Geneva: While there have been a few cases of new Omicron sub-variants BA.4 and BA.5, so far there is no change seen in the severity or transmissibility, the World Health Organisation has said.The new sub-variants have to date been detected in South Africa, Botswana, Belgium, Germany, Denmark, and the UK. The global health agency earlier said that it is keeping a track of the new variants."There are less than 200 sequences available so far and we expect this to change...We are tracking (the virus) very closely to see if there is any uptick in case detection, but (so far) we haven't seen any change in epidemiology or severity," WHO lead epidemiologist Dr. Maria Van Kerkhove said at a press event on Wednesday.The global health agency said it had begun tracking the two sub-variants because of their "additional mutations that need to be further studied to understand their impact on immune escape potential". In its latest weekly epidemiological update, the WHO noted that the number of new Covid-19 cases and deaths continues to decline. During the week of April 4-10 for a third consecutive week, more than 7 million cases and over 22,000 deaths were reported, a decrease of 24 per cent and 18 per cent, respectively, as compared to the previous week."On Covid-19, there's good news. Last week, the lowest number of Covid-19 deaths was recorded since the early days of the pandemic," WHO Director General Tedros Adhanom Ghebreyesus told a press briefing in Geneva on Wednesday.However, the agency warned that lower case numbers and deaths do not necessarily mean 'lower risk' as the pandemic continues to remain a public health emergency.Ghebreyesus advised countries to be prepared to scale up Covid-19 response rapidly.He reiterated that higher testing and sequencing rates are vital for scientists to track existing variants and to identify new ones as they emerge."At present there are a number of Omicron sub-lineages we're following closely, including BA.2, BA.4 and BA.5 and another recombinant detected, made up of BA.1 and BA.2", he said.WHO's director of emergencies, Michael Ryan, warned that as the virus continues to evolve, the world "cannot simply afford to lose sight of it"."It would be very short-sighted at this point to assume that lower numbers of cases mean absolute lower risks. We are pleased to see deaths dropping but this virus has surprised us before, it has caught us off guard before," he added.Meanwhile, WHO's lead scientist Dr. Soumiya Swaminathan, said that sub-lineages and recombinants will continue to appear, and the world must continue investing in improved tools such as new vaccines."We have to be prepared for the possibility that this virus can change so much that it might be able to evade existing immunity", she said.Ghebreyesus emphasised that currently, the virus remains deadly, especially for the unprotected and unvaccinated that don't have access to health care and antivirals.Besides getting vaccinated, he also advised people to continue wearing masks - especially in crowded indoor spaces and maintain good ventilation. The WHO chief also urged forA equitable distribution of Covid tools and strengthening of health systems."Bridging the vaccine equity gap is the best way to boost population immunity and insulate against future waves", he highlighted. —IANS

While there have been a few cases of new Omicron sub-variants BA.4 and BA.5, so far there is no change seen in the severity or transmissibility, the World Health Organisation has said.

No Change In Omicron BA.4, BA.5 Severity Or Transmissibility So Far: WHO

Tokyo: Japan's health ministry on Tuesday formally approved Novavax's Covid-19 vaccine, a fourth foreign-developed tool to combat the infections as the country sees signs of a resurgence led by a subvariant of fast-spreading omicron.The ministry approval comes the day after its experts panel endorsed use of Novavax's protein vaccine, which is designed with similar technology used to fight diseases such as the flu and hepatitis B, for the first two shots and a booster.Health Minister Shigeyuki Goto told reporters that Novavax product adds variety to the choices available and could appeal to those who are hesitant to use Covid-19 vaccines such as Pfizer's and Moderna's, which are designed with newer technologies.Jabs using Novavax vaccine are expected to start as early as late May.Japan reported 24,164 new cases Monday, according to the health ministry. Japan in March lifted all Covid-19 restrictions as the infections slowed significantly, but experts noted signs of a resurgence in a number of prefectures during a season of traveling and parties for people marking graduation and the start of the academic and business year.The government is trying to expand businesses and get the pandemic-hit economy back on track. Japan is slowly easing the border controls following sharp criticisms for its longtime restrictions on non-resident foreign students, scholars and business people, but Prime Minister Fumio Kishida has said Japan is not considering restarting inbound tourism anytime soon.Booster shots have been slow in Japan and less than 50% of the population had received booster shots of mainly mRNA vaccines from Pfizer and Moderna. A third vaccine, AstraZeneca, is hardly used due to public concern about reports of rare blood clotting and is largely donated to vaccine-scarce Asian countries bilaterally or through a United Nations-backed program. About 80% of the Japanese elderly population had received three shots.Goto said Japan has agreed to purchase 150 million doses of the Novavax shots developed by the Maryland company, which will help stabilize vaccine supply in a country that fully relies on foreign imports while development of its own vaccines have fallen behind. Novavax's distributor in Japan, Takeda Pharmaceutical Co., is to locally manufacture 250 million doses annually. —PTI

Japan's health ministry on Tuesday formally approved Novavax's Covid-19 vaccine, a fourth foreign-developed tool to combat the infections as the country sees signs of a resurgence led by a subvariant of fast-spreading omicron.

Japan Approves Novavax COVID-19 Vaccine

Japan's health ministry on Tuesday formally approved Novavax's Covid-19 vaccine, a fourth foreign-developed tool to combat the infections as the country sees signs of a resurgence led by a subvariant of fast-spreading omicron.





Jerusalem (The Hawk): The Omicron variants may burn themselves out in the next couple of months and the Delta variant might reemerge, BGU researchers warn in a new paper.&nbsp; Their findings were just published in the peer-reviewed journal Science of the Total Environment.&nbsp; While Delta wiped out the variants that preceded it, Omicron has not eliminated Delta, according to Prof. Ariel Kushmaro and Dr. Karin Yaniv. Prof. Kushmaro's lab team has developed sensitive arrays that can differentiate variants from each other in wastewater. Wastewater continues to give indications of where the coronavirus is active, even when PCR and rapid testing of people declines.&nbsp; They monitored Beer-Sheva's sewage from December 2021 to January 2022 and noticed this disturbing interaction between the Omicron and Delta variants. They also built a model with Prof. Rony Granek, which predicts that Omicron is burning itself out while Delta is just biding its time.&nbsp; "Of course, there are a lot of factors involved, but our model indicates there could be another outbreak of Delta or another coronavirus variant this summer," warns Prof. Kushmaro.&nbsp; Additional researchers included: Dr. Eden Ozer and Marilou Shagan from Ben-Gurion University, and Dr. Yossi Paitan from Ilex Labs. Prof. Kushmaro and his team are part of the School of Sustainability and Climate Change and the Avram and Stella Goldstein-Goren Department of Biotechnology Engineering.&nbsp; The research was supported by the BGU Coronavirus Challenge and the Israeli Ministry of Health.

 The Omicron variants may burn themselves out in the next couple of months and the Delta variant might reemerge, BGU researchers warn in a new paper. 

Israeli Researchers warn: The Omicron Variant did not totally eliminate the Delta, and the Delta Variant might return

Geneva: Omicron subvariants BA.4 and BA.5 have been detected in more than a dozen countries driving Covid outbreaks across the world, according to the World Health Organization.According to WHO's technical lead on Covid Maria Van Kerkhove, at least 16 countries have reported about 700 cases of BA.4, while more than 300 cases of BA.5 have been found across at least 17 countries, CNBC reported.The new sub-variants do not cause severe infection than the original Omicron strain, but they appear to be more contagious, Van Kerkhove was quoted as saying during a Q&amp;A on the organisation's social media platforms on Wednesday. She noted the WHO is monitoring BA.4 and BA.5 to determine if they will eventually overtake BA.2 as the dominant strain worldwide."We don't know how this variant will behave, how these sub-variants will behave in other countries that had a dominant wave of BA.2," Van Kerhkove said. "This is what remains to be seen."A recent study, not yet peer-reviewed, showed that BA.4 and BA.5 have the ability to avoid immunity induced by both previous Covid infection and vaccination. The findings by researchers from the Africa Health Research Institute in South Africa could signal a fresh wave of infections by the BA.4 and BA.5.Last week, a report by the UK Health Security Agency showed that South Africa reported the highest - 395 cases of BA.4 and 134 cases of BA.5 as of May 6.Other countries that detected the variants include Austria, UK, US, Denmark. Belgium, Israel, Germany, Italy, Canada, France, the Netherlands, Australia, Switzerland, Botswana, Portugal,A Belgium, Hong Kong, Canada, Israel, Norway, Pakistan, Spain and Switzerland, the report said.The report noted the number of sequences is low, but "the apparent geographic spread suggests that the variant is transmitting successfully." Van Kerkhove also mentioned another Omicron subvariant called BA.2.12.1, which has been detected in 23 countries. She said there are more than 9,000 reported sequences of the subvariant, most of which comes from the US, the report said.BA.2.12.1 made up about 42.6 per cent of all new cases in the U.S. during the week that ended on May 7, according to data from the Centres for Disease Control and Prevention.Van Kerkhove said that the higher growth rate of BA.2.12.1 can likely lead to increased transmission globally, but it has shown no difference in hospitalisation rates in comparison to BA.2.She urged governments across the world to closely monitor BA.2.12.1, BA.4, BA.5 and other sub-variants that could emerge in the future, emphasising the need to maintain Covid testing and sequencing. —IANS

Omicron subvariants BA.4 and BA.5 have been detected in more than a dozen countries driving Covid outbreaks across the world, according to the World Health Organization.

Omicron BA.4, BA.5 Sub-Variants Found In Over A Dozen Countries: WHO

Mumbai: For the first time in Maharashtra, four patients of B.A.4 sub-lineage and three cases of B.A.5 sub-lineage of the Omicron variant of coronavirus have been found, the state health department said on Saturday. These were mild sub-lineages and there was no cause for concern, a senior health official said.The sub-lineages of Omicron were found in April in some parts of the world including South Africa.Last week, cases were also reported in Tamil Nadu and Telangana in India. "The whole genome sequencing was conducted by the Institute of Science Education and Research, and its finding has been confirmed by the Indian Biological Data Centre in Faridabad. As many as seven patients, all from Pune, were detected with the infection of the sub-lineage of Omicron," a health department official said. "Four patients have the infection of B.A. 4 variant while others have contracted the B.A. 5. Four of them are men and three women. Four patients are above 50 years of age while two are in 20-40 age group while one patient is a nine-year-old child," he added."All the six adults have completed both the dosages of vaccine while one has taken the booster shot too. The child is unvaccinated. All of them had mild symptoms of COVID-19 and were treated successfully in home isolation," the official said.Their samples were taken between May 4 and 18. Two of them had travelled to South Africa and Belgium, while three had travelled to Kerala and Karnataka. The other two patients had no recent travel history, he said.Dr Pradeep Awate, epidemiologist and the State Surveillance Officer, Integrated Disease Surveillance Programme, said that B.A. 4 and B.A. 5 are sub-lineages of Omicron which itself is known for being mild.Hence, 'there is nothing to worry about its sub-lineages', he said."However, it is highly transmissible, which is one of the reasons behind the growing number of COVID-19 cases in the last couple of weeks. The cases are steadily going up everywhere, but patients are not being hospitalised in large numbers," Awate added."There is no severity found in the infection of these Omicron sub-lineages. But state officials are closely watching the situation," he said.On May 22, a B.A.4. case was found in Tamil Nadu while a B.A.5 infection was reported in Telangana.—PTI

For the first time in Maharashtra, four patients of B.A.4 sub-lineage and three cases of B.A.5 sub-lineage of the Omicron variant of coronavirus have been found, the state health department said on Saturday.

First cases of B.A. sub-lineage of Omicron found in Maharashtra

New Delhi: Children who previously had COVID-19 or the inflammatory condition MIS-C are not protected against the Omicron variant of coronavirus, according to a study which found vaccination, however, does afford protection. The findings of the study, published recently in the journal Nature Communications, are similar to those found in adults."I hear parents say, 'Oh, my kid had COVID last year'," said Adrienne Randolph, of Boston Children's Hospital, US, senior author of the research paper. "But we found that antibodies produced by prior infections in children don't neutralise Omicron, meaning that unvaccinated children remain susceptible to Omicron," Randolph said. The researchers, including Surender Khurana, from the US Food and Drug Administration obtained blood samples from 62 children and adolescents hospitalised with severe COVID-19.They also used data from 65 children and adolescents hospitalised with MIS-C, and 50 outpatients who had recovered from mild COVID-19.All the samples were taken during 2020 and early 2021, before the emergence of the Omicron variant.In the laboratory, the researchers exposed the samples to a pseudovirus, and measured how well antibodies in the samples were able to neutralise five different SARS-CoV-2 variants of concern: Alpha, Beta, Gamma, Delta, and Omicron.A pseudovirus is derived from SARS-CoV-2, but stripped of its virulence.Overall, children and adolescents showed some loss of antibody cross-neutralisation against all five variants, but the loss was most pronounced for Omicron, the researchers said."Omicron is very different from previous variants, with many mutations on the spike protein, and this work confirms that it is able to evade the antibody response," said Randolph. "Unvaccinated children remain susceptible," the researcher said.In contrast, children who had received two doses of COVID-19 vaccine showed higher neutralising antibody titers against the five variants, including Omicron.The researchers hope these findings will encourage parents to have their children and teens vaccinated.—PTI

Children who previously had COVID-19 or the inflammatory condition MIS-C are not protected against the Omicron variant of coronavirus, according to a study which found vaccination, however, does afford protection.

Previous infection doesn't protect kids from Omicron: Study

New Delhi: As India has been witnessing the subvariants of Omicron, Dr Tarun Kumar Sahni, Internal medicine and hyperbaric Oxygen therapist at Indraprastha Apollo hospital on Tuesday clarified that the BA.4 and BA.5 sublineages are quite "mild" because they are behaving like other mutants of COVID-19."The sub-variants BA.4 and BA.5 are behaving the same as other mutants of COVID-19 variants. We have observed that it is quite mild. A few months ago, WHO said that BA.4 and BA.5 are variants of concern. The European countries have also recently called it a variant of concern," Dr Kumar told ANI. He further said the variant of concern means a particular mutant that can quickly convert and become more serious and progressive than the other variants.The health expert also stressed following the COVID-19 protocols including wearing masks. He said " We all know these viruses will undergo mutation, that's why we are still telling people to wear masks so that the replication factor can be kept very low. The more it replicates, the more mutations will happen and more the possibility that one of the mutants can become more serious."After Tamil Nadu, Telangana, Hyderabad and Maharashtra have also detected the BA.4 and BA.5 cases. BA.4 and BA.5 are subvariants of the Omicron variant circulating globally. These were reported first from South Africa earlier this year and are now reported from several other countries. These variants have not been associated with disease severity or increased hospitalization.—ANI

As India has been witnessing the subvariants of Omicron, Dr Tarun Kumar Sahni, Internal medicine and hyperbaric Oxygen therapist at Indraprastha Apollo hospital on Tuesday clarified that the BA.4 and BA.5 sublineages are quite "mild" because they are behaving like other mutants of COVID-19.

BA.4, BA.5 are quite mild, behaving like other Omicron sub-variants

New York: The new Covid shot that specifically targets Omicron variant elicits a strong immune response against the strain, widely known to evade vaccines, Pfizer and BioNTech have said.According to the companies, just a month after administration, a booster dose of the Omicron-adapted monovalent candidates (at 30 and 60 microgram doses) increased neutralising antibodies against Omicron BA.1 to 13.5 and 19.6-fold above pre-booster dose levels.A booster dose of the Omicron-adapted bivalent candidates conferred a 9.1 and 10.9-fold increase in neutralising antibodies against Omicron BA.1, that was circulating last winter.Data from the Phase 2/3 trial that included 1,234 people aged 56 or older, showed that both Omicron-adapted vaccine candidates were well-tolerated in participants, the companies said."Based on these data, we believe we have two very strong Omicron-adapted candidates that elicit a substantially higher immune response against Omicron than we've seen to date," said Albert Bourla, Chairman and Chief Executive Officer, Pfizer, in a statement."Omicron has newly evolving sublineages that have outcompeted BA.1 and exhibit a trend of increasing potential for immune escape. We will therefore remain vigilant and are prepared to rapidly adapt our Omicron-adapted vaccine candidates to emerging sublineages if epidemiological and laboratory data suggest, added Prof. Ugur Sahin, CEO and Co-founder of BioNTech. Further, the companies noted that their early laboratory studies suggest that both Omicron-modified candidates also neutralise the Omicron BA.4 and BA.5 sub-variants that have been circulating more recently, with approximately 3-fold lower antibodies than BA.1. The companies stated they are continuing to collect data on how well the boosters perform versus the more recently circulating strains.The companies will share the results with the US Food and Drug Administration (FDA) and European Medicines Agency (EMA), ahead of the FDA advisory committee meeting on June 28, to discuss whether to update Covid vaccines.The companies have also submitted additional data from their ongoing Covid-19 booster studies, including data on an additional dose of their current Covid-19 vaccine and Beta candidate, to further demonstrate the flexibility and potential benefit of mRNA-based vaccines. Meanwhile, rival Moderna has also made a redesigned vaccine targeting the BA.1 Omicron subvariant. The company said its updated vaccine worked well against more recent Omicron subvariants, and that it was moving forward with plans to ask regulators for approval. —IANS

The new Covid shot that specifically targets Omicron variant elicits a strong immune response against the strain, widely known to evade vaccines, Pfizer and BioNTech have said.

Omicron-Targeting Covid Vax Shows High Immune Response: Pfizer & BioNTech

London: Eight out of 10 antibody therapy available for treatment of Covid-19 patients do not inhibit the new and emerging sub-variants of Omicron such as BA.2.12.1, BA.4, and BA.5, according to a study published in The Lancet Infectious Diseases.A team of researchers, including those from the German Primate Center (DPZ)-Leibniz Institute for Primate Research in Germany, studied 10 therapeutic antibodies - Sotrovimab by GlaxoSmithKline; Tixagevimab and Cilgavimab (packaged in Evusheld) by AstraZeneca; Bebtelovimab and cocktail Bamlanivimab and Etesevimab by Eli Lilly; Casirivimab-Imdevimab by Regeneron; Regdanvimab by Celltrion, and S2H97.The findings showed that only two were able to at least partially inhibit BA.2.12.1, BA.4, and BA.5 and that only one antibody, Bebtelovimab, efficiently blocked infection by all Omicron sub-variants.Furthermore, the study shows that the BA.2.12.1 and especially BA.4 and BA.5 are inhibited worse than their predecessors BA.1 and BA.2 by antibodies generated after vaccination or inoculation followed by infection.It is because the BA.2.12.1, BA.4, and BA.5 are immune escape variants. A pass-through infection with "old" Omicron sub-variants confers only limited protection against infection with "new" sub-variants, the researchers explained."These results confirm a trend that we have already seen in previous studies: Omicron sub-variants are not appreciably inhibited by most therapeutic antibodies and the few antibodies that inhibit frequently do so in a subvariant-specific fashion. Therefore, it is important to develop new antibodies in order to be prepared for future sub-variants," said Prerna Arora, first author from the German Primate Center. Antibodies from unvaccinated individuals that were infected with BA.1 or BA.2 in spring 2022 neutralised BA.2.12.1 with similar efficiency but were much less potent against BA.4 and BA.5. Therefore, it is likely that a previous BA.1 or BA.2 infection provides little protection against a subsequent infection with BA.4 or BA.5.Antibodies induced by three immunisations with the mRNA vaccine of BioNTech/Pfizer blocked all Omicron sub-variants. However, inhibition was less efficient as compared to that measured for a virus that circulated early during the pandemic, and inhibition of BA.2.12.1, BA.4, and BA.5 was less efficient as compared to BA.1 and BA.2.A Similar results were obtained for antibodies induced upon vaccination plus breakthrough infection. Although this so-called hybrid immunity conferred overall higher neutralising activity against all variants tested, inhibition of BA.2.12.1, BA.4 and BA.5 was significantly reduced. —IANS

Eight out of 10 antibody therapy available for treatment of Covid-19 patients do not inhibit the new and emerging sub-variants of Omicron such as BA.2.12.1, BA.4, and BA.5, according to a study published in The Lancet Infectious Diseases.

Antibody Therapy Less Effective Against New Omicron Strains: Lancet

New York: The latest Omicron sub-variants -- including the BA.4 and BA.5 forms causing new global surges in infections -- are even better at eluding vaccines and most antibody treatments than previous variants, finds a study.Subvariants BA.2.12.1, BA.4, and BA.5 are rapidly expanding worldwide, with BA.4/5 now making up more than 50 per cent of new Covid cases in the US. These sub-variants are thought to be even more transmissible than prior Omicron sub-variants, owing to several new mutations in spike proteins."The virus is continuing to evolve, as expected, and it is not surprising that these new, more transmissible sub-variants are becoming more dominant around the world," said David D. Ho, director of the Aaron Diamond AIDS Research Center at Columbia University. "Understanding how currently available vaccines and antibody treatments stand up to the new sub-variants is critical to developing strategies to prevent severe disease, hospitalisations, and deaths -- if not infection," Ho added.In laboratory experiments, Ho and his team studied the ability of antibodies from individuals who received at least three doses of an mRNA vaccine, or got two shots and were then infected with Omicron, to neutralise the new sub-variants.The study, published in Nature, revealed that while BA.2.12.1 is only modestly more resistant than BA.2 in individuals who were vaccinated and boosted, BA.4/5 was at least four times more resistant than its predecessor. In addition, the scientists tested the ability of 19 monoclonal antibody treatments to neutralise the variants and found that only one of the available antibody treatments remained highly effective against both BA.2.12.1 and BA.4/5."Our study suggests that as these highly transmissible sub-variants continue to expand around the globe, they will lead to more breakthrough infections in people who are vaccinated and boosted with currently available mRNA vaccines," Ho said. Though the current study suggests that the new variants may cause more infections in vaccinated individuals, the vaccines continue to provide good protection against severe disease."Efforts to develop new vaccine boosters aimed at BA.4/5 may improve protection against infection and severe disease," Ho said. —IANS

The latest Omicron sub-variants -- including the BA.4 and BA.5 forms causing new global surges in infections -- are even better at eluding vaccines and most antibody treatments than previous variants, finds a study.

New Omicron Sub-Variants Better At Evading Vax, Antibody Treatments

New Delhi: The Centre on Wednesday reduced the gap for administration of Covid vaccine booster doses from existing 9 months or 39 weeks to 6 months or 26 weeks.The Union Health Ministry said that as per the recommendation, it has been decided all beneficiaries from 18-59 years will be administered the booster after completion of 6 months or 26 weeks from the date of administration of 2nd dose. "In view of the evolving scientific evidence and global practices, the Standing Technical Sub Committee (STSCI) of the National Technical Advisory Group on Immunisation (NTAGI) has recommended to revise the duration between 2nd dose and precaution dose from existing 9 months or 39 weeks to 6 months or 26 weeks," it said, adding that the NTAGI has endorsed it. "Therefore it has now been decided that the precaution dose for all beneficiaries from 18-59 years will be administered after completion of 6 months or 26 weeks from the date of administration of 2nd dose at Private Covid Vaccination Centres (CVCs)," the ministry said in a letter to the states. It also said that for beneficiaries aged above 60 years and above as well as the Health Care Workers (HCWs) and Front Line Workers (FLWs), the precaution dose would be administered after completion of 6 months or 26 weeks from the date of administration of 2nd dose at Government CVCs free of charge. "Instructions in this regard may be issued to all the concerned officials and it may also be publicised widely. I look forward to your support and leadership for extending the benefits of precaution dose to all due beneficiaries at Covid Vaccination Centres (CVCs) as well as at household level during the ongoing Har Ghar Dastak 2.0 Campaign," Union Health Secretary Rajesh Bhushan said in the letter. —IANS

The Centre on Wednesday reduced the gap for administration of Covid vaccine booster doses from existing 9 months or 39 weeks to 6 months or 26 weeks.

Covid-19 Booster Dose Gap Reduced To 6 Months For All Adults

Tehran : Iranian President Ebrahim Raisi has said that passengers can only gain entry to Iran upon submission of negative Covid-19 test results and full compliance with Iranian health protocols, citing the recent increase in infections. In his address to a meeting of the national anti-coronavirus task force on Saturday, Raisi called for stricter compliance with the health regulations and instructions at all land, air and sea entries to Iran, Xinhua news agency reported, citing the Iranian presidency's website.He highlighted the necessity of receiving a booster dose of Covid-19 vaccines, noting those with underlying medical conditions should particularly take precautions.Iran's daily cases on Monday surpassed 1,000 for the first time since April 27, according to the Iranian Health Ministry's website.Iranian experts warn that two fast-spreading sub-variants of Omicron will become the prevailing strains in the country in the coming weeks.&nbsp;--- IANS

Iranian President Ebrahim Raisi has said that passengers can only gain entry to Iran upon submission of negative Covid-19 test results and full compliance with Iranian health protocols, citing the recent increase in infections.

Iran tightens entry rules amid increasing Covid-19 cases

New Delhi: The incidence of reinfection from the Omicron variant of Covid-19 is more common than previously thought, according to a study in Iceland. Reinfection is defined as a positive PCR test for SARS-CoV-2a-60 or more days from a previous positive test. The study, published in JAMA Network Open, surprisingly showed that two or more doses of vaccine were associated with a slightly higher probability of reinfection compared with 1 dose or less.
However, the "finding should be interpreted with caution because of limitations of our study, which include the inability to adjust for the complex relationships among prior infection, vaccine eligibility, and underlying conditions," Elias Eythorsson, from Landspitali-The National University Hospital of Iceland wrote in the paper.
For the study, the team analysed 11,536 PCR-positive persons. Reinfection was observed among 1,327 persons (11.5 per cent) during the Omicron period. Of those who had received 1 dose or less of vaccine, 11.7 per cent (1,007 of 8,598 individuals) were reinfected, compared with 10.9 per cent (320 of 2,938 individuals) who had received 2 or more doses. New zoonotic infection found in China, know its symptoms and precautions While reinfections among older individuals were fewer, the rate was highest (475 of 3,136 individuals [15.1 per cent]) among those aged 18 to 29 years, the researchers said. The probability of reinfection also increased with time from the initial infection and was higher among persons who had received two or more doses compared to one dose of vaccine or less, they noted.
"Longer time from initial infection was associated with a higher probability of reinfection, although the difference was smaller than expected," Eythorsson said.
"Our results suggest that reinfection is more common than previously thought. Now the key question is whether infection with the Omicron variant will produce better protection against Omicron reinfection, compared with other variants," Eythorsson added.
Omicron, which was first identified by South African researchers in November last year, is known to evade immunity induced both by vaccine and prior infections, making reinfections more common.
The relative protection of prior infection against reinfection with Omicron is known to be 56 per cent compared with 92 per cent for the Delta variant. —IANS

The incidence of reinfection from the Omicron variant of Covid-19 is more common than previously thought, according to a study in Iceland. Reinfection is defined as a positive PCR test for SARS-CoV-2a-60 or more days from a previous positive test.

Reinfection With Omicron More Common Than Thought: Study

Moscow: Russia's Gamaleya National Research Center of Epidemiology and Microbiology (Gamaleya Center) and the Russian Direct Investment Fund announced the development of the Sputnik V vaccine specifically adapted against Delta and Omicron variants of coronavirus.
Over the course of the pandemic, the Gamaleya Center has been consistently studying the new emerging variants of SARS-CoV-2 and adapting Sputnik V to them accordingly. The new version of Sputnik V has been Delta- and Omicron-adapted as Omicron is currently the dominant variant around the globe. This new version is also addressing the L-452-R mutation in Omicron BA5 variant which was not present in the BA1 variant.
"The Delta and Omicron-adapted version of Sputnik V is the most promising version of the vaccine specifically adapted to new variants as compared to those tailored against the combination of the original strain and Omicron variant. The Sputnik V vaccine adapted against the Delta and Omicron variants provides for a significant reduction in the viral load in the lungs of animals infected with the Omicron BA5 variant," the Russian medical research institute said in a statement.
The existing version of Sputnik V shows excellent results in preventing hospitalization and death caused by Omicron. A study conducted by a team of Russian scientists including representatives of the City Clinical Hospital No. 67 named after L.A.
Vorokhobov and the Gamaleya Center has demonstrated Sputnik V's efficacy against hospitalisation caused by Omicron for those vaccinated with 3 or 4 components (re-vaccination with Sputnik Light or Sputnik V after Sputnik V) was 97 per cent and 99.4 per cent against critical cases. These results have been published in June 2022 in the Vaccines leading peer-reviewed medical journal.
Sputnik V has become the most exported pharmaceutical product in Russian history being one of the safest and most effective vaccines against coronavirus in the world.
The Russian Direct Investment Fund invested in the development and production of both Sputnik V and Sputnik Light, which have helped save millions of lives globally. Sputnik V has been authorized in 71 countries with total population of over 4 billion people. Sputnik Light has been approved in more than 30 countries.
Sputnik V and Sputnik Light are based on a safe human adenoviral vector platform proven in more than 30 years and are not associated with serious adverse events such as myocarditis or pericarditis.
The high safety and efficacy of Sputnik V and Sputnik Light have been confirmed by more than 50 clinical studies and data compiled during national vaccination programs in various parts of the world, including Europe, Asia, the Middle East and Latin America.
Research on the Sputnik V vaccine has been published in leading international peer-reviewed medical journals, including The Lancet, Nature, Vaccines, Cell Reports Medicine and others. —ANI

Russia's Gamaleya National Research Center of Epidemiology and Microbiology (Gamaleya Center) and the Russian Direct Investment Fund announced the development of the Sputnik V vaccine specifically adapted against Delta and Omicron variants of coronavirus.

Russia Develops Delta & Omicron-Adapted Sputnik V Vaccine

New York: The US Food and Drug Administration (FDA) is expected to approve new covid-19 booster shots for newer Omicron strains this week, making them accessible to people in the country before any human testing is finished, the media reported.
The vaccines have been modified to target the most recent Omicron variant, but the US FDA won't have finished testing them on humans, the Daily Mail reported citing The Wall Street Journal.
The report mentioned that the FDA is instead relying on information from other sources, such as mice study and data from previous immunisation.&nbsp;
"Real world evidence from the current mRNA Covid-19 vaccines, which have been administered to millions of individuals, show us that the vaccines are safe," FDA Commissioner Robert Califf said in a tweet last week.
The official also wrote that the FDA will rely on the totality of the available evidence in making a decision.
This includes, clinical trial data from other bivalent mRNA Covid-19 boosters, RWE from current Covid-19 vaccines administered to millions of people, and non-clinical data for the bivalent BA.4/5 vaccines.
Clinical trial data, which will be used for the clearance of the vaccines, is similar to what the approach the FDA uses regarding flu shots, which are updated annually to keep up with mutating strains, the report said.
But some vaccine experts are not fans of the approach and believe it would be better to wait, rather than going with "mouse data", it added.&nbsp;
—IANS

The US Food and Drug Administration (FDA) is expected to approve new covid-19 booster shots for newer Omicron strains this week, making them accessible to people in the country before any human testing is finished, the media reported.

 US likely to authorise updated Covid booster shots for newer Omicron variants

Washington: Researchers analyzed the structures of the receptor-binding domain (RBD) of the SARS-CoV-2 omicron variant and its receptor, angiotensin-converting enzyme 2 (ACE2), to gain insight into the variant's potential animal reservoir.
Published in the journal 'Proceedings of the National Academy of Sciences' (PNAS), the study revealed that several key mutations in the omicron RBD are uniquely adapted to mouse ACE2 but are incompatible with human ACE2.
The findings suggest that the SARS-CoV-2 omicron variant may have evolved in mice before adapting to humans, providing insight into the variant's potential evolutionary origins, according to the authors.
The sudden emergence and rapid spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant has raised questions about its animal reservoir. Here, we investigated receptor recognition of the omicron's receptor-binding domain (RBD), focusing on four of its mutations (Q493R, Q498R, N501Y, and Y505H) surrounding two mutational hotspots. These mutations have variable effects on the RBD's affinity for human angiotensin-converting enzyme 2 (ACE2), but they all enhance the RBD's affinity for mouse ACE2. We further determined the crystal structure of omicron RBD complexed with mouse ACE2. The structure showed that all four mutations are viral adaptations to mouse ACE2: three of them (Q493R, Q498R, and Y505H) are uniquely adapted to mouse ACE2, whereas the other one (N501Y) is adapted to both human ACE2 and mouse ACE2. These data reveal that the omicron RBD was well adapted to mouse ACE2 before omicron started to infect humans, providing insight into the potential evolutionary origin of the omicron variant.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant emerged abruptly and spread rapidly around the globe (1-4). Tracking the animal reservoir of SARS-CoV-2 and its variants is important for understanding the current COVID-19 pandemic and preventing future pandemics. Speculations about the source of the omicron variant are abundant, yet experimental evidence has been scarce (5). The interactions between the receptor-binding domain (RBD) of coronavirus spike proteins and their host receptor are among the best systems for understanding coronavirus evolution (6, 7). Both SARS-CoV-2 and closely related SARS-CoV-1 recognize human angiotensin-converting enzyme 2 (ACE2) as their receptor (8-10). Previous research on the receptor recognition of SARS-CoV-1 has provided insight into the animal origin of SARS-CoV-1 (11-15). The RBD of the original SARS-CoV-2 strain (i.e., prototypic RBD) differs from the RBD of a bat coronavirus by only a few residues, supporting a bat origin of the prototypic RBD (16). The omicron RBD (strain BA.2) differs from the prototypic RBD by 16 residues, seven of which are located in the receptor-binding motif (RBM) that directly contacts ACE2 (3). To recover the evolutionary traces left by these RBM mutations, this study compared the structural adaptations of the omicron RBD to ACE2 from human and mouse, two possible sources of omicron (5).
Three virus-binding hotspots have been identified at the interfaces between SARS-CoV-2 RBD and human ACE2 (hACE2) and between SARS-CoV-1 RBD and hACE2 (14, 17, 18). These hotspots center on Lys31 in hACE2 (i.e., hotspot-31), Lys353 in hACE2 (i.e., hotspot-353), and a receptor-binding ridge in the viral RBD (i.e., hotspot-ridge) (Fig. 1A). These virus-binding hotspots are also mutational hotspots for SARS-CoV-1: all of the RBM mutations occurred around the hotspots and impacted the structural stability of the hotspots (13, 14).
Establishment of the "hotspots" concept was instrumental in determining the molecular mechanisms by which SARS-CoV-1 was transmitted from palm civets to humans (11-15). The RBM mutations in the SARS-CoV-2 omicron variant are also around the hotspots (Fig. 1A). Curiously, only a few of these omicron mutations enhance the RBD's affinity for hACE2, while some other mutations reduce it (Fig. 1B) (17). Structural details of the interface between the omicron RBM (strain BA.1) and hACE2 elucidated the role of each of these mutations in binding hACE2 (17). The omicron mutations that reduce the RBD's affinity for hACE2 are structurally incompatible with hACE2, raising questions about what other species may have mediated the evolution of omicron.
In this study, we provide biochemical and structural evidence demonstrating that the omicron mutations are better adapted to mouse ACE2 (mACE2) than to hACE2, suggesting that mice mediated the onset of the omicron variant. Our study helps clarify the animal reservoir of the omicron variant and contributes to the understanding of SARS-CoV-2 evolution. The findings may facilitate epidemiological surveillance of SARS-CoV-2 in animals to prevent future coronavirus pandemics. —ANI

Researchers analyzed the structures of the receptor-binding domain (RBD) of the SARS-CoV-2 omicron variant and its receptor, angiotensin-converting enzyme 2 (ACE2), to gain insight into the variant's potential animal reservoir.

 Study Provides Insight Into Potential Animal Reservoir Of SARS-CoV-2 Omicron

New York: People who have received two or three doses of an mRNA Covid-19 vaccine are significantly more likely to have milder illnesses if infected with the Delta or Omicron coronavirus variants than those who are unvaccinated, according to a study.
The study, involving a team of University of Utah researchers, examined health care personnel, first responders and other frontline workers in the US.
It's encouraging that the mRNA vaccines hold up rather well against these variants," said Sarang Yoon, assistant professor in the Department of Family and Preventive Medicine at University of Utah Health.
"We know that breakthrough cases are more likely with Delta and Omicron than the initial strain, but the vaccines still do a good job of limiting the severity of the infection," Yoon said in a study published in the Journal of the American Medical Association (JAMA).
Researchers examined 1,199 participants who developed Covid-19 infections.
Of the participants, 24 per cent were infected with Delta and 62 per cent contracted Omicron, while 14 per cent had the original virus strain.
In the case of Delta, participants who had received two vaccine doses were significantly less likely to be symptomatic than those who were unvaccinated.
In the case of Omicron, the risk of symptomatic infection was similar between participants with two vaccine doses and those who were unvaccinated, while those with three doses experienced a higher risk than the unvaccinated.
The authors noted that, while the study is among the largest of its kind examining Covid-19 vaccines over time and across variants, grouping participants by variant and vaccine status resulted in some combinations with relatively few people, affecting the precision of the findings.
There were also results the authors characterised as "unexpected" among participants who received three doses and had symptomatic Omicron infections. —IANS

People who have received two or three doses of an mRNA Covid-19 vaccine are significantly more likely to have milder illnesses if infected with the Delta or Omicron coronavirus variants than those who are unvaccinated, according to a study.

mRNA Vaccines Significantly Cut Severity Of Delta, Omicron Infections

New York: An international team of researchers has identified a pan-variant and ultra-potent neutralising antibody that can offset Omicron variants.
Named 'S2X324', its neutralising potency was largely unaffected by any of the Omicron variants tested, said the study published in the journal Science.
The scientists suggested that combining this antibody with others in a cocktail might reduce the chances of the virus becoming antibody-treatment resistant.
The team looked at several aspects of the effects of exposure to earlier forms of the SARS-CoV-2 spike antigen -- or immune-provoking protein -- on the immune system's reaction to the Omicron variants.
Past studies from the same team have noted that the BA.1 Omicron variant emerged as a "major antigenic shift due to the unprecedented magnitude of immune evasion associated with this variant of concern".
They explained that mutations in two of the main antibody targets in the virus explain why there is markedly reduced antibody neutralising ability against these variants, especially in people who have not received booster doses. "As a result, an increasing number of reinfections are occurring," the researchers wrote, "even though these cases tend to be milder than in infections of immunologically naA-ve individuals".
The recent scientific studies in this area have been led by the labs of David Veesler, associate professor of biochemistry at the University of Washington in Seattle and Howard Hughes Medical Institute Investigator, and Davide Corti of Humabs BioMed SA of Vir Biotechnology in Switzerland. The Omicron variants appeared at the end of 2021 and have marked genetic differences from the ancestral SARS-CoV-2. The many, distinct mutations in their infection machinery have enabled them to escape from antibodies elicited from the original series of vaccines, from a history of infection, or from both of those two immune-system training events.
People who had a breakthrough infection after vaccination also produced neutralising antibodies against these variants in the mucus lining the inside of their noses.
However, people who only received the vaccine did not generate antibodies in their nasal mucosa. "This finding lends support to efforts to develop and evaluate next-generation Covid vaccines that could be delivered intranasally as the nose is generally the site where the virus first enters the body," said the scientists.
The lead authors on the paper are from the Veesler lab, the Corti lab, and Washington University in St. Louis. —IANS

An international team of researchers has identified a pan-variant and ultra-potent neutralising antibody that can offset Omicron variants.

Scientists Identify Ultra-Potent Antibody That Can Offset All Omicron Variants

New Delhi: Omicron sub-lineage BQ.1.1, currently on the rise worldwide, is resistant to all approved antibody therapies, a new Lancet study led by an Indian-origin researcher has revealed.
The researchers found that the Omicron subvariant BQ.1.1 could not be neutralised by either individual antibodies or antibody cocktails.
"In total, we tested 12 individual antibodies, six of which are approved for clinical use in Europe, and four antibody cocktails," said Prerna Arora, lead author of the study published in The Lancet Infectious Diseases.
The team of researchers from the Infection Biology Unit at the German Primate Center, Leibniz Institute for Primate Research and the Division of Molecular Immunology at the Friedrich-Alexander-University Erlangen-Nurnberg investigated how efficiently approved antibody therapies inhibit the currently circulating Omicron subvariants.
"With high-risk patients in mind, we are very concerned about the Omicron subvariant BQ.1.1 being resistant to all approved antibody therapies," said study leader Markus Hoffman.
Particularly in regions where BQ.1.1 is widespread, physicians should not rely on antibody therapies alone when treating infected high-risk patients, "But should also consider administering other drugs such as paxlovid or molnupiravir," Hoffmann added.
In contrast, the currently predominant Omicron subvariant BA.5 was still neutralised by one approved antibody and two approved antibody cocktails.
The finding that the Omicron subvariant BQ.1.1 is already resistant to a new antibody therapy that is about to be approved in the US highlights the importance of developing new antibody therapies against Covid-19. "The ever-increasing development of antibody resistance of SARS-CoV-2 variants calls for the development of new antibody therapies that are specifically targeted to currently circulating and future viral variants. Ideally, they should target regions in the spike protein that have little potential for escape mutations," noted Stefan Pohlmann, head of the Infection Biology Unit at the German Primate Center, Leibniz Institute for Primate Research. —IANS

Omicron sub-lineage BQ.1.1, currently on the rise worldwide, is resistant to all approved antibody therapies, a new Lancet study led by an Indian-origin researcher has revealed.

New Omicron Subvariant Resistant To All Antibody Therapies: Indian-Origin Scientist

New Delhi: With this year's Omicron-led Covid wave, the death rate was much lower in comparison with that of the Delta variant last year. This lowered severity and threat level could be one of the main reasons for the lower spread of the booster dose across India, according to Dr Rajeev Jayadevan, Co-Chairman, National IMA COVID Task Force.
Jayadevan was explaining to IANS the reasons for the low acceptance of the third vaccine (or booster) dose.
The government administered booster doses against Covid-19 free of cost to all adults for 75 days from July 15 to mark the 75th year of Independence.
According to official data, the 75-day free drive significantly increased the demand for the third shot of the vaccine and brought the coverage of the eligible population up from 8 per cent to 27 per cent. In all, 159.2 million precaution doses were administered in these 75 days. The rate of the overall booster dose intake, however, was low among the general population.
"Most adults in India are fully vaccinated, and many have also had natural infection. There is substantial immunity prevailing in the community, which is the likely reason for low hospital caseloads of Covid in most parts of India at this time. Booster doses revive immune memory and also boost mucosal immunity for a few months. But the vaccines used in India are different from those used in the west. Besides, they are based on the ancestral strain, which is no longer in circulation. We also do not have published studies on clinical outcomes in our population after booster use," said Dr Jayavedan.
About the booster outside the country, he said: "Booster studies from western nations are primarily based on mRNA vaccines, which are not used in India. Therefore western research conclusions cannot be extrapolated to the India scenario. Besides, the boosters used in western nations now are based on Omicron, which is a more recent version of the virus. Although the lab based data are encouraging, whether such bivalent boosters are better than the original when used in actual people, remains to be seen." Being a cyclical viral disease, Covid-19 occurs in waves spread months apart, and each geographic region goes through a high tide and low tide. Those who took a booster dose should not be under the impression that all other precautions can be discarded. Indoor masking in public places and attention to ventilation and air quality are important to reduce overall infection risk. "We are somewhat fortunate that the latest variant Omicron and its numerous sublineages such as BA.2.75 and XBB are of lower severity than delta, although more infective and immune evasive. Importantly, Omicron sublineages cause less lung damage than Delta. Continued evolution is occurring in this new virus which is still not fully known to man. Active surveillance is required to detect and report any further new variants that could have a different biological property than Omicron. We must also keep in mind that for a new variant to cover the globe it takes very little time, for example Omicron took only 6 weeks to spread all around the world, knocking Delta off its pedestal. We cannot therefore let our guard down," he said. "Mucosal vaccines are relatively new. They have the ability to shore up the immunity in the nose and throat, which are the entry points of the virus - and this could reduce infection and transmission risk. They also have a role as boosters. However, large scale studies are awaited about how effective and safe they are. Those most likely to benefit from booster use are older individuals, and those who have certain disease conditions that put them at greater risk for serious Covid outcomes," Dr Jayadevan advised. —IANS

With this year's Omicron-led Covid wave, the death rate was much lower in comparison with that of the Delta variant last year. This lowered severity and threat level could be one of the main reasons for the lower spread of the booster dose across India, according to Dr Rajeev Jayadevan, Co-Chairman, National IMA COVID Task Force.

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