PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

New study from Japan shows SARS-CoV-2 Omicron XBB.1.5 variant is highly transmissible and infectious

Team led by Japanese researchers characterizes the SARS-CoV-2 Omicron XBB.1.5 variant and assesses its danger to global public health

New study from Japan shows SARS-CoV-2 Omicron XBB.1.5 variant is highly transmissible and infectious
2023-03-15
(Press-News.org) COVID-19 has caused significant global panic after its rapid emergence more than 3 years ago. Although we now have highly effective vaccines against the SARS-CoV-2 virus, which causes COVID-19, scientists continue to study emerging SARS-CoV-2 variants in order to safeguard public health and devise global preventive strategies against emerging variants. A team led by Japanese researchers has recently discovered that the SARS-CoV-2 Omicron XBB.1.5 variant, prevalent in the Western hemisphere, has high transmissibility and infectivity.  

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been responsible for millions of deaths worldwide. Although scientists have designed novel vaccines to counter COVID-19, they are constantly on the lookout for emerging variants that can bypass vaccine resistance and potentially jeopardize global public health. A team led by Japanese researchers has recently been successful in characterizing the new SARS-CoV-2 Omicron XBB.1.5 variant, which was first detected in October 2022. Their findings were published on January 31, 2023 in volume 23 of The Lancet Infectious Diseases.

Says senior author Prof. Kei Sato from the Division of Systems Virology, The Institute of Medical Science, The University of Tokyo, Japan, “Because the Omicron XBB.1.5 variant can spread more rapidly than previous variants and has a potential to cause the next epidemic surge, we should carefully monitor it to safeguard public health.”      

While studying emerging variants of the SARs-CoV-2 Omicron lineage, the research team made a startling discovery: the SARS-CoV-2 Omicron XBB.1.5 variant has a novel mutation in the spike (S) protein—the protein that anchors the virus firmly to the human angiotensin converting enzyme-2 (ACE2) receptor, thus facilitating the invasion of human cells. The serine-to-proline amino acid mutation noted at residue no. 486 in the S protein is virologically concerning because of a variety of reasons. 

Sharing his concerns, first author Keiya Uriu from the Division of Systems Virology, Department of Microbiology and Immunology, The University of Tokyo, Japan, says, “In late 2022, the SARS-CoV-2 Omicron BQ.1 and XBB lineages, characterized by amino acid substitutions in the S protein and increased viral fitness, had become predominant in the Western and Eastern Hemisphere, respectively. In 2022, we elucidated the characteristics of a variety of newly emerging SARS-CoV-2 Omicron subvariants. At the end of 2022, the XBB.1.5 variant, a descendant of XBB.1 that acquired the S:S486P substitution, emerged and was rapidly spreading in the USA.”

To gain mechanistic insights into the infectivity, transmissibility, and immune response associated with XBB.1.5, the team conducted a series of experiments. For instance, upon conducting epidemic dynamics analysis—statistical modeling that facilitates the analysis of the general characteristics of any epidemic—the team realized that the relative effective reproduction number (Re) of XBB.1.5 was 1.2-fold greater than that of the parental XBB.1. This indicated that an individual with the XBB.1.5 variant could infect 1.2 times more people in the population than someone with the parental XBB.1 variant. Moreover, the team also realized that, as of December 2022, XBB.1.5 was rapidly outcompeting BQ.1.1, the predominant lineage in the United States. 

Co-first-author Jumpei Ito from the Division of Systems Virology, remarks, “Our data suggest that XBB.1.5 will rapidly spread worldwide in the near future.”

The team also studied the virological features of XBB.1.5 to determine how tightly the S protein of the new variant interacts with the human ACE2 receptor. To this end, the researchers conducted a yeast surface display assay. The results showed that the dissociation constant (KD) corresponding to the physical interaction between the XBB.1.5 S receptor-binding domain (RBD) and the human ACE2 receptor is significantly (4.3-fold) lower than that for XBB.1 S RBD. “In other words, the XBB.1.5 variant binds to human ACE2 receptor with very high affinity,” explains Shigeru Fujita from the Division of Systems Virology.

Further experiments using lentivirus-based pseudoviruses also showed that XBB.1.5 had approximately 3-fold higher infectivity than XBB.1. These results suggest that XBB.1.5 exhibits a remarkably strong affinity to the human ACE2 receptor, which can be attributed to the S486P substitution.

The study by Prof. Sato and his team led to another important discovery from an immunization perspective. The XBB.1.5 S protein was found to be highly resistant to neutralization antibodies elicited by breakthrough infection with the BA.2/BA.5 subvariants. In other words, patients with prior infection from the BA.2/BA.5 subvariants may not show robust immunity against XBB.1.5, increasing their chances of infection and disease. 

“The results of our virological experiments explain why the Omicron XBB.1.5 variant has a higher transmissibility than past variants: This variant acquired strong binding ability to human ACE2 while maintaining a higher ability to escape from neutralizing antibodies,” says Yusuke Kosugi from the Division of Systems Virology, Department of Microbiology and Immunology.

Contributing members of The Genotype to Phenotype Japan (G2P-Japan) Consortium conclude, “The SARS-CoV-2 Omicron XBB.1.5 variant does show enhanced transmissibility. Although few cases have been detected in the Eastern hemisphere, it could become a looming threat. Imminent prevention measures are needed.”

Thanks to the research team for the early warning! Meanwhile, we must continue adopting safe practices to defend ourselves from XBB.1.5. 
 

END

[Attachments] See images for this press release:
New study from Japan shows SARS-CoV-2 Omicron XBB.1.5 variant is highly transmissible and infectious

ELSE PRESS RELEASES FROM THIS DATE:

Immune cell gives possible explanation for sex differences in pancreatic cancer

2023-03-15
Immunotherapy is an effective form of therapy for different types of cancer. However, for pancreatic cancer, its effect is limited and differs between men and women. Researchers at Karolinska Institutet have now found a possible explanation for this sex difference. The study, which is published in Cancer Research, reveals the presence of an immune cell in women with pancreatic cancer that obstructs the body’s immune response. The results can pave the way for a more sex-specific treatment. “More and more evidence is coming in that male and female hormones affect ...

Tax policy may not be enough to combat climate change

2023-03-15
A new paper in The Review of Economic Studies, published by Oxford University Press, indicates that carbon taxes will be less effective at reducing carbon emissions than previously thought. It also finds that tax interventions needed to achieve goals agreed upon in the Paris Climate Agreement of 2016 will need to be larger than previously thought. There is growing interest among researchers and policymakers in using economic policy to reduce or eliminate carbon dioxide emissions. Policy can reduce carbon emissions in several ways, including pushing the economy towards cleaner sources of energy and decreasing overall energy use. The researchers ...

Rapid surge in highly contagious killer fungus poses new threat to amphibians across Africa

2023-03-15
Mass fungus infections that drive populations worldwide to near-collapse don’t just occur in science fiction. Chytridiomycosis, the worst vertebrate disease in recorded history, has already wiped out hundreds of species of amphibians around the world. Due to a large part to this fungal disease, 41% of amphibians are currently threatened with extinction. Only species living in Africa seemed to have been relatively spared from the scourge of chytridiomycosis – at least so far. Now, a study in Frontiers in Conservation Science ...

Discovering the unexplored: Synthesis and analysis of a new orthorhombic Sn3O4 polymorph

Discovering the unexplored: Synthesis and analysis of a new orthorhombic Sn3O4 polymorph
2023-03-15
Oxides of tin (SnxOy) are found in many of modern technologies due to their versatile nature. The multivalent oxidation states of tin—Sn2+ and Sn4+—impart tin oxides with electroconductivity, photocatalysis, and various functional properties. For the photocatalysis application of tin oxides, a narrow bandgap for visible-light absorption is indispensable to utilize a wide range of solar energy. Hence, the discovery of new SnxOy could help improve the efficiency of many environmentally significant photocatalytic reactions like water splitting and CO2 reduction. ...

CHEST releases clinical practice guideline on respiratory management of patients with neuromuscular weakness

2023-03-15
Glenview, Illinois – The American College of Chest Physicians® (CHEST) recently released a new clinical guideline on respiratory management of patients with neuromuscular weakness. Published in the journal CHEST®, the guideline contains 15 evidence-based recommendations, a good practice statement and an ungraded consensus-based statement. Endorsed by the American Association for Respiratory Care, the American Thoracic Society, the American Academy of Sleep Medicine and the Canadian Thoracic Society, the guideline recommendations include mouthpiece ventilation, transition to home mechanical ventilation, salivary secretion management and airway clearance ...

Researcher solves nearly 60-year-old game theory dilemma

2023-03-15
To understand how driverless vehicles can navigate the complexities of the road, researchers often use game theory — mathematical models representing the way rational agents behave strategically to meet their goals.  Dejan Milutinovic, professor of electrical and computer engineering at UC Santa Cruz, has long worked with colleagues on the complex subset of game theory called differential games, which have to do with game players in motion. One of these games is called the wall pursuit game, a relatively simple model for a situation in which a faster pursuer ...

Mediterranean diet cuts women’s cardiovascular disease and death risk by nearly 25%

2023-03-15
Sticking closely to a Mediterranean diet cuts a woman’s risks of cardiovascular disease and death by nearly 25%, finds a pooled data analysis of the available evidence—the first of its kind—published online in the journal Heart. The findings prompt the researchers to call for more sex specific research to guide clinical practice in heart health. Cardiovascular disease accounts for more than a third of all deaths in women around the world. While a healthy diet is a key plank of prevention, most relevant clinical trials have included relatively few women or haven’t reported the results by sex, say the researchers. And current guidelines ...

High blood caffeine level might curb amount of body fat and type 2 diabetes risk

2023-03-15
A high blood caffeine level might curb the amount of body fat a person carries and their risk of type 2 diabetes, suggests research published in the open access journal BMJ Medicine. In light of their findings, the potential role of calorie free caffeinated drinks for lowering the risks of obesity and type 2 diabetes is probably now worth exploring, say the researchers. Previously published research indicates that drinking 3-5 daily cups of coffee, a rich source of caffeine, is associated with a lower risk ...

TikTok health information videos on Mpox often inaccurate and of poor quality

2023-03-15
Health information on M(onkey)pox, posted on the social media platform TikTok, is often inaccurate, incomplete, and of poor quality, finds a recent analysis of relevant videos, published in the open access journal BMJ Global Health. The findings highlight the potential risks of using social media for health information, particularly during public health emergencies, warn the researchers. Mpox, formerly called monkeypox, usually describes fever, swollen lymph glands (lymphadenopathy), and painful skin pustules all over the body ...

Altered “neuronal avalanches” in brains of epilepsy patients tied to cognitive performance

2023-03-15
New research by the Human Brain Project has found that in the brains of patients with epilepsy, changes in large scale neuronal activations can be detected in the brain’s resting state activity, even when no seizure is ongoing. The non-invasive approach could lead to a new method to aid epilepsy diagnostics. Diagnosing epilepsy can be problematic for patients, who sometimes have to wear helmets and electrodes for prolonged periods of time waiting for an epileptic episode to happen, so that the clinicians can document it with EEG. Alternatively, the seizure is artificially induced, causing discomfort. The new ...

LAST 30 PRESS RELEASES:

Bioinformatics approach could help optimize soldiers’ training for improved readiness and recovery

Earth scientists describe a new kind of volcanic eruption

Warmer wetter climate predicted to bring societal and ecological impact to the Tibetan Plateau

Feeding infants peanut products protects against allergy into adolescence

Who will like beetle skewers? What Europeans think about alternative protein food

ETRI wins ‘iF Design Award’ for mobile collaborative robot

Combating carbon footprint: novel reactor system converts carbon dioxide into usable fuel

Investigating the origin of circatidal rhythms in freshwater snails

Altering cellular interactions around amyloid plaques may offer novel Alzheimer’s treatment strategies

Brain damage reveals part of the brain necessary for helping others

Surprising properties of elastic turbulence discovered

Study assesses cancer-related care at US hospitals predominantly serving minority populations compared with non-minority serving hospitals

First in-human investigator-initiated clinical trial to launch for refractory prostate cancer patients: Novel alpha therapy targets prostate-specific membrane antigen

Will generative AI change the way universities communicate?

Artificial Intelligence could help cure loneliness, says expert

Echidnapus identified from an ‘Age of Monotremes’

Semaglutide may protect kidney function in individuals with overweight or obesity and cardiovascular disease

New technique detects novel biomarkers for kidney diseases with nephrotic syndrome

Political elites take advantage of anti-partisan protests to disrupt politics

Tiny target discovered on RNA to short-circuit inflammation, UC Santa Cruz researchers find

Charge your laptop in a minute? Supercapacitors can help; new research offers clues

Scientists discover CO2 and CO ices in outskirts of solar system

Theory and experiment combine to shine a new light on proton spin

PKMYT1, a potential ‘Achilles heel’ of treatment resistant ER+ breast cancers with the poorest prognosis

PH-binding motifs as a platform for drug design: Lessons from protease-activated receptors (PARs)

Virginia Tech researcher creates new tool to move tiny bioparticles

On repeat: Biologists observe recurring evolutionary changes, over time, in stick insects

Understanding a broken heart

Genetic cause of rare childhood immune disorders discovered

With wobbling stars, astronomers gauge mass of 126 exoplanets and find 15 new ones

[Press-News.org] New study from Japan shows SARS-CoV-2 Omicron XBB.1.5 variant is highly transmissible and infectious
Team led by Japanese researchers characterizes the SARS-CoV-2 Omicron XBB.1.5 variant and assesses its danger to global public health