Why Only Some People Get Seriously Ill from Epstein-Barr Virus: Understanding the Infection’s Impact

Epstein-Barr Virus

Epstein-Barr Virus: A Common Infection with Serious Implications

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Approximately 10% of individuals carry genetic mutations that heighten their susceptibility to the Epstein-Barr virus (EBV), a common pathogen linked to diseases like multiple sclerosis and lupus. Insights from a study involving over 700,000 participants may clarify why EBV results in severe illness for some, yet remains relatively harmless for the majority.

“Nearly everyone has encountered EBV,” explains Chris Whincup from King’s College London, who did not partake in the research. “How is it that, despite widespread exposure, only a fraction of the population develops autoimmune conditions?” This research offers plausible answers.

The Epstein-Barr virus was initially identified in 1964 when scientists detected its particles in Burkitt’s lymphoma, a type of cancer. Today, over 90% of the population has been infected with EBV, evidenced by the presence of antibodies against the virus.

Initially, EBV is responsible for infectious mononucleosis, often referred to as monofever or glandular fever, which typically resolves in a few weeks. However, it is also linked to chronic autoimmune disorders, as evidenced by a 2022 study demonstrating its role in the onset of multiple sclerosis, leading to nerve damage.

“Why do individuals exhibit such varied responses to the same viral infection?” questions Caleb Lareau at Memorial Sloan Kettering Cancer Center.

To investigate, Lareau and her research team analyzed health data from over 735,000 individuals participating in the British Biobank study and a U.S. cohort called All of Us. Their genomes were sequenced using blood samples. “When EBV infects certain cells, it leaves behind copies in the blood,” shares Lareau, indicating that the human genome in their sample includes EBV genome copies.

The research highlights substantial variability in EBV DNA levels among subjects. Of the participants, 47,452 (9.7%) exhibited over 1.2 complete EBV genomes per 10,000 cells, indicating that while many cleared the virus post-infection, this subset did not.

To comprehend the heightened vulnerability of these individuals, the research team sought specific genomic differences that correlated with high EBV levels. As noted by Ryan Dhindsa from Baylor College of Medicine, they identified 22 genomic regions linked to elevated EBV levels, many of which are previously associated with immune-mediated diseases.

The strongest correlation was found in genes related to the major histocompatibility complex, essential immune proteins in distinguishing between self and foreign cells. “Certain individuals possess mutations in their major histocompatibility complex,” Dhindsa explains. Further studies indicated that these variants may impede the immune system’s capacity to detect EBV infections.

“This virus profoundly impacts our immune system, having lasting effects on certain individuals,” comments Ruth Dobson at Queen Mary University of London. Persistent EBV DNA can subtly stimulate the immune system, potentially leading to autoimmune attacks on the body.

Moreover, the genetic variants linked to high EBV levels were associated with various traits and symptoms, notably an elevated risk for autoimmune diseases such as rheumatoid arthritis and lupus, reinforcing the hypothesis of the virus’s involvement in these conditions.

The research team also identified a connection between these mutations and chronic fatigue, intriguing given that some studies have posited EBV as a contributing factor to myalgic encephalomyelitis, commonly known as chronic fatigue syndrome (ME/CFS). Due to the large sample size, “we can assert that this signal exists,” Dhindsa remarked, although the precise relationship remains unclear.

For Wincup, the primary takeaway is the identification of immune system components damaged by continuous EBV presence. Targeting these components could lead to more effective treatments for EBV-related conditions.

Additionally, vaccination against EBV is a potential avenue. Currently, only experimental vaccines exist. Wincup emphasizes that developing a vaccine would be a significant advancement, arguing that despite its common perception as benign, EBV causes considerable suffering for many. “How benign is it really?”

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Source: www.newscientist.com

Can You Get Infected with Another Virus Alongside COVID-19? A Doctor’s Insights

As a healthcare professional, I often encounter concerns from patients about COVID-19, particularly those suffering from long-term effects. A common inquiry I receive is, “Can I get reinfected with COVID-19 while experiencing long-term symptoms from a previous infection?

Many individuals believe that enduring the virus for an extended period grants them some level of immunity against future infections. Unfortunately, this assumption is not accurate.

Long-lasting COVID-19 symptoms, including fatigue, breathing difficulties, and cognitive issues, can persist for months after initial infection. Regrettably, even prolonged exposure to COVID-19 does not shield you from reinfection.

The protective effects from previous infections and vaccinations fade over time. New variants of the virus, such as Omicron KP.3 and XEC in 2025, can evade the immune response.

This means that even if you’re grappling with persistent COVID-19 symptoms, it’s possible to contract the virus again, which may exacerbate symptoms or prolong recovery.

A positive COVID-19 test may indicate a reinfection with the same variant or a new one, but either way, it remains a manifestation of the coronavirus. Vaccines, particularly the 2025 booster shot, can significantly reduce the risk of severe illness. If you’re experiencing long-term COVID-19 and test positive, ensure you rest, stay hydrated, and consult your physician if symptoms worsen.

The coronavirus is still prevalent and continues to mutate, necessitating the practice of protective measures. It’s essential to get tested if you feel unwell, wear masks in crowded indoor settings, and keep up with vaccinations.

These proactive steps help mitigate exposure and safeguard those around you, especially as we navigate the lingering effects of this virus.


This article addresses the question from Yorkshire’s Terence Caldwell: “Can I be infected with COVID-19 along with the new variants?

If you have any questions, reach out to us at: questions@sciencefocus.com or connect with us on Facebook, Twitter, or Instagram (don’t forget to include your name and location).

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Compelling Evidence Links Epstein-Barr Virus to Lupus Development

Lupus can cause severe fatigue, rashes, and joint and muscle pain

Shahril Maulana/Alamy

The virus responsible for glandular fever, also referred to as mononucleosis or the kissing disease, has been shown to infect and modify the body’s immune cells, leading to the development of the autoimmune disease lupus in some individuals.

Lupus, or systemic lupus erythematosus, arises when the immune system becomes overly active, attacking healthy tissues due to the persistent activity of immune cells known as B cells and T cells. This can result in various symptoms such as muscle and joint pain, rashes, and profound fatigue. The exact cause of lupus remains unclear, though it likely involves a combination of genetic, hormonal, and environmental factors, including infections and microbiome imbalances.

Among those with lupus—about 90% are women—there tends to be a higher prevalence of antibodies against Epstein-Barr virus (EBV), the virus causing glandular fever. While EBV infects most adults globally and typically remains asymptomatic, lupus impacts roughly 5 million individuals worldwide.

To explore the connection, William Robinson and his team at Stanford University devised a single-cell RNA-seq technology called EBV-seq to identify which B cells (responsible for producing antibodies against pathogens) in lupus patients are infected with EBV and which genes are being expressed by those cells.

In their research, they found that in blood samples from 11 lupus patients, approximately 25 out of every 10,000 sequenced B cells were infected with EBV. Conversely, in 10 asymptomatic individuals, only up to 3 in every 10,000 sequenced B cells were found to carry the virus.

The majority of infected cells were identified as memory B cells, which retain information about previous pathogenic exposures to facilitate a quicker response upon re-exposure.

Robinson and his colleagues demonstrated that these infected memory B cells express genes such as ZEB2 and TBX21, initiating a chain reaction that activates another immune cell type known as helper T cells, subsequently recruiting uninfected B cells. This escalates immune activity in a harmful cycle, eventually beginning to target the body itself.

A significant finding affirming the causal role of EBV in lupus erythematosus was the observation that the virus seems to promote the activation of memory B cells via a protein called EBNA2. ZEB2 and TBX21 activate relevant genes and amplify their activity. “What we discovered essentially reveals how this very common virus, affecting 95% of us, the Epstein-Barr virus, leads to lupus,” says Robinson.

As for why most individuals infected with EBV do not go on to develop lupus, Robinson hypothesizes that some people have a genetic predisposition that causes their B cells to erroneously target healthy cells. “The genetic and environmental contexts of EBV infections predispose individuals to lupus, and these factors combine to provoke the disease,” he asserts.

“EBV may not be implicated in all lupus cases, due to the diverse mechanisms involved in the disease’s development. However, in specific patients, we maintain that EBV serves as a primary cause,” he explains. George Tsokos reports from Harvard Medical School: The virus instigated an abnormal T-cell response, noted in individuals with lupus over 40 years ago.

A strong correlation between EBV and multiple sclerosis, another autoimmune disorder, was identified in 2022, and Robinson suggests that these new insights highlight how the virus can trigger such conditions more broadly.

This may also clarify why certain CAR T-cell therapies have yielded promising results in lupus clinical trials. These treatments, which genetically modify a patient’s T cells to target specific antigens, were originally designed for blood cancers that arise when B cells proliferate uncontrollably and are often reduced in number. “These CAR T-cell therapies seem to result in lasting remissions. [lupus] Patients have been able to discontinue all medications, implying that the therapy might potentially even cure some individuals. We believe they may achieve this by removing [B cells] or depleting EBV-infected B cells,” Robinson suggests.

Nonetheless, Tsokos cautions that the efficacy of this therapy for lupus remains uncertain, partly because while B cell levels in the blood of patients treated with CAR T cells appear diminished, these cells can often conceal themselves in the bone marrow, and there is currently no evidence confirming that all of them are being eliminated.

The research also underscores the potential for developing a vaccine to combat the saliva-transmitted Epstein-Barr virus, which may help avert various autoimmune diseases. “Such a vaccine could be pivotal in preventing EBV infections and thereby lupus in the future,” Professor Robinson states, though he notes it would not mitigate symptoms for individuals already infected with EBV, as B cell reprogramming appears to occur shortly after infection.

Tsokos believes the broad adoption of the EBV vaccine will hinge on weighing its costs against benefits and side effects. He notes that preventing a single case of lupus might necessitate vaccinating over 1,000 individuals.

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Source: www.newscientist.com

Ukraine’s Drone Attack System Dubbed a ‘Virus’ for Its Game-Like Precision

A drone attack system resembling a computer game is “rapidly spreading” within Ukrainian military units and is being expanded to cover reconnaissance, artillery, and logistics operations, as reported by Mykhailo Fedorov, the country’s first deputy prime minister, to the Guardian.

In September, drone teams competing under the Drone Corps Bonus System were credited with killing or injuring 18,000 Russian soldiers, with participation growing from 95 to 400 drone squads within one month, according to Ukrainian officials.

This system, initiated over a year ago, rewards soldiers for successful strikes by awarding points that can be exchanged for additional weapons from an online store dubbed Brave1, which features over 100 types of drones, self-driving vehicles, and various drone warfare equipment. Teams with creative names such as Achilles and Phoenix currently lead the scoreboard.




Brave1 online store. Photo: https://market-brave1.delta.mil.gov.ua/katalog/filter/icons=11;page=3;presence=1/

Fedorov noted that the system has gained “tremendous popularity among troops” and exemplifies the growing automation in combat. “The Defense Forces are all aware, and there’s a competition for points to acquire drones, electronic warfare systems, and other equipment that enhances combat effectiveness. The more infantry you take down, the more drones can eliminate additional infantry. It’s becoming a self-sustaining cycle.”

Russian casualties in September were reported to be double those of the previous October, partly due to the Ukrainian government increasing the points awarded for killing Russian infantry from six to twelve, highlighting shifting battlefield priorities.

Ukrainian intelligence suggests that Russia might be developing its own version of this gamification approach. Additionally, Ukraine is expanding the Destroy Points concept to artillery units, providing them with success points that can be used to acquire new armaments. Reconnaissance teams are also earning points for identifying enemy targets, while logistics units are beginning to gain points for utilizing self-driving vehicles in front-line resupply efforts.

Fedorov disclosed that the Ukrainian military is promoting the use of drones partially directed by artificial intelligence, enhancing target selection and controlling the final moments of the drones’ trajectory to boost attack precision.

Scouts accumulate points through a system dubbed “Uber targeting,” reminiscent of the global ride-hailing app.

“Essentially, you drop a pin on a map similar to requesting a ride on an Uber app, but in this case, a drone from a different unit engages the target,” he explained.

Despite the point-based system’s expansion, there are warnings that over-reliance on drone warfare may not be a model for NATO countries to emulate, as Russian defenses against such aerial attacks have become significantly robust. Experts from the Royal United Services Institute have recently highlighted the need for renewed focus on conventional artillery and air support.

In addition to raising the points for infantry kills to align with Russia’s increased deployment of infantry, killing an enemy drone operator grants 25 points, while capturing a Russian soldier with a drone nets 120 points, reflecting Ukraine’s need for prisoners of war for potential exchanges. Although these point values have received official approval, Fedorov mentioned they have become “almost devoid of emotion” in assigning value to human life.

“We’ve been engaged in a war for four consecutive years and it’s been challenging,” he stated. “We aim to enhance effectiveness. We perceive this as part of our regular operations. It’s largely devoid of emotional contemplation. It resembles technical work because if we don’t halt the enemy, they will kill military personnel, and once that happens, they will come for civilians—conquering, destroying, and killing.”

Ukrainian drone operators may be positioned as close as 250 meters to the front lines or as far as three kilometers away, often concealed behind computer screens while directing assaults, sometimes utilizing video game controllers. Achilles is recognized as one of the top 10 successful drone regiments, operating in the eastern Kharkiv and Donetsk regions. Commander Yuri Fedorenko noted that the most effective pilots are not necessarily those skilled in video games.

“The best pilots are those with discipline,” he remarked. “Younger individuals may be able to stay awake longer and require less recovery time, but discipline is the hallmark of a good drone operator.”

He also downplayed the notion that this initiative amounts to the “gamification” of warfare, stating that directives are sometimes issued to target low-point objectives to meet immediate combat needs.

“This is war, so our primary focus must be on completing the mission,” he said. “That’s our priority, not chasing points.”

“There’s competition across the unit. Drone operators are in competition with one another. Groups of drone operators compete against other groups. Even the highest-ranking commanders engage in competition,” explained Andrii Poltolatskyi, another commander in the drone unit.

He characterized it more as a constructive competition than a playful one, noting that when Russia initiates an attack, “the competition ceases and everyone… collaborates towards the goal of protecting Ukrainian lives, irrespective of the points involved.”

Fedorov stated that the scoring system has provided valuable data, enhancing Ukraine’s “understanding of the mathematics of war.”

“Thanks to the points, we are beginning to comprehend the realities of the battlefield,” he mentioned. “To earn points, [drone units] must submit a verification video. This way, we gain insights into the targets being engaged, their locations relative to the contact line, and the drones and other assets being utilized.

“This enables us to evaluate what strategies are proving effective and which are not. The leaderboard encourages units to learn from each other. Leaders are beginning to mentor and cultivate emerging talent… Innovation emerges from the ground up.”

Source: www.theguardian.com

Herpes Virus Could Be Fast-Tracked for Treating Severe Skin Cancer

Melanoma is a form of skin cancer that can metastasize

Science Photo Library

After years of research and extensive human trials, only one virus specifically engineered to target cancer has gained approval from US and European regulators. Following promising results in treating melanoma—a notably aggressive skin cancer—approval may soon be granted.

The genetically altered herpes virus, known as RP1, was injected into the tumors of 140 patients with advanced melanoma who did not respond to conventional treatments. All participants also received a medication called nivolumab, designed to enhance the immune response against the tumors.

In 30% of the treated individuals, tumors shrank, including those that were not directly injected. Notably, in half of these cases, the tumors were completely eradicated.

“Half of the patients who responded experienced a complete response, meaning total disappearance of all tumors,” said Gino Kim from the University of Southern California. “I am thrilled with these results,” he added, noting that other treatments for patients at this stage often perform poorly and have harsher side effects.

A larger trial involving 400 participants is currently in progress; however, RP1 may receive approval from the US Food and Drug Administration (FDA) to be used in conjunction with Nivolumab for treating advanced melanoma before the trial concludes. The New Scientist reports that “the FDA is anticipated to make a decision by the end of this month.”

For over a century, it has been recognized that viral infections can aid in cancer treatment, though intentionally infecting someone with a “wild” virus poses significant risks. In the 1990s, scientists attempted to genetically modify viruses to effectively target cancer while leaving healthy cells unharmed.

These engineered viruses function in two main ways: First, they directly invade cancer cells, causing them to rupture and die. Secondly, they stimulate immune responses aimed at all cancer cells present in the body.

For instance, T-VEC, a modified herpes simplex virus, was engineered to release an immune-boosting factor called GM-CSF within infected tumor cells. T-VEC received approval in 2015 in both the US and Europe for treating inoperable melanoma.

Unfortunately, T-VEC’s use is limited as it was only tested and approved for injection into skin tumors. Many patients with advanced melanoma have deeper tumor locations, as noted.

With RP1, the strategy shifted to administering it into deeper tumors. RP1, like T-VEC, is a herpes simplex virus but has undergone various enhancements. It notably aids in fusing tumor cells with adjacent ones, thus boosting viral spread within the tumor and reinforcing the immune response.

Though there have been no direct comparisons between T-VEC and RP1, RP1 demonstrates a greater likelihood of reducing all tumors, rather than just those directly injected. “It indicates a more pronounced systemic effect,” experts state.

Thus, should RP1 gain approval, its application is expected to be far broader than that of T-VEC. Experts believe this could significantly enhance the overall interest in utilizing cancer-targeting viruses. “There seems to be increasing enthusiasm for this approach.”

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Source: www.newscientist.com

A Silent Virus Rapidly Alters Our Genome and Enhances Its Growth

Human DNA within cells in its natural state (left) contrasted with its state eight hours after cold sore virus infection (right)

Esther Gonzalez Almera and Alvaro Castells Garcia

Viruses that typically cause herpes can reform their genome within an hour following infection, potentially allowing scientists to address severe cases more effectively.

Billions globally are infected by Herpes Simplex Virus Type 1 (HSV-1), often without their knowledge. Transmission occurs via contact with infected saliva or skin around the mouth.

Upon invading a host cell, the virus replicates within the nucleus, where genetic material is preserved among the strands of DNA. These strands surround proteins, with some sections tightly coiling to deactivate genes while others form looser loops where genes remain active. In these less dense areas, proteins can transcribe DNA into messenger RNA, encoding for a protein essential for cellular function.

Prior research has indicated that the human genome becomes more tightly coiled following HSV-1 infection, possibly disrupting cellular functions, although the cause of this coiling was previously uncertain.

For further details, consult Alvaro Castells-Garcia at the genome regulatory center in Barcelona, Spain, whose team employs advanced microscopy to investigate HSV-1, infecting human lung cells and observing structures that are 3,500 times thinner than a hair. “This offers a higher resolution than most prior studies,” notes Castells-Garcia.

They discovered that within an hour post-infection, transcription factors were already pilfered from the human genome, corroborating previous findings.

Moreover, this thievery is what appears to cause the host’s DNA to coil more tightly, compressing it to 30% of its volume within 8 hours of infection.

The virus also interacts with specific areas of the host genome that encode the stolen transcription factors, inhibiting activity in those regions and enhancing the expression of genes that facilitate its own growth.

“Previously, I thought the virus made random contacts with the genome,” comments team member Esther Gonzalez Almera at the genome regulation center. “However, it’s clear that viruses specifically target certain regions of their genome, which often contain genes critical to sustaining the infection and producing viral RNA and proteins.”

In another segment of the study, researchers found that utilizing experimental cancer treatments to obstruct one of the transcription factors taken by HSV-1 inhibited its replication in human lung cells in the laboratory. This suggests that such medications could assist in treating HSV-1 in individuals suffering from severe herpes outbreaks and those at higher risk for complications, as González-Almela explains. Mild cases typically resolve without intervention.

This treatment may also be effective against other pathogens, such as adenoviruses that lead to colds, and noroviruses associated with gastroenteritis. “Other viruses similar to HSV-1 may employ analogous strategies,” states Benjamin Krishna from Cambridge University. “These could represent [potential types of experimental drugs] for addressing such cases as well,” he adds.

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Source: www.newscientist.com

West Nile Virus Identified in British Mosquito for the First Time

A fragment of the virus has been identified in Aedes aegypti mosquitoes in Nottinghamshire, UK

IMV/ISTOCKPHOTO/GETTY IMAGES

The West Nile virus, marking the first potential fatal mosquito-borne disease in the UK, has been identified for the first time.

The UK Health Security Agency (UKHSA) has announced that its research collaboration with the Animal and Plant Health Agency has Afa successfully identified a “fragment” of the virus in Aedes aegypti mosquitoes collected from the marshlands along the Idol River in Nottinghamshire in July 2023, indicating that these insects are carriers of pathogens.

According to Alanfolly from Apha, the virus was discovered somewhat by chance during routine testing by his team. He notes that further screenings will take place around that area later this year. Interestingly, Nottinghamshire typically does not fall into Afa’s primary testing regions, which are mostly centered in southern and eastern England, where warmer climates increase the likelihood of infections such as West Nile.

Humans and horses can become infected with the West Nile virus through mosquito bites. Approximately 20% of infected individuals exhibit symptoms such as fever, headaches, body aches, vomiting, and diarrhea. In rare instances, the virus can lead to severe inflammation of the brain and spinal cord, which can be fatal. Currently, there are no approved vaccines for humans.

UKHSA has reported the virus’s presence only in two mosquito samples, with no current evidence suggesting that humans or horses are infected in the UK. The organization’s assessment indicates a very low risk to the public, but healthcare professionals are advised to test encephalitis patients for unexplained causes.

“This is the first identification of the West Nile virus in British mosquitoes, though it doesn’t come as a surprise given the virus’s ongoing spread across Europe,” stated Meera Chand from UKHSA.

The West Nile virus has been increasingly observed in Africa, Europe, and North America. In Europe, recent years have seen its northern spread, reaching the Netherlands in 2020.

Factors contributing to the spread of the West Nile virus include elevated spring and summer temperatures, summer droughts, and milder winters, all of which are becoming more prevalent in Northern Europe. Although APHA has not detected the West Nile virus in mosquitoes or birds for 2024, the recent warm weather in the UK could change that. “We had an unusually warm May,” Folly noted. “If there is another case, we may see it in the coming weeks. This is just the beginning; more cases could follow.”

British researchers have been vigilant for the West Nile virus since 2020 when a related mosquito-borne virus (USUTU) was first found in London. The West Nile virus shares similar transmission characteristics with USUTU and requires comparable environmental conditions.

“I wouldn’t be surprised at all,” stated Matthew Baylis from the University of Liverpool. “I’ve been expecting this to happen every year. I believe that the West Nile virus will eventually be detected in the UK.”

He suggested that the virus likely arrived in the UK via birds and is probably circulating among various mosquito species in the region. However, he reassured that there is no immediate cause for alarm. “The risk remains low for most people. While a few horses are susceptible to West Nile disease, it’s quite rare,” he added.

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Source: www.newscientist.com

Outbreak of H5N1 virus causing bird deaths in Antarctica

Antarctic adelie penguins are under threat from bird flu

Steve Bloom Images/Aramie Stock Photos

H5N1 bird flu was first discovered in a dead bird in Antarctica. Fatal tensions in avian flu are currently spreading south along the Antarctic Peninsula, with devastating consequences for wildlife such as penguins and could spread across the continent.

“It’s scary. Luckily, it only affects a few. [birds]”I say Juliana Viana at the Pope Catholic University of Chile in Santiago. “I hope it stays that way, but the bird flu in Chile and Peru was a disaster. It killed thousands of seabirds and sea lions.”

Between November 2024 and January 2025, Vianna’s team investigated 16 nesting sites for seabirds along the Antarctic Peninsula. Researchers found 35 dead Skuas with no signs of injury. Samples from 11 bodies were found to be positive for the highly pathogenic H5N1 avian influenza virus that has spread around the world in recent years.

Skuas removes corpses and is ahead of other birds, so eating infected birds is particularly likely to cause infection. Skuas in this area are hybrids between the Antarctic (Stercorarius Maccormicki) and brown (Stercorarius Antarcticus)SKUAS.

So far, no other species of birds have been confirmed, but Vianna says she was also said to have been found dead on March 9th. “We spoke with the Chilean Antarctic Institute,” she says. “They saw the dead squau and the penguin.”

As penguins breed in dense colonies, there is a fear that H5N1 spreads rapidly between them, killing most of several groups. Some penguin species may be resistant, as birds’ susceptibility to H5N1 varies from species to species, Vianna said.

The highly pathogenic form of H5N1 avian influenza has been circulating in Europe, Asia and Africa since 2020, killing many wild birds and causing outbreaks on poultry farms. For example, in the UK, H5N1 was killed A quarter of Gannett 2023.

In 2021, it arrived in North America and was later found to infect dairy cows’ breasts and spread between them. By the end of 2022 it had spread to the southern tip of South America, killing thousands of marine mammals and many different species of birds along the way.

The sick brown squat and giant plaster on Bird Island, just off a large island in South Georgia, tested positive for the virus in 2023. South Georgia is approximately 1,500 km from the Antarctic Peninsula.

Vianna’s team in December 2023 and January 2024 Signs of infection discovered in some living Adelie penguins and Antarctic shags At the northernmost tip of the peninsula. The presence of viruses on the continent has now been confirmed.

“Reported deaths of SKUAS are of concern,” he says. Thijs Kuiken At Rotterdam, the University of Erasmus, Netherlands. Some species in the area are only found on small islands and could be wiped out by avian flu, he says.

However, the tests described in Vianna’s study only show that SKUA has been infected with H5 influenza, and Kuiken does not know whether it is a highly pathogenic form.

Vianna says that’s correct, but samples were sent for additional tests not detailed in the paper. “So it’s been confirmed as a highly pathogenic avian flu,” she says.

On February 25th, another group of researchers reported Find H5N1 in the Closet and Kergellen archipelago In the Indian Ocean near Antarctica, where the virus killed elephant seals and several species of birds. That is, the virus moved towards Australia and New Zealand along the way in Antarctica. This is the only major country that is free from the virus.

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Source: www.newscientist.com

The Death of a Blackbird highlights the looming danger of the West Nile virus in the UK

Blackbird numbers have decreased in the UK as the USUTU virus has taken hold

ytje veenstra/shutterstock

The deadly virus is killing Blackbirds all over the UK. Beyond the risks for birds, its spread indicates that mosquito-borne viruses are currently pose a threat to humans and animals in the country as a result of climate change.

The virus in question, USUTU, occurred in South Africa in 1959, but is now spreading in Europe. It caused fatal diseases in certain birds, especially black swans, and was first detected in the UK in 2020. In some parts of the country, the Blackbird population, the most notable London, has fallen by more than 40% since 2018. “I first noticed a decline when USUTU popped up,” he says. Hugh Hammer With British trust for ornithology.

Though catastrophic to bird life, USUTU poses low risks to humans and mammals. Human infectious diseases are rare and generally cause mild fever, but the arrival of the virus in the UK marked the first time by mosquito-borne viral zoonotic diseases (a disease that can be transmitted from animals to humans) that have appeared in domestic animal hosts. Virus experts are closely monitoring how well and fast the disease is spreading, as it could be a template for the future spread of other mosquito-borne diseases.

For example, the West Nile virus spreads just like USUTU and requires the same environmental conditions. “The same mosquitoes that can send USUTUs can usually send West Nile. [for Usutu] It can also serve as a host for West Nile.” Alanfolly at the British Animal and Plant Health Organization (APHA).

Humans can also contract the West Nile virus when bitten by mosquitoes, but the symptoms can be more severe than those of USUTU. Approximately 20% of infected people experience symptoms including fever, headache, body pain, vomiting and diarrhea. In rare cases, this virus can cause serious inflammation of the brain and spinal cord, which is fatal. There are no known human vaccines.

Climate change has helped accelerate the spreading of the West Nile virus through Northern and Eastern Europe. Research Showas the virus thrives in warm summer temperatures. In the Netherlands, USUTU was first detected in 2016, and the West Nile virus continued in 2020. British officials fear a similar pattern will unfold in their country. Demonstrating research The climate there is becoming more and more kind to mosquito-borne viruses. “The idea is if there's usutu here, West Nile is likely to come at some point and last, given the right conditions,” Folly says.

In response to the threat, APHA launched a project in 2023 to track the emergence and transmission routes of USUTU and other mosquito-borne viruses in wild birds. Infrastructure to track this virus It is essential for the country to respond quickly to West Nile's arrival, Foley says. “Our real goal, or willingness from a government perspective, is to be able to detect these. [new viruses] We circulate animal populations before they can be transmitted to humans. ”

Reina Sikkema The University of Erasmus Medical Center in Rotterdam is studying the emergence of the Netherlands Ustus and the West Nile virus. The West Nile has not been detected since 2022,He believes the virus is circulating at low levels and is now being controlled by a relatively cool climate. “I believe it exists, but it takes the right situation to burn,” she says. Sikkema said detection of the West Nile in the UK is now inevitable, but he believes similar climatic factors can prevent the virus from spreading too widely.

However, the temperature rise in summer including Increased frequency of tropical nights – The UK's Met Office Weather Agency defines Sikkema that if the minimum temperature is not below 20°C, it could change photos of the UK, the Netherlands and other Northern European countries. “Mosquito-borne is not [just] On your Spanish holiday, or when you go to South America,” says Folly.

Like the potential risk of the West Nile virus to people, Folly says we shouldDon't forget what USUTU is doing to Blackbirds in the UK: “If 40% of humans die in Greater London, you'll know about it very quickly.”

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Source: www.newscientist.com

Ionizing radiation from nearby supernovae impacted the evolution of the virus 2.5 million years ago

This supernova event may have occurred at the Upper Centaurus Lupus Society. This is a group of giant stars about 457 light years away from Earth.

Illustration of an exoplanet like Earth after X-ray radiation exposure. Image credit: NASA/CXC/M. Weiss.

Life on Earth is constantly evolving under continuous exposure to ionizing radiation from both terrestrial and cosmic origins.

The radioactivity in the bedrock gradually decreases over timescales of billions of years, but the level of cosmic radiation fluctuates as the solar system moves through the Milky Way.

Nearby supernova activity could increase the level of radiation on the Earth’s surface by several orders of magnitude, which is expected to have a major impact on the evolution of life.

In particular, radiation levels improve as the solar system passes near a large group of stars known as the OB Association.

The winds associated with these large star factories are expected to inflate the super bubbles of high temperature plasma first. This could be the birthplace of most of the Core Collapse explosions taking place within the AB Association.

The solar system entered such a super bubble, commonly known as the local bubble, about 6 million years ago, and is now close to its centre.

“The Earth entered the local bubble and passed its stardust-rich appearance about 6.5 million years ago, sowing the planet with old iron 60, the radioactive iron of iron produced by the exploding stars. did it,” astronomer Santa Cruz, and colleagues at the University of California.

“Then, 20-3 million years ago, one of our neighboring stars exploded with incredible force, providing another cohort of radioactive iron to the planet.”

When Nojiri and her co-authors simulated what the supernova looked like, they discovered that it hammered the Earth with cosmic rays for 100,000 years of explosion.

This model perfectly described previously recorded spikes of radiation that shocked the Earth around that time.

“We’ve seen from other papers that radiation can damage DNA,” Nojiri said.

“It could be an evolutionary change in the cell or an accelerated mutation.”

Meanwhile, the author came across research into viral diversity in one of the Rift Valley Lakes in Africa.

“I can’t say they’re connected, but there are similar time frames,” Nojiri said.

“We found it interesting that the virus’s diversification is increasing.”

study It was published in Astrophysics Journal Letter.

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Caitlyn Nojiri et al. 2025. Bubble Life: How nearby supernova left short-lived marks on the cosmic ray spectrum, leaving an indelible trace of life. apjl 979, L18; doi: 10.3847/2041-8213/ADA27A

Source: www.sci.news

Mpox: Understanding the Fatality Rate and Treatment Options of the Virus

Health workers assess a suspected case of MPOX in North Kivu province, Democratic Republic of Congo.

Arlette Basij/Bloomberg via Getty Images

Mpox, formerly known as monkeypox, is currently in the midst of an outbreak in the Democratic Republic of Congo (DRC) and neighboring countries, with the surge in cases being blamed in part on a new variant that is thought to be more deadly than the variant of the Mpox virus that caused a global outbreak in 2022. But there are treatments that may help.

How deadly is MPOX?

Studies have shown that the mortality rate among people infected with the currently circulating lineage I variant of MPOX is approximately 1-2%. 11 percentThe variation in reported mortality rates is probably due to differences in affected populations and problems with disease surveillance, Lilith Whittles At Imperial College London.

For example, infants and children with underdeveloped immune systems may be more likely than adults to develop serious, even fatal, infections, and people with suppressed immune systems, such as those with HIV, may also be more susceptible, she says.

Additionally, some areas have little access to health care and limited surveillance for MPOX. As a result, health care providers only catch the most severe cases and miss milder cases, making the death rate appear higher than it actually is. If MPOX symptoms are increasingly misdiagnosed as other illnesses, like measles or chickenpox, more cases will go undetected, Whittles says.

In fact, most deaths from MPOX occur due to complications such as sepsis, where infection enters the bloodstream and causes organ failure, and inflammation caused by the MPOX virus that damages the lungs, he said. Piero Oriaro At Oxford University.

What are the MPOX treatment options?

In the Democratic Republic of Congo and neighboring countries where the current outbreak is occurring, there are few treatments specific to MPOX. Instead, doctors focus on treating symptoms, which usually last two to four weeks, such as reducing fever and headaches with paracetamol (acetaminophen) and cleaning skin lesions to prevent bacterial infections, he said. Jean-Claude Udahemka At the University of Rwanda.

In the UK and US, doctors can use the antiviral drug Tecovirimat to treat people with severe smallpox. Originally developed to treat smallpox, its use against the disease was based on animal studies in which it improved survival rates compared to a placebo. Tecovirimat works by binding to a protein on the surface of both variola and smallpox that the virus uses to attack. Freeing itself from infected cells spreads to other cells.

Doctors in the United States and the United Kingdom can also treat MPOX with other antiviral drugs, such as brincidofovir and cidofovir. Protecting mice from lethal doses of the mpox virus. Both brincidofivir and cidofovir Interfering with enzymes Used by viruses to replicate their genome.

Another treatment, known as VIGIV, involves injecting people with smallpox with antibodies against smallpox taken from people who have had the smallpox vaccine, thus strengthening their immune response to the virus.

How effective is mpox treatment in humans?

Animal studies suggest that these treatments may be effective against MPOX, but their effectiveness in humans is unknown. Early results from a recent randomized controlled trial (best medical evidence) in the Democratic Republic of Congo suggest that tecovirimat does not accelerate the progression of MPOX. Healing of painful lesions in children and adults infected with lineage I variants of MPOX.

Nonetheless, the researchers found that the MPOX mortality rate for participants who received the antiviral drug was 1.7 percent, an improvement over the 3.6 percent mortality rate typically seen in the Democratic Republic of Congo. But this can be partly explained by the fact that participants in the trial received close care in hospital, Oriaro says.

Ultimately, better treatments and a better understanding of MPOX's lethality will be essential to protect people, especially in the Democratic Republic of Congo, from the ongoing epidemic. Lucille Blumberg She is a researcher at the University of Pretoria in South Africa. “There's a lot of work to be done,” she says.

topic:

  • virus/
  • Infection

Source: www.newscientist.com

Study reveals high prevalence of SARS-CoV-2 virus among wild animals

In a new study, a team of scientists from Virginia Tech investigated the extent to which exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, was widespread in wildlife communities in Virginia and Washington, DC, between May 2022 and September 2023. They documented positive detection of SARS-CoV-2 RNA in six species: deer mice, Virginia opossums, raccoons, groundhogs, cotton-tailed bats, and eastern red bats. They also found no evidence that the SARS-CoV-2 virus was transmitted from animals to humans, and people should not fear general contact with wildlife.



Goldberg othersThis suggests that a wide variety of mammal species were infected with SARS-CoV-2 in the wild. Image credit: Goldberg others., doi: 10.1038/s41467-024-49891-w.

“SARS-CoV-2 could be transmitted from humans to wild animals during contact between humans and wild animals, in the same way that a hitchhiker might jump to a new, more suitable host,” said Carla Finkelstein, a professor at Virginia Tech.

“The goal of a virus is to spread in order to survive. It wants to infect as many humans as possible, but vaccination protects many of us. So the virus turns to animals, where it adapts and mutates to thrive in a new host.”

SARS CoV-2 infections have previously been identified in wild animals, primarily white-tailed deer and wild mink.

This new research significantly expands the number of species investigated and improves our understanding of virus transmission in and between wild animals.

The data suggest that exposure to the virus is widespread among wild animals and that areas with high human activity may be contact points for interspecies transmission.

“This study was prompted by the realization that there were significant and important gaps in our knowledge about the transmission of SARS-CoV-2 in the broader wildlife community,” said Dr. Joseph Hoyt of Virginia Tech.

“Most studies to date have focused on white-tailed deer, but we still don't know what's going on with many of the wildlife species commonly found in our backyards.”

For the study, the researchers collected 798 nasal and oral swabs from animals that had been caught live and released from the wild, or that were being treated at a wildlife rehabilitation center, as well as 126 blood samples from six animal species.

These sites were chosen to compare the presence of viruses in animals across different levels of human activity, from urban areas to remote wilderness.

The scientists also identified two mice with the exact same mutation on the same day and in the same location, indicating that they either both got infected from the same person, or one had transmitted it to the other.

How it spreads from humans to animals is unknown, but wastewater is a possibility, but trash cans and discarded food are more likely sources.

“I think the biggest takeaway from this study is that this virus is everywhere. We're finding it in common backyard animals that are testing positive,” said Dr. Amanda Goldberg of Virginia Tech.

“This study highlights the potentially broad host range of SARS-CoV-2 in nature and how widely it may actually spread,” Dr Hoyt said.

“There is much work to be done to understand which wildlife species, if any, are important in the long-term maintenance of SARS-CoV-2 in humans.”

“But what we've already learned is that SARS CoV-2 is not just a human problem, and we need multidisciplinary teams to effectively address its impacts on different species and ecosystems,” Professor Finkelstein said.

of Investigation result Published in today's journal Nature Communications.

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A.R. Goldberg others2024. Widespread exposure to SARS-CoV-2 in wildlife communities. Nat Community 15, 6210; doi: 10.1038/s41467-024-49891-w

This article has been edited based on the original release from Virginia Tech.

Source: www.sci.news

What unfolded after scientists revived an ancient virus from suspended animation?

Permafrost is ground that is always frozen, and the possibility of life existing there is believed to be low. However, in recent years, Scientists have discovered an abundance of microorganisms that are still alive despite being frozen in permafrost.

Various viruses, including one called Pandoravirus, have been found frozen. Researchers have been able to revive a frozen Pandoravirus that only infects amoebas from 30,000-year-old permafrost in Siberia.


More concerning viruses, such as strains of influenza that caused the 1918 pandemic, have also been discovered. The smallpox virus was found in a 300-year-old Siberian mummy, but the virus was no longer infectious as its genome was degraded.

Scientists have found these microorganisms frozen in the permafrost. – Image credit: Getty

Most viruses cannot survive long outside a host, reducing the likelihood of still-infectious human viruses in permafrost. Rather, the discovery of viruses infecting other microbes, like bacteria adapted to extreme environments, is more probable.

Some living bacteria found in permafrost over a million years old can still cause illness. The anthrax outbreak in Siberia in 2016 killed humans and animals, likely due to melting permafrost exposing the bacteria.

Bacillus anthracis is a type of bacteria that can form spores enabling survival in harsh environments. Climate change-induced permafrost melting may lead to ancient microbe outbreaks, but the emergence of new viruses causing global pandemics from permafrost is unlikely.

This article addresses the question of how a virus can survive in ice for many years, posed by Roy Meddings in an email.

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Source: www.sciencefocus.com

Biologists find ancient giant virus inserted into genome of a single-celled parasite

Amoebidium appalachenseViruses in protists closely related to animals weave remnants of ancient giant viruses into their genetic code, according to a new study led by Queen Mary, University of London. The discovery sheds light on how complex organisms acquire parts of their genes and highlights the dynamic interplay between viruses and their hosts.

Amoebidium appalachense A unique model for understanding the hybrid origin of eukaryotic DNA. Image courtesy of Alex de Mendoza.

In this study, Dr. Alex de Mendoza Soler and his colleagues Amoebidium appalachense A unicellular parasite first isolated from the epidermis of a freshwater arthropod.

They found a surprising amount of genetic material from giant viruses, some of the largest known to science.

The sequences of these viruses are highly methylated, a chemical tag that often silences genes.

“It's like a hidden Trojan horse. Amoebidium appalachense It’s the DNA of,” says Dr. de Mendoza Soler.

“These viral insertions are potentially harmful, but Amoebidium appalachense It seems like we are suppressing them by chemically silencing them.”

The researchers then investigated how widespread this phenomenon may be.

They are some Amoebidium appalachense Examination of the isolates revealed wide variation in viral content.

This suggests that the processes of viral integration and silencing are continuous and dynamic.

“These findings call into question our understanding of viruses and the relationship between them and their hosts,” said Dr de Mendoza Soler.

“Traditionally, viruses are thought of as invaders, but this study suggests a more complex story.”

“Viral insertions may have played a role in the evolution of complex organisms by contributing new genes.”

“And this can be done by chemically controlling the invader's DNA.”

moreover, Amoebidium appalachense It shows intriguing parallels to how our own genomes interact with viruses.

It's similar to Amoebidium appalachense Humans and other mammals carry remnants of ancient viruses called endogenous retroviruses built into their DNA.

These remnants were previously thought to be inactive junk DNA, but now it appears some may be beneficial.

but, Amoebidium appalachense Endogenous retroviruses are much smaller, while the human genome is significantly larger.

Future studies can explore these similarities and differences to understand the intricate interactions between viruses and complex life forms.

Team Investigation result Published in today's journal Scientific advances.

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Luke A. Saleh others 2024. DNA methylation enables recurrent internalization of giant viruses in animal relatives. Scientific advances 10(28); Source: 10.1126/sciadv.ado6406

This article has been edited from an original release from Queen Mary, University of London.

Source: www.sci.news

Las Vegas sees surge in mosquitoes carrying West Nile virus

summary

  • A record number of mosquitoes in and around Las Vegas are testing positive for the West Nile virus as mosquito populations across the region soar.
  • Local health officials are urging residents to take precautions to avoid being stung.
  • The situation in Las Vegas is a case study as climate change expands the reach of vector-borne diseases.

Record numbers of mosquitoes are carrying the West Nile virus in and around Las Vegas, prompting local health officials to issue a public warning. Take precautions To avoid getting bitten.

West Nile virus causes fever, headache, vomiting and diarrhea and is fatal in about 1 in 150 cases. There is no vaccine or medicine to treat or prevent the mosquito-borne disease.

In recent weeks, 169 of more than 24,000 mosquito swarms tested for West Nile virus in 25 Southern Nevada ZIP codes tested positive, meaning at least one mosquito in the swarm was carrying the virus. The number of mosquitoes and positive swarms recorded this early in the season broke the regional records for both indicators set in 2019.

“The mosquito population is huge and we've already seen significant numbers of mosquitoes carrying the West Nile virus,” said Vivek Raman, environmental health inspector for the Southern Nevada Health Department.

Health officials also identified six swimming pools in the Las Vegas area where people had tested positive for the St. Louis encephalitis virus, a mosquito-borne disease that causes potentially fatal inflammation of the brain.

For decades, climate scientists and public health officials have warned that climate change could increase the range of various infectious diseases, particularly those transmitted by mosquitoes. The Las Vegas mosquito surge and regional increase in West Nile virus outbreaks provide an important case study in how climate affects human health.

Climate change will increase the global average temperature and precipitation, creating ideal conditions for mosquitoes, who breed in still, warm water. It will also lengthen the warm season, lengthening the mosquito season. These changes will Human exposure risk Even in places where no cases have been recorded before, there is an increased risk of contracting diseases such as West Nile virus.

The first case of West Nile virus was recorded in Las Vegas in 2004, five years after the first case in the United States was recorded in New York City in 1999. The most recent West Nile virus outbreak in Las Vegas was five years ago, when 43 people were infected, and area health officials fear the situation could get even worse this summer.

Spring weather is coming to Nevada and much of the Southwest. It gets warmer Summer heat waves have become more intense in recent decades. In Las Vegas, the average spring temperature is 6.2 degree increase since 1970This month, the city has already A week of record-breaking heatwave.

Rising temperatures in Southern Nevada are creating favorable conditions for mosquitoes, said Nishay Mishra, an assistant professor of epidemiology at Columbia University. Additionally, the state's ongoing drought has lowered groundwater levels throughout the Colorado River basin, including Lake Mead, which could unexpectedly benefit the insects.

“Mosquitoes typically breed in places that are moist and hot,” Mishra says, “but in Nevada, when small bodies of water dry up, they create shallow water that's perfect for mosquito breeding.”

Las Vegas' mosquito surge has been enormous: Last year, local health officials counted 6,000 mosquitoes in traps set across Clark County between April and June. This year, the number is already over 24,000.

Most of these mosquitoes are Culex mosquitoes, which are the primary vectors of the West Nile virus. But another mosquito species that doesn't carry the virus, Aedes aegypti, has also become common in Las Vegas. It was first spotted in the area in 2017, and Raman attributes its spread in part to climate change.

Along with climate, human behavior also plays an important role in the spread of vector-borne diseases. Culex mosquitoes and Culex pipiens mosquitoes breed in many Las Vegas backyards, the former breeding in small pools of water such as those left by sprinklers, and the latter often breeding along the surface of untended swimming pools.

Raman said the best ways to prevent infection are to empty water containers outside, take care of swimming pools, wear protective clothing and use bug repellent to prevent insect bites.

Louise Ivers, professor of global health and social medicine at Harvard Medical School and director of the university's Global Health Institute, said situations like the one in Las Vegas will become more common as infectious diseases continue to rise around the world due to climate change.

“We expect to see new infections, the resurgence of old ones, and changes in the transmission patterns of existing ones like West Nile virus,” Ivers said. “We may no longer be able to do things that we were previously free to do without worrying as much about protection from vectors like mosquitoes and ticks.”

Source: www.nbcnews.com

Scientists find colossal virus in Greenland ice samples

Giant viruses were first discovered in the ocean in 1981, when researchers discovered them. These viruses were specialized to infect green algae in the sea. Giant viruses were later found in soil on land and even in humans. However, this is the first time that giant viruses have been found living on the surface of ice or snow, where snow algae dominate. In Greenland, these viruses probably control the growth of snow algae by infecting them on the ice.

Giant virus species Pandoravirus Salinus Image courtesy of IGS CNRS-AMU.

“Every spring in the Arctic, the sun rises after months of darkness and life returns,” said Aarhus University researcher Laura Perini and her colleagues.

“Polar bears emerge from their winter dens, arctic terns return from their long journey south, and musk oxen trek north.”

“But animals aren’t the only life awakened by the spring sun. Algae that were dormant on the ice begin to flourish in the spring, turning large areas of the ice black.”

“As the ice darkens, it loses its ability to reflect sunlight, which accelerates its melting. More melting exacerbates global warming.”

“But we may have found a way to control the growth of snow algae, and in the long term, we may be able to reduce some of the ice melt.”

In the new study, the authors found signatures of giant viruses in snow and ice samples from the Greenland Ice Sheet.

The researchers believe that these viruses feed on snow algae and may act as a natural control mechanism against algal blooms.

“Although we still do not know much about viruses, we suspect they may be useful as a means to mitigate ice melt caused by algal blooms,” the researchers said.

“We don’t yet know how specific it will be and how efficient it will be, but we’re hopeful that further investigation will help answer some of those questions.”

“We analyzed samples of black ice, red snow, and melted pits (cryoconite),” they explained.

“We found traces of an active giant virus in both the dark ice and the red snow.”

“And this is the first time they’ve been found on ice or snow surfaces that are rich in pigmented microalgae.”

“The ecosystem surrounding the algae includes bacteria, fungi, and yeasts, as well as protozoans that eat the algae, various fungi that parasitize the algae, and giant viruses that infect the algae.”

“These last three groups need to be studied to understand the biological controls that act on algal blooms.”

“We can’t pinpoint which hosts the giant viruses will infect. Some of the viruses may infect protists, others may attack snow algae. We don’t know for sure yet,” Dr Perini said.

“We are continuing our research to learn more about giant virus interactions and their role in the ecosystem.”

Team paper Published in the journal Microbiome.

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L. Perini other2024. Traces of a giant virus are found on the Greenland ice sheet. Microbiome 12, 91; doi: 10.1186/s40168-024-01796-y

Source: www.sci.news

Researchers warn that the rapid spread of a virus poses a threat to the health of cocoa trees

Cocoa swollen bud virus disease It is one of the most economically damaging cocoa tree diseases, accounting for almost 15-50% of crop losses in Ghana. This virus is transmitted when several species of mealybugs feed on cocoa plants.

A cacao tree with cacao fruit attached directly to the trunk or branches.Image credit: Gamera other., doi: 10.1094/PDIS-10-22-2412-FE.

Cocoa swollen shoot virus disease (CSSVD) first observed Infected by farmers in the eastern region of Ghana in 1936, the nature of the virus was identified in 1939.

CSSVD is considered the most economically damaging cocoa virus disease and can cause yield losses of 15-50% when severe strains are involved in infection.

Cocoa swollen shoot virus (CSSV) is classified as a member of the plant-infecting pararetroviruses of the genus Cocoa swollen shoot virus. badnavirus It contains nonenveloped rod-like particles that encapsulate a circular double-stranded DNA genome.

Previously, isolates and strains were grouped according to severity of symptom onset and geographic origin.

CSSVD is currently known to be caused by the following causes: complex of badnavirus seed Based on molecular structure.

CSSV affects all parts of the cocoa plant. Symptoms seen on leaves include red vein stripes on immature “flush” leaves, green-green vein spots or stripes that can occur in angular spots, removal of green-green veins, and various shapes Includes mosaic symptoms.

The virus causes swelling of the stem (nodes, internodes, tips) and roots.

In some strains, the infected pods change shape, becoming rounder and smaller and with a smoother surface.

“This virus is a real threat to the world's chocolate supply,” said Professor Benito Chen Charpentier, a researcher at the University of Texas at Arlington.

“Pesticides are ineffective against mealybugs, so farmers try to prevent the spread of the disease by cutting down infected trees or breeding resistant trees. However, Ghana has lost more than 254 million cocoa trees in recent years.

Farmers can combat mealybugs by vaccinating trees with CSSV. But vaccines are expensive, especially for low-wage farmers, and vaccinated trees produce less cocoa, making the damage caused by the virus even worse.

Electron micrograph of swollen shoot virus particles in purified cocoa. Scale bar – 200 nm.Image credit: Gamera other., doi: 10.1094/PDIS-10-22-2412-FE.

Professor Chen Charpentier and colleagues have developed a new strategy. Use mathematical data to determine how far apart farmers can plant vaccinated trees to prevent mealybugs from jumping from one tree to another and spreading the virus That's what it is.

“Mealybugs have several ways of getting around, including moving from canopy to canopy, being carried by ants, and being blown by the wind,” Professor Chen Charpentier said.

“What we needed to do was create a model for cocoa farmers to vaccinate unvaccinated trees to prevent the spread of the virus while making costs more manageable for smallholders. The goal was to be able to know how far away a tree could be safely planted.”

By experimenting with mathematical patterning techniques, the authors create two different types of models that allow farmers to create a protective layer of vaccinated cocoa trees around unvaccinated trees. Did.

“Although still experimental, these models are exciting because they can help farmers protect their crops while achieving better yields,” said Professor Chen Charpentier.

“It’s good for farmers’ bottom lines and it’s good for the world’s chocolate addiction.”

a paper The findings were published online in the journal PLoS ONE.

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FB Agusto other. 2024. Cocoa Sustainability: The Case of Cocoa Swollen Bud Virus Co-infection. PLoS ONE 19 (3): e0294579; doi: 10.1371/journal.pone.0294579

Source: www.sci.news