he said.

“We are going to be recommending that there should be more focus on the size of gatherings, and look at the focus on some of the measures that were actually released when we thought the situation was much more improved.”

He highlighted the importance of trying to maintain a balance to ensure that people continue to be able to work. “We do need to send a strong message still, that people can’t be complacent.”

As of 23 May, there were 2894 new cases in South Africa and the COVID test positive rate stood at 9.86%. Data collected up to 15 May showed the highest positive rate was in the Northern Cape (24.1%), Free State (17.5%) and North West (15.1%) provinces. The percentage testing positive was <10% in all other provinces. (Source: NICD PDF, note this is a 10 MB size)

Source: BusinessTech

Categories : COVID VaccinesTags :

South Africa to Sign On to Digital ‘Vaccine Passport’

On By ModernMedia
Photo by Blake Guidry on Unsplash

Transport minister Fikile Mbalula said that South Africa will seek to join a digital ‘vaccine passport’ scheme being tested by a number of airlines.

Presenting his departmental budget speech on Friday, Mbalula said that South Africa must ensure that it joins the growing number of countries that accepts the International Air Transport Association’s (IATA) mobile travel pass for COVID vaccination.

This particular initiative was tested successfully by Singapore Airlines, and more than 20 carriers, the minister said.

“In recent months, Singapore has announced that it will accept visitors who use a mobile travel passes containing digital certificates for Covid-19 tests and vaccines,” Mbalula said.

“This makes Singapore one of the first countries to adopt this initiative. Singapore will accept the IATA mobile travel pass for pre-departure checks, where travellers can get clearance to fly to and enter Singapore by showing a smartphone application containing their data from accredited laboratories.”

The IATA’s app allows travellers to store digital information from certified labs. It will be available for download later this month. IATA aims to bring in additional changes such as QR code scanning by immigration officers.

Vaccine passports have been the subjects of debates over equitability, access and potential for abuse. However, vaccine passports are not only permissible under international health regulations, they already exist. The World Health Organization endorses certificates confirming vaccination against yellow fever for entry into certain countries. They also incentivise vaccination, a public good.

Currently, South Africa has 62 ‘major restrictions’ from other countries in place, with suspended travel, stringent requirements for entry or outright bans. Meanwhile there are 92 moderate restrictions in place on South Africa, where travel is possible subject to measures such as COVID tests on arrival.

Source: BusinessTech

Categories : COVID VaccinesTags :

Second Gen COVID Vaccine Considered for Booster Shot in SA

On By ModernMedia
Image source: Pexels/CC0

A second generation viral vector COVID vaccine candidate from ImmunityBio Inc is being considered as a booster shot in a study involving nearly 500 000 South African health workers already innoculated with the Johnson & Johnson vaccine.

The health workers, who are the first outside of much smaller studies to receive vaccinations in South Africa, will need a booster, Glenda Gray, the co-lead of the South African studies, said in an interview Wednesday.

“It could be the universal boost that we are looking for,” she said. “Hopefully we will start in a couple of weeks.”

ImmunityBio’s second generation COVID vaccine candidate uses an hAd5 virus as vector. It induces both short term and long term immunity, and besides targeting the coronavirus’ spike proteins like first generation vaccines, it also targets the nucleocapsid protein, which has a lower rate of mutations. Additionally, this hAd5 vector virus provokes an anti-SARS-CoV-2 response, even in individuals with adenovirus immunity.

The magnitude of this T cell response was equivalent to those seen for spike and nucleocapsid T cell responses from previously infected convalescent SARS-CoV-2 patients.

The robust T cell response to both proteins could make it more effective against strains such as the B.1.351 ‘South African’ variant , ImmunityBio said in a statement earlier this year.

The vaccine is also being assessed to determine the safety and effectiveness of oral, sublingual and subcutaneous administration routes.

ImmunityBio’s vaccine is currently in phase I trials in Cape Town, and the company has signed an agreement with South Africa’s BioVac Institute to produce the inoculation in the country should it win approval.

Source: BusinessTech

Categories : COVID GeneticsTags :

SARS-CoV-2 Does Not Alter Human DNA

On By ModernMedia
Image source: Pixabay

Despite controversial claims, the SARS-CoV-2 virus likely does not integrate its genetic material into the genes of humans, according to a study published in the Journal of Virology.

A prior study reported the virus’s genetic material was found to have integrated into human DNA in cells in petri dishes, though the scientists conducting the newer research now say this was resulted from genetic artefacts in the testing.

Study co-lead author Majid Kazemian, a Purdue University assistant professor of biochemistry and computer science, said that this finding has two important implications.

“Relatively little is known about why some individuals persistently test positive for the virus even long after clearing the infection,” he explained. “This is important because it’s not clear whether such individuals have been re-infected or whether they continue to be infectious to others. So-called ‘human genome invasion’ by SARS-CoV-2 has been suggested as an explanation for this observation, but our data do not support this case.

“If the virus was able to integrate its genetic material into the human genome, that could have meant that any other mRNA could do the same. But because we have shown that this is not supported by current data, this should allay any concerns about the safety of mRNA vaccines,” he concluded.

It is indeed possible for virus genetic material to be incorporated into the DNA of humans and other animals, which are referred to as ‘chimeric events’. These have happened over many millions of years; human DNA contains approximately 100 000 pieces of ‘fossil DNA’ from viruses that have been accumulated throughout our evolution, accounting for nearly 10% of the genetic material in our cells. Some viral fragments even play a role in diseases such as cancer.

Recent scientific journal articles have raised controversy by claiming that the SARS-CoV-2 virus can also cause these chimeric events. Even before this study demonstrated it was not the case, the researchers suspected it was unlikely, said co-lead author Dr Ben Afzali, an Earl Stadtman Investigator of the National Institutes of Health’s National Institute of Diabetes and Digestive and Kidney Diseases.

“While an earlier study suggested that, in cells infected with SARS-CoV-2, genetic material from the virus copied and pasted itself into human DNA, our group thought this seemed unlikely,” Dr Afzali said. “SARS-CoV-2, like HIV, has its genetic material in the form of RNA but, unlike HIV, does not have the machinery to convert the RNA into DNA. SARS-CoV-2 is unlikely to paste itself into the genome and coronaviruses, in general, does not go near human DNA. As our study shows, we find it highly improbable that SARS-CoV-2 could integrate into the human genome.”

Christiane Wobus, associate professor of microbiology and immunology at the University of Michigan Medical School, another co-lead author on the study, said that the collective understanding of RNA viruses is that SARS-CoV-2 integrating into the human genome was extremely unlikely, it was still worth asking the question.

“Unexpected findings in science—when confirmed independently—lead to paradigm shifts and propel fields forward. Therefore, it is good to be open-minded and examine unexpected results carefully, which I believe we did in our study,” she said. “However, we did not find conclusive evidence for SARS-CoV-2 integration, but instead showed that during the RNA sequencing methodology, chimeras are produced at a very low level as an artifact of the laboratory technique.”

To examine any possible integration event, the researchers came up with a novel technique involving extraction the genetic material from infected cells and then boosting the amount of the genetic material 30-fold. With any chimeric events in the host cell DNA, these bits of genetic material from SARS-CoV-2 would have also increased those by 30. The data did not show this.

“We found the frequency of host-virus chimeric events was, in fact, not greater than background noise,” Kazemian stated. “When we enriched the SARS-CoV-2 sequences from the bulk RNA of infected cells, we found that the chimeric events are, in all likelihood, artifacts. Our work does not support the claim that SARS-CoV-2 fuses or integrates into human genomes.”

Source: Medical Xpress

Journal information: Bingyu Yan et al, Host-virus chimeric events in SARS-CoV2 infected cells are infrequent and artifactual, Journal of Virology (2021). DOI: 10.1128/JVI.00294-21

Categories : COVIDTags :

School Closures in NC and All School Contact Sports Suspended

On By ModernMedia

As South Africa awaits an impending third wave, twenty-eight schools in the Northern Cape have had to close as a result of COVID cases this month, while all school contact sports are being suspended.

While infections are on the rise in most provinces, Northern Cape has 314 patients in hospital with COVID, according to information from the National Institute for Communicable diseases.

“Since 1 May we can report that 28 schools in the Province have been directly affected due to COVID-19 cases,” the department said in a statement on Wednesday.

The department said that those schools were closed for disinfecting and those who were infected with COVID were isolated.

“To date, 13 schools still remain closed and will reopen once it is safe to do so. The department also recorded from 1 May to date, 124 positive cases that were reported at schools thus impacting on valuable learning and teaching time being lost.”

Four schools in the small town of Calvinia were also closed earlier this year to contain rapidly spreading COVID infections.

The provincial education department’s Geoffrey van der Merwe called on communities to be even more vigilant and follow COVID safety protocols.

“District offices developed recovery plans for these schools to ensure that the academic performance of learners are not negatively affected,” he said.

Since the second phase of the programme kicked off this week, a mere 329 people in the province have so far received a COVID vaccine shot. So far approximately 9500 healthcare workers in the Northern Cape have been vaccinated.

No more rugby

Meanwhile, all contact sport at South African schools has been suspended with immediate effect.

This was decided on by the Council of Education Ministers  in a virtual meeting held on Wednesday morning .

However, the Department of Basic Education said non-contact sport training in schools could continue, on the condition that all social distancing, hygiene and safety measures would be adhered to and that there was no physical contact between participants during training.

Source: Eyewitness News