Since it was detected in August 2023, the JN.1 variant of COVID has spread widely. It has become dominant in Australia and around the world, driving the biggest COVID wave seen in many jurisdictions for at least the past year.
The World Health Organization (WHO) classified JN.1 as a “variant of interest” in December 2023 and in January strongly stated COVID was a continuing global health threat causing “far too much”
JN.1 is significant. First as a pathogen – it’s a surprisingly new-look version of SARS-CoV-2 (the virus that causes COVID) and is rapidly displacing other circulating strains (omicron XBB).
It’s also significant because of what it says about COVID’s evolution. Normally, SARS-CoV-2 variants look quite similar to what was there before, accumulating just a few mutations at a time that give the virus a meaningful advantage over its parent.
However, occasionally, as was the case when omicron (B.1.1.529) arose two years ago, variants emerge seemingly out of the blue that have markedly different characteristics to what was there before. This has significant implications for disease and transmission.
Until now, it wasn’t clear this “step-change” evolution would happen again, especially given the ongoing success of the steadily evolving omicron variants.
JN.1 is so distinct and causing such a wave of new infections that many are wondering whether the WHO will recognize JN.1 as the next variant of concern with its own Greek letter. In any case, with JN.1 we’ve entered a new phase of the pandemic.
Where did JN.1 come from?
The JN.1 (or BA.2.86.1.1) story begins with the emergence of its parent lineage BA.2.86 around mid-2023, which originated from a much earlier (2022) omicron sub-variant BA.2.
Chronic infections that may linger unresolved for months (if not years, in some people) likely play a role in the emergence of these step-change variants.
In chronically infected people, the virus silently tests and eventually retains many mutations that help it avoid immunity and survive in that person. For BA.2.86, this resulted in more than 30 mutations of the spike protein (a protein on the surface of SARS-CoV-2 that allows it to attach to our cells).
The sheer volume of infections occurring globally sets the scene for major viral evolution. SARS-CoV-2 continues to have a very high rate of mutation. Accordingly, JN.1 itself is already mutating and evolving quickly.
How is JN.1 different to other variants?
BA.2.86 and now JN.1 are behaving in a manner that looks unique in laboratory studies in two ways.
The first relates to how the virus evades immunity. JN.1 has inherited more than 30 mutations in its spike protein. It also acquired a new mutation, L455S, which further decreases the ability of antibodies (one part of the immune system’s protective response) to bind to the virus and prevent infection.
The second involves changes to the way JN.1 enters and replicates in our cells. Without delving into the molecular details, recent high-profile lab-based research from the United States and Europe observed BA.2.86 to enter cells from the lung in a similar way to pre-omicron variants like delta. However, in contrast, preliminary work by Australia’s Kirby Institute using different techniques finds replication characteristics that are aligned better with omicron lineages.
Further research to resolve these different cell entry findings is important because it has implications for where the virus may prefer to replicate in the body, which could affect disease severity and transmission.
Whatever the case, these findings show JN.1 (and SARS-CoV-2 in general) can not only navigate its way around our immune system, but is finding new ways to infect cells and transmit effectively. We need to further study how this plays out in people and how it affects clinical outcomes.
Is JN.1 more severe?
The step-change evolution of BA.2.86, combined with the immune-evading features in JN.1, has given the virus a global growth advantage well beyond the XBB.1-based lineages we faced in 2023.
Despite these features, evidence suggests our adaptive immune system could still recognize and respond to BA.286 and JN.1 effectively. Updated monovalent vaccines, tests, and treatments remain effective against JN.1.
There are two elements to “severity”: first if it is more “intrinsically” severe (worse illness with an infection in the absence of any immunity) and second if the virus has greater transmission, causing greater illness and deaths, simply because it infects more people. The latter is certainly the case with JN.1.
What next?
We simply don’t know if this virus is on an evolutionary track to becoming the “next common cold” or not, nor have any idea of what that timeframe might be. While examining the trajectories of four historic coronaviruses could give us a glimpse of where we may be heading, this should be considered as just one possible path. The emergence of JN.1 underlines that we are experiencing a continuing epidemic with COVID and that looks like the way forward for the foreseeable future.
We are now in a new pandemic phase: post-emergency. Yet COVID remains the major infectious disease causing harm globally, from both acute infections and long COVID. At a societal and an individual level we need to re-think the risks of accepting wave after wave of infection.
Altogether, this underscores the importance of comprehensive strategies to reduce COVID transmission and impacts, with the least imposition (such as clean indoor air interventions).
People are advised to continue to take active steps to protect themselves and those around them.
For better pandemic preparedness for emerging threats and an improved response to the current one it is crucial we continue global surveillance. The low representation of low- and middle-income countries is a concerning blind spot. Intensified research is also crucial.
Written by:
- Suman Majumdar – Associate Professor and Chief Health Officer – COVID and Health Emergencies, Burnet Institute
- Brendan Crabb – Director and CEO, Burnet Institute
- Emma Pakula – Senior Research and Policy Officer, Burnet Institute
- Stuart Turville – Associate Professor, Immunovirology and Pathogenesis Program, Kirby Institute, UNSW Sydney
Adapted from an article originally published in The Conversation.
News
According to Researchers, Your Breathing Patterns Could Hold the Key to Better Memory
Breathing synchronizes brain waves that support memory consolidation. A new study from Northwestern Medicine reports that, much like a conductor harmonizes various instruments in an orchestra to create a symphony, breathing synchronizes hippocampal brain waves to [...]
The Hidden Culprit Behind Alzheimer’s Revealed: Microglia Under the Microscope
Researchers at the CUNY Graduate Center have made a groundbreaking discovery in Alzheimer’s disease research, identifying a critical link between cellular stress in the brain and disease progression. Their study focuses on microglia, the brain’s immune [...]
“Mirror Bacteria” Warning: A New Kind of Life Could Pose a Global Threat
Mirror life, a concept involving synthetic organisms with reversed molecular structures, carries significant risks despite its potential for medical advancements. Experts warn that mirror bacteria could escape natural biological controls, potentially evolving to exploit [...]
Lingering Viral Fragments: The Hidden Cause of Long COVID
Long COVID, affecting 5-10% of COVID-19 patients, might be caused by the enduring presence of the virus in the body. Research suggests that viral fragments, possibly live, linger and lead to symptoms. Addressing this involves antiviral treatments, enhanced [...]
Hidden Scars: How COVID Lockdowns Altered Teen Brains Forever
Research from the University of Washington revealed that COVID-19 lockdowns led to accelerated cortical thinning in adolescents, impacting brain development significantly. This effect was more pronounced in females than males, raising concerns about long-term brain health. The study [...]
Simple Blood Test To Detect Dementia Before Symptoms Appear
UCLA researchers have identified placental growth factor (PlGF) as a potential blood biomarker for early detection of cognitive impairment and dementia. High PlGF levels correlate with increased vascular permeability, suggesting its role in the development [...]
Investing Goldman Sachs asks ‘Is curing patients a sustainable business model?’
Goldman Sachs analysts attempted to address a touchy subject for biotech companies, especially those involved in the pioneering “gene therapy” treatment: cures could be bad for business in the long run. “Is curing patients [...]
The risks of reversed chirality: Study highlights dangers of mirror organisms
A groundbreaking study evaluates the feasibility, risks, and ethical considerations of creating mirror bacteria with reversed chirality, highlighting potential threats to health and ecosystems. In a recent study published in Science, a team of researchers [...]
Alarming Mutation in H5N1 Virus Raises Pandemic Red Flags
NIH-funded study concludes that the risk of human infection remains low A recent study published in Science and funded by the National Institutes of Health (NIH) has found that a single alteration in a protein on the surface [...]
Scientists Discover Genetic Changes Linked to Autism, Schizophrenia
The Tbx1 gene influences brain volume and social behavior in autism and schizophrenia, with its deficiency linked to amygdala shrinkage and impaired social incentive evaluation. A study published in Molecular Psychiatry has linked changes in brain [...]
How much permafrost will melt this century, and where will its carbon go?
Among the many things global warming will be melting this century—sea ice, land glaciers and tourist businesses in seaside towns across the world—is permafrost. Lying underneath 15% of the northern hemisphere, permafrost consists of [...]
A Physics Discovery So Strange It’s Changing Quantum Theory
MIT physicists surprised to discover electrons in pentalayer graphene can exhibit fractional charge. New theoretical research from MIT physicists explains how it could work, suggesting that electron interactions in confined two-dimensional spaces lead to novel quantum states, [...]
Inside the Nano-Universe: New 3D X-Ray Imaging Transforms Material Science
A cutting-edge X-ray method reveals the 3D orientation of nanoscale material structures, offering fresh insights into their functionality. Researchers at the Swiss Light Source (SLS) have developed a groundbreaking technique called X-ray linear dichroic orientation tomography [...]
X-chromosome study reveals hidden genetic links to Alzheimer’s disease
Despite decades of research, the X-chromosome’s impact on Alzheimer’s was largely ignored until now. Explore how seven newly discovered genetic loci could revolutionize our understanding of the disease. Conventional investigations of the genetic contributors [...]
The Unresolved Puzzle of Long COVID: 30% of Young People Still Suffer After Two Years
A UCL study found that 70% of young people with long Covid recovered within 24 months, but recovery was less likely among older teenagers, females, and those from deprived backgrounds. Researchers emphasized the need [...]
Needle-Free: New Nano-Vaccine Effective Against All COVID-19 Variants
A new nano-vaccine developed by TAU and the University of Lisbon offers a needle-free, room-temperature-storable solution against COVID-19, targeting all key variants effectively. Professor Ronit Satchi-Fainaro’s lab at Tel Aviv University’s Faculty of Medical and [...]
