Category: COVID

Categories : COVIDTags :

Department of Health COVID Vaccine Rollout Phase 2 Outlined

On By ModernMedia

The Department of Health’s COVID vaccine rollout has been fleshed out in a presentation, including details on how the vaccines will be distributed, and the jobs earmarked for the shots.

A presentation from the department indicates that the government has secured around 51 million vaccine doses, with 20 million from Pfizer and 30 million from Johnson & Johnson (J&J). However, it is unclear how the current pause in J&J administration in South Africa due to concerns about rare blood clots will affect immunisation schedules.

However, health minister Dr Zweli Mkhize announced that South Africa has secured a further 10 million Pfizer vaccines.

“We can now guarantee that the number of people that will be vaccinated with Pfizer has increased from 10 to 15 million,” he said.

With the 30 million of the single-dose shots from J&J, the current planned rollout will cover about 45 million South Africans.

Dr Mkhize said that both the Pfizer and J&J agreements cost around $10 (R145) per vaccine, with non-refundable clauses.

“The agreements state that down-payments that have been made in advance by the department shall not be refundable by the manufacturer to us in any circumstances. This is another onerous term that we had to settle for,” Dr Mkhize told the committee.

Meanwhile, government was sent an email from J&J, which stated that the company will not sign off the 20 million doses until they receive a letter from the Trade, Industry and Competition Minister, expressing support for the local investment that they made in Aspen Pharmacare.

“We’ve been taken aback by this, as there are clauses in the agreement that express this support and acknowledge that this production will not just be limited to South Africa and the continent, but also targeted for the global market,” said Dr Mkhize.

The department indicated that the Pfizer vaccine will likely go to major metropolitans due to its larger pack size and refrigeration requirements, while the J&J vaccine with its less stringent refrigeration needs would be allocated to rural areas.

South Africa’s Phase 2 of the vaccine rollout is planned to begin in May and run until October, with essential workers over 40 and the elderly to be targeted in the programme. This is to include a focus on old age homes and care facilities, plus identifying those with co-morbidities.

The department provided an overview of occupations covered under the vaccine rollout, to include, among others, the police, army, social and municipal workers, and faith and traditional leaders. Private sectors could include mining, retail, transport, and manufacturing.

Source: BusinessTech

Categories : COVIDTags :

FDA and CDC Justify J&J Vaccine Pause

On By ModernMedia

FDA and CDC officials recommended pausing administration of the Johnson & Johnson COVID vaccine “out of an abundance of caution,” and mainly for the benefit of clinicians to respond to associated serious events.

This comes after six cases of cerebral venous sinus thrombosis (CVST) combined with thrombocytopenia were reported in the US, all among women ages 18-48. With approximately 6.8 million doses administered in the U.S., it suggests a one-in-a-million risk. 

J&J has halted distribution of its vaccine in Europe, reportedly taking officials there by surprise. South Africa has also paused the vaccine rollout.

At a media briefing, when asked whether pausing administration of the vaccine was an “overreaction,” Acting FDA Commissioner Janet Woodcock, MD, said the aim was to provide “time for the healthcare community to learn what they needed about how to diagnose, treat, and report” such events.

FDA’s director for the Center for Biologics Evaluation and Research, Peter Marks, MD, PhD, noted that the condition involves a rare blood clot for which heparin or related anticoagulants is not the standard treatment.

“The issue with these types of blood clots is if one administered standard treatment, one can actually cause tremendous harm or the outcome can be fatal,” he said. “One needs to make sure providers are aware if they see people with low blood platelets or blood clots, to inquire about recent vaccination and act accordingly.”

The background rate of CVST is 2-14 per million in the setting of a normal platelet count, but thrombocytopenia together with abnormal clotting makes it a “pattern.” CVST symptoms also include severe headache, abdominal pain, leg pain, and shortness of breath.

Marks noted that vaccination-related headaches tend to resolve within a few days, whereas CVST symptoms could manifest over a week post-vaccination, and closer to a patient presenting to the emergency department with severe headache. No such rare events have been seen more than 3 weeks post-vaccination.

Dr Marks also said that this pause is a recommendation but does not prevent healthcare providers from providing the J&J vaccine to their patients should benefits of vaccination outweigh the risks.

“We’re not going to stop a provider from administering a vaccine,” he added. “The benefit/risk will be beneficial overall to that individual in a large majority of cases.”

Dr Marks said that while they don’t have a “definitive cause” for the adverse reactions, data from AstraZeneca on similar events in Europe, it is likely a “similar mechanism” with the J&J vaccine. An autoantibody against platelet factor 4 has recently been identified as the trigger for the reaction.
“The immune response occurs rarely after some people receive the vaccine, and that immune response leads to the activation of platelets and extremely rare blood clots,” he said.

However, Marks stopped short of calling it a “class effect,” meaning it was related to the viral vector vaccine itself. He said he wasn’t ready to make a “broad statement yet,” but “obviously it’s from the same general class of viral vectors.”

The AstraZeneca, J&J and Sputnik V vaccines all use adenovirus vectors to deliver antigens. The rate CVST for AstraZeneca was estimated by European officials to be about 5 per million doses. Though Sputnik V has no confirmed CVST cases, a recent report suggests a possibility.

Besides these, the Ebola vaccines are the only other ones to use adenovirus vectors.
Woodcock said that all US cases were in women of reproductive age, with one death and one hospitalisation, but Marks said it was not clear there was any association with hormonal contraception, which also carries a small thrombosis risk. The cases did not have any preexisting conditions which could have explained the events.

The American College of Obstetricians and Gynecologists (ACOG) noted there is no “clear phenotype” for women who may experience this complication.

“Until there is a better understanding of the frequency and impact of this finding, it will be important to encourage pregnant and postpartum women who wish to be vaccinated to receive the mRNA vaccines: Pfizer or Moderna,” said Christopher Zahn, MD, vice president for practice activities at ACOG, in a statement.

“If venous thrombosis is noted in the setting of thrombocytopenia, treatment includes intravenous immunoglobulin and other supportive care,” Dr Zahn added.

Source: MedPage Today

Categories : COVIDTags :

US Hits Pause on J&J Vaccine

On By ModernMedia

Reacting to reports of potentially dangerous blood clots, the US is recommending a “pause” in immunisations with the single-dose Johnson & Johnson COVID vaccine in order to perform investigations.

The Centers for Disease Control and Prevention and the Food and Drug Administration said in a joint statement that they were investigating blood clots in six women that occurred 6 to 13 days after vaccination. The clots, seen in the sinuses of the brain, also had lowered platelet counts. This renders the use of heparin, the standard treatment for blood clots, potentially dangerous.

Out of 183.5 million vaccine doses administered in the US, over 6.8 million doses are the J&J vaccine — the overwhelming majority without serious side effects. The rest is made up by the two other authorised vaccines, from Moderna and Pfizer.

Use of the J&J shot will be paused in US federal distribution channels, including mass vaccination sites, with states and other providers being expected to follow.

CDC’s Advisory Committee on Immunization Practices will meet Wednesday to discuss the cases and the FDA has also launched an investigation into the cause of the clots and low platelet counts.

“Until that process is complete, we are recommending a pause in the use of this vaccine out of an abundance of caution,” Dr Anne Schuchat, principal deputy director of the CDC, and Dr Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said in a joint statement.

They recommend that people who received the J&J vaccine and are experiencing severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after receiving the jab contact their health care provider.

Officials say that they want to bring healthcare providers up to speed on the blood clot’s “unique treatment” .

Meanwhile, Johnson & Johnson had said it was aware of the blood clot reports, but no association with its vaccine had been established.

“We are aware that thromboembolic events including those with thrombocytopenia have been reported with Covid-19 vaccines,” the company said in a statement. “At present, no clear causal relationship has been established between these rare events and the Janssen Covid-19 vaccine.”

In late February, the FDA  granted emergency use authorisation to the J&J vaccine, with hopes that its single-dose and relatively simple storage requirements would speed vaccinations across the country. However, only a fraction of the vaccines administered in the US are the J&J shot. The company has been beset by production delays and manufacturing errors at a contractor’s plant. 

The pharmaceutical company took over the facility to ramp up production to make good on its promise to the US government of 100 million doses by the end of May. Only about 9 million of the company’s doses have been delivered to states and are awaiting administration, according to CDC data.
Previously, concern over the blood clots was confined to AstraZeneca’s vaccine, with European regulators saying last week they found a possible link between the shots and an exceedingly rare type of blood clot presenting with low platelets, a situation found more commonly in young people.

Nevertheless, the European Medicines Agency emphasised that the benefits for the vaccine outweigh the risks. Despite this, several countries imposed restrictions on vaccine eligibility and some such as Britain and Greece recommending that people under a certain age be offered alternatives.

Unlike the Pfizer/BioNTech and Moderna vaccines which use mRNA to train the immune system to recognise the SARS-CoV-2 spike protein, the J&J and AstraZeneca vaccines use an adapted adenovirus to introduce the spike protein antigen into the body. Adenoviruses were first identified in the 1950s as a family of similar disease-causing viruses. AstraZeneca’s vaccine uses a chimpanzee adenovirus while the J&J uses a human one.

Source: Medical Xpress

Categories : COVIDTags : 1 Comment

Blood Clotting Concerns Resulting in Vaccination Delays

On By ModernMedia

Vaccination programmes are facing increasing delays because of concerns over AstraZeneca’s very rare blood clotting incidents.

Australia and Greece are the latest governments deciding to offer young people alternatives to AstraZeneca’s vaccine. This will delay inoculation campaigns by around a month in Australia, France and Britain. Meanwhile, the World Health Organization said most countries lacked vaccines to cover health workers and others at high risk from exposure to the virus.

WHO Director-General Tedros Adhanom Ghebreyesus said high income countries had on average vaccinated one in four people whilst low income countries the figure was one in over 500.

“There remains a shocking imbalance in the distribution of vaccines,” he told a press briefing on Friday.

The WHO and GAVI vaccine alliance’s COVAX mechanism seeks to secure vaccines for poorer nations. GAVI alliance head Seth Berkley said AstraZeneca’s supply chain had in fact “picked up” when asked whether the vaccine was being shunned.

“As countries decide they are going to prioritise one vaccine or another, that may free up doses, and in so doing we will try to make sure those doses are made available without delay, if countries are willing to make that happen,” he said.

Australia doubled its orders for Pfizer after its health body recommended that people under 50 receive an alternative vaccine. Greece followed Britain’s example in recommending that people under 30 seek an alternative jab.

AstraZeneca said it was working with regulators “to understand the individual cases, epidemiology and possible mechanisms that could explain these extremely rare events”.

Sabine Straus, chair of the EMA’s safety committee, said that the European Medicines Agency (EMA) received reports of 169 cases of the rare brain blood clot by early April, after 34 million doses had been administered.

Most of the cases reported had occurred in women under 60.

On Friday, the EMA said that if a causal relationship is confirmed or considered likely, regulatory action will be needed to minimise risk. It is also investigating Johnson & Johnson’s (J&J) vaccine over reports of blood clots. US infectious disease expert Anthony Fauci however said there were no red flags reported for the J&J vaccine.

The AstraZeneca vaccine is the cheapest and most high-volume vaccine to date to curb the pandemic and avert damaging lockdowns, but supplies have been beset by delays.

However, new data in the EU, beset by delays, showed that the pace of vaccine deliveries was picking up. Germany said it was accelerating inoculations but needed a new lockdown as well.

“Every day in which we don’t act, we lose lives,” Lothar Wieler, president of the Robert Koch Institute, said.

Hong Kong Health Secretary Sophia Chan said the city would defer its order of the AstraZeneca vaccine this year “so as not to cause a waste when the vaccine is still in short supply globally”, adding that the government was considering buying a new, more effective type of vaccine.

All the countries recommending age limits for the AstraZeneca shot have emphasised that its benefits far outweigh the risks of catching COVID for older people. Even so, some people have been put off; in Madrid half of over 60s meant to receive the AstraZeneca vaccine turned up, a day after Spain’s recommendation that younger people get a different shot.

In France, where vaccine hesitancy is high, the top health body recommended that those over 55 who had received a first dose of the AstraZeneca shot get a new-style messenger-RNA vaccine for the second one: either the Pfizer/BioNTech one or Moderna’s.

Source: Reuters

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South African Variant Escapes Pfizer Vaccine More Easily

On By ModernMedia

The South African variant escapes protection of the Pfizer/BioNTech vaccine better than other forms of the virus, Israeli experts said Sunday.

The study by Tel Aviv University and Clalit Health Services, Israel’s largest healthcare provider, compared patients with COVID, 400 unvaccinated patients to 400 partially or fully vaccinated ones.

Less than one percent of COVID cases in Israel were due to the South African variant. However, among the 150 people who were fully vaccinated yet had developed COVID, “the prevalence rate [of the B.1.351 variant] was eight times higher than the rate in the unvaccinated [individuals],” the authors wrote.

“This means that the Pfizer-BioNtech vaccine, though highly protective, probably does not provide the same level of protection against the South African (B.1.351) variant of the coronavirus,” the authors added.

“The South African variant is able, to some extent, to break through the vaccine’s protection,” said professor Adi Stern of Tel Aviv University’s Shmunis School of Biomedicine and Cancer Research, one of the study’s authors.

Prof Stern said that the study did not assess whether the eight people infected with the South African developed severe COVID.
“Since we found a very small number of vaccinees infected with B.1.351, it is statistically meaningless to report disease outcomes,” he said.

The possibility of reduced protection was already hinted at in two studies conducted by principal vaccine manufacturers Pfizer/BioNTech and Moderna, showing that the presence of antibodies after vaccination was less pronounced in people exposed to the B.1.351 variant. This marked the first real-world assessment of B.1.351’s ability to bypass a vaccine.

Israel’s vaccination campaign has seen 5.3 million people receive a first dose, while 4.9 million, or 53 percent of the population, have had two shots. 

Clalit’s earlier study on 1.2 million Israelis found that the Pfizer/BioNTech jab gave 94 percent protection against COVID.

Israel has eased many of its restrictions since its vaccine rollout, but various measures remain in place including mask-wearing and a “green passport” system that allows vaccinated people access to certain locations. With cases down 97% since January, Israel may have achieved “herd immunity”, according to Eran Segal, a computational biologist at the Weizmann Institute of Science.

Ran Balicer of Clalit said inoculations, plus mask-wearing and other safety measures had likely helped contain the B.1.351 variant, despite its apparent ability to break through the Pfizer/BioNTech vaccine.

A combination of all these factors “are most likely… preventing the virus strains, including the South African one, from spreading” significantly in Israel, he said.

“As we taper down the non-pharmaceutical interventions, we must do so gradually to ensure we do not cross a threshold that would enable these variants to spread.”

Source: Medical Xpress

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Liquor Industry Questions Alcohol Ban Effectiveness

On By ModernMedia

Representatives from the liquor industry have said that the South African government must consider data from a new report that shows little alcohol ban effectiveness on trauma cases. However, other studies show negative effects of alcohol during lockdown, and a surge in violent trauma in Cape Town after alcohol bans were lifted.

In a statement on Thursday, the South African Liquor Brand owners Association (Salba) referenced a new report showing that, compared to other countries, South Africa saw similar trauma cases with its lockdown and alcohol ban to those that only had a lockdown.

The report had financial support from Distell, led by independent data expert Ian McGorian of Silver Fox Consulting, in collaboration with professor Mike Murray from the University of KwaZulu-Natal.

The report found that trauma cases in South Africa under lockdown dropped 60%. But other countries also saw the same drop with no alcohol ban, including the UK (57%), Ireland (62%), Italy (56.6%) and the USA (54%), casting doubt over the effectiveness of alcohol bans in curbing trauma. The researchers also commented that curfews may have explained more of a reduction in trauma cases than alcohol bans.

While members of the liquor industry recognised the impact of alcohol on South African society, they said that government needs to be more objective with its lockdown regulations.

Salba chairperson Sibani Mngadi said the alcohol ban over Easter Weekend, while simultaneously allowing larger gatherings, made even less sense in reducing COVID transmission. This suggests that government was not considering science in its decision making, he said.

However, a multicentre study from Colorado, USA showed that even while trauma cases during lockdown fell by 33%, alcohol screens increased from 34% to 37%, and alcohol positive patients rose from 32% to 39%.

A study of Cape Town trauma admissions saw a dramatic drop of 53% in trauma admissions during the hard lockdown and an immediate rebound coinciding with the resumption of alcohol sales, with a 107% increase in gunshots wounds compared to pre-lockdown conditions.

The researchers noted that in South Africa the trauma demographic is much younger, with much higher rates of violence, with about half of homicide victims in SA testing positive for alcohol.

Distell chief executive Richard Rushton said the industry was merely asking that the data should be viewed objectively to improve dialogue with decision makers.

“We are all on the same side, and we want to help find solutions. We are very clear that alcohol abuse is unacceptable and causes harm. Our view is that the focus must be on finding ways to deal with high-risk drinkers, rather than using blunt instruments that penalise all South Africans.

“Any proposed new regulations need to be evidence-based, rational and target problem areas,” he said.

Business Leadership SA chief executive Busisiwe Mavuso said that lockdown could have been better managed, as 220 000 jobs had been lost along billions of rands in tax to the fiscus, while uncertainty still plagued alcohol producers.

“The decisions made to confront the health crisis should not have unintended consequences for the economy, and that is exactly what has happened with the bans on alcohol,” she said.

Mr Mavuso added that, since the start of the pandemic, business has been a willing partner to government and “needs to be part of the solution to ensure we fight this pandemic with the least possible damage to the economy”.

“The data analysis by the alcohol industry is an important intervention and must be taken seriously as we move forward.”

Source: BusinessTech

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Smartphone Tracking in COVID Shows Movement Linked to Case Rise

On By ModernMedia

According to a new study which used mobility tracking of cell phone data, a greater movement of people is a strong predictor of increased COVID cases rates.

Until people are widely vaccinated against SARS-CoV-2, the array of nonpharmaceutical public health interventions such as physical distancing and limiting travel and social contacts will remain the most effective means of controlling COVID. Capturing the interrelationship between human behaviour and infectious diseases is one of the hardest problems in epidemiology.

“Mobility measures capturing human activity through anonymized tracking of smartphones are believed to be reasonable proxies of contact rates outside of one’s own home; these measures can provide more timely and reliable sources of information on contact rates compared with time-use surveys or contact tracing,” the authors wrote.

Researchers looked at anonymised smartphone mobility data from nearly 12 months from March 2020 to March 2021, both at a national and provincial level, while controlling for date and temperature. A 10% increase in the mobility of Canadians outside their homes was found to be associated with a 25% increase in subsequent SARS-CoV-2 weekly growth rates. They investigated at the mobility threshold (the level needed to control the virus) and the mobility gap (the difference between the threshold and actual movement).

“The mobility threshold and mobility gap can be used by public health officials and governments to estimate the level of restrictions needed to control the spread of SARS-CoV-2 and guide, in real-time, the implementation and intensity of nonpharmaceutical public health interventions to control the COVID-19 pandemic,” wrote the authors.

Source: News-Medical.Net

Journal information: Brown, K. A., et al. (2021) The mobility gap: estimating mobility thresholds required to control SARS-CoV-2 in Canada. Canadian Medical Association Journal. doi.org/10.1503/cmaj.210132.

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South African Volunteers Battle Vaccine Misinformation

On By ModernMedia
Man with LED mask reading a burning newspaper. Photo by Connor Danylenko from Pexels.

As the long-delayed vaccine rollout in South Africa has begun, the government has run a public campaign to tackle prevalent health myths. But there are also volunteers who are waging an online battle against COVID and vaccine misinformation, as reported by the BBC.

Sarah Downs, who is studying molecular biology and infectious diseases, debunks false claims under the alias Mistress of Science and is fighting a surge of misinformation in South Africa. A relatively small collection of Facebook groups and users are responsible for promoting this misinformation. When she tweeted about her grandmother’s passing, a COVID denier questioned whether an autopsy had been performed. 
“We estimate that it’s about 20 000 South Africans who are actually active on anti-vax Facebook pages,” said Prof Hannelie Meyer, a pharmacist and adviser to the South African Vaccine and Immunisation Centre (Savic).

Most anti-vaccine claims in South Africa actually originate in the United States, according to a 2015 study. Anecdotal evidence, such as the spread of false claims about vaccines and DNA by an American osteopath, show this trend still holds in the pandemic.

Prof Meyer said that while data on vaccine hesitancy in SA are limited, studies indicate that more wealthy and educated groups, particularly among whites, are less willing to be vaccinated.

Leading virologist Prof Jeffrey Mphahlele has also pushed back against rumours, such as COVID and its vaccines being a Western plot to reduce Africa’s population and control its natural resources. He called the misinformation “mind boggling” – pointing out the supposed plot would require the West to create a virus that killed millions of its own people.

Even authority figures have promulgated falsehoods: South Africa’s top judge was recently criticised after a video showed him linking vaccines to a “Satanic agenda.”

One of the most prominent groups on Facebook, with some 10 000 members, seeks to spread “awareness” about vaccines but the members’ hard-line anti-vaccine attitude is very clear, ridiculing or dismissing vaccines. One video posted in the group – originally aired on an evangelical US Christian television programme – suggested getting a jab could lead to “a lifetime of illness”.

Sarah Downs stepped in to help answer questions amidst the deluge of misinformation, and one person she helped was Sheona Lottering, a swimming teacher.

“I had a friend that forwarded me a German article,” Sheona said. “She was trying to convince me that death was one of the side-effects [of a COVID vaccination].

“And I was a little bit freaked out about that.”

Sarah explained the subtleties around adverse events to her, and now Sheona keeps in contact with Sarah over difficult vaccine-related questions.

Lisa (not her real name) spends hours lurking in Facebook groups to guide people towards trusted sources of health information.

“The claims are so bizarre I could hardly believe there are people believing these things,” she said. “I don’t like misinformation, so when I see something, I just try to correct it.”

Doing this for over a decade, she’s seen communities grow and knows their tactics. She said that young mothers are a particular target in Facebook groups, where posts are coordinated to try and convince them not to vaccinate their children., which is when Lisa steps in. She keeps her inbox open and believes gentle communication works best – asking about people’s concerns rather than shouting statistics at them.

But Sarah, Lisa and other volunteers we spoke to risk exposing themselves to online abuse, and the prospects of persuasion can often seem slim. It’s difficult, pro-health work – that isn’t paid. So do they judge success?

“I think if I can just help one person be a little bit less terrified… that’s what I aim to get out of it,” Sarah says. “And if they’re willing to take the vaccine, even more so.”

Source: BBC News

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South African Variant Escapes Sputnik Vaccine

On By ModernMedia

A study on COVID variants using in vitro tests, available on the preprint server medRXiv, has shown that the South African variant escapes the Sputnik V vaccine.

This study is the first of its kind to show Sputnik V vaccine recipients had reduced neutralising capacity against the B.1.351 and E484K mutant spikes.

When it comes to vaccine design, the most effective vaccines use a stabilised form of the spike protein, while others use the wildtype spike, protecting against severe disease but not infection because of lower levels of neutralising antibodies. A number of SARS-CoV-2 variants of concern (VOC) have mutations on the spike protein, or the E484K mutation, which allows it to escape vaccines and prior immunity. 

In South Africa, where 93% of infections are due to B.1.351, the AstraZeneca vaccine, based on the wild-type spike, failed to prevent mild-to-moderate COVID. The Sputnik V or Gam-COVID-Vac vaccine is also based on the wild-type spike. Interim Phase 3 trial results reported an efficacy of 92%, but this excludes current variants and any lineage containing E484K. 
The current study examined serum neutralisation activity in samples obtained from 12  recipients of the Sputnik V vaccine in Argentina. This country has already detected many independent variants with E484K, with or without N501Y substitutions.

The researchers found that pseudoviruses bearing either the wildtype D614G spike, and the B.1.1.1.7 spike were effectively neutralised by the vaccine sera, in live virus plaque reduction neutralisation assays. The geometric mean titer of neutralising titers was 49, similar to that of the phase III trial.

However, these sera showed moderate to a marked reduction in neutralisation titers against spike protein bearing E484K, and the UK variant. Even at the highest serum concentration used, 9 of the 12 serum samples could not inhibit 50% of B.1351 viral particles, and only half the sera did so against the E484K mutant.

The researchers concluded that, relative to the wildtype spike virus neutralising titers, were reduced by seven-fold against the B.1.351 lineage and three-fold against the E484K spike. They also found that the VOCs with the different spikes showed different modes of escape from antibody-mediated neutralisation by sera elicited by the Sputnik V vaccine. This means that resistance to neutralisation offered by the South African variant occurs by a different mechanism than that of the E484K mutant.

The UK VOC has low resistance to pre-existing or vaccine-induced antibodies, but the B.1.351 variant shows marked resistance. In fact, 8 of 12 samples were unable to reach IC90 at the highest possible serum concentration.

One neutralised the UK variant but none of the other three variants. These findings are of particular concern because all three VOCs carry the N501Y RBD substitution that confers increased affinity for the ACE2 receptor.

This resistance is competitive and is not present at higher serum concentrations. However, this is not true for the mutations in the B.1.351 variant, which escapes neutralisation with undiluted serum.

Though the Sputnik V vaccine likely protects against severe COVID from VOCs, it is troubling that B1.351, as well as all E484K-bearing mutants, is resistant to neutralisation by sera elicited by this vaccine.

However, antibody functions may be different in vivo, and this study does not cover cell-mediated immunity to multiple antigen sites.
“Taken together, our data argue that surveillance of the neutralizing activity elicited by vaccine sera will be necessary on an ongoing basis,” the authors wrote.

The knowledge of which variants can still spread among vaccinated and naturally immune individuals will help decide how to contain them with vaccine upgrades.

Source: News-Medical.Net

Preprint information: Ikegame, S. et al. (2021). Qualitatively distinct modes of Sputnik V vaccine-neutralization escape by SARS-CoV-2 Spike variants. medRxiv preprint. doi: https://doi.org/10.1101/2021.03.31.21254660. https://www.medrxiv.org/content/10.1101/2021.03.31.21254660v2

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COVID Surges Driven by New Variants

On By ModernMedia

A study of SARS-CoV-2 genomes and epidemic case data has shown that COVID outbreaks emerge with new variants.

“As variants emerge, you’re going to get new outbreaks,” said Bart Weimer, professor of population health and reproduction at the UC Davis School of Veterinary Medicine. The study combined classical epidemiology with genomics, providing a tool for public health authorities to predict the course of pandemics.

SARS-CoV-2  only has 15 genes, but is mutating constantly. The majority of these changes have little impact, but occasionally they result in the virus becoming more or less transmissible.

Together with graduate student DJ Darwin R Bandoy, Prof Weimer at first analysed the genomes of 150 SARS-CoV-2 strains, mostly from outbreaks in Asia prior to March 1, 2020, along with epidemiology and transmission information on those outbreaks. 

The classified outbreaks by stage: index (no outbreak), takeoff, exponential growth and decline. Virus transmissibility is set by the value R, or reproductive number, where R is the average number of new infections caused by each infected person.

They combined all this information into a metric called GENI, for pathogen genome identity. Comparing GENI scores with epidemic phases showed that an increase in genetic variation immediately preceded exponential growth in cases, for example in South Korea in late February. In Singapore, however, bursts of variation were associated with smaller outbreaks that were quickly brought under control.

Prof Weimer and Bandoy then looked at 20 000 sequences of SARS-CoV-2 viruses collected over February to April 2020 in the United Kingdom, and compared them with COVID cases data.

They found that the GENI variation score rose steadily with the number of cases. When a national lockdown was imposed in late March, the number of new cases stabilised but the GENI score continued to rise. This shows that control measures such as banning gatherings, mask mandates and social distancing are effective in controlling spread of disease in the face of rapid virus evolution.

It could also help explain “superspreader” events when large numbers of infections result from relaxed precautions at an event.

Prof Weimer said he hopes that health authorities will adopt this method of measuring virus variation and linking it to the local transmission rate, R.

“In this way you can get a very early warning of when a new outbreak is coming,” he said. “Here’s a recipe for how to go about it.”

Source: Medical Xpress

Journal information: Scientific Reports (2021). DOI: 10.1038/s41598-021-86265-4