Sudan Ebola virus can persist in survivors for months

Image Credit: AI Generated

Scientific Frontline: Extended "At a Glance" Summary: Long-Term Sequelae of Sudan Ebolavirus

The Core Concept: More than half of Sudan ebolavirus survivors experience severe, ongoing health complications—a post-viral syndrome termed "long Ebola"—up to two years post-infection. Pathogenic viral RNA can persist in specific bodily secretions for several months after the resolution of acute clinical symptoms.

Key Distinction/Mechanism: Unlike prior longitudinal studies that primarily tracked the Zaire strain, this research explicitly isolates the long-term pathology of the Sudan strain. The virus utilizes "immune-privileged" sites (anatomical zones with restricted immune system access, such as the testes and mammary glands) to evade clearance, leading to viral latency, potential reactivation, and multi-systemic symptomatic damage.

Major Frameworks/Components:

• Comparative Methodology: Tracked 87 outbreak survivors alongside 176 uninfected community controls over a 24-month period (assessments at 3, 9, 12, 15, and 24 months).
• Viral Persistence: Documented viral RNA in semen for up to 210 days and in breast milk for up to 199 days.
• Systemic Sequelae: Identified high-frequency, persistent symptoms impacting the musculoskeletal system (45%), central nervous system (36%), and ocular system (20%).
• Latency and Reactivation: Observed viral reappearance in semen after consecutive negative tests, demonstrating ongoing biological latency eight months post-infection.

Vaccine candidates for Ebola

Axel Lehrer in his lab at the John A. Burns School of Medicine.
Photo Credit: University of Hawaiʻi

Scientific Frontline: Extended "At a Glance" Summary: Thermostable Filovirus Vaccines

The Core Concept: Researchers have successfully demonstrated the efficacy of multiple thermostable vaccine candidates targeting three deadly filoviruses—Ebola, Sudan, and Marburg—in non-human primates.

Key Distinction/Mechanism: Unlike traditional vaccines that require strict refrigeration (the cold chain), these vaccines are thermostabilized within single vials, allowing them to remain shelf-stable and viable in environments with uncertain or nonexistent power supplies.

Major Frameworks/Components:

• Multivalent Formulation: The ability to combine multiple antigens in a single formulation to generate broad protective immunity against distinct viral strains.
• Thermostabilization Platform: A specialized manufacturing process that produces heat-stable vaccines requiring no refrigeration or freezing.
• Adaptable Technology: A foundational vaccine platform currently being leveraged to develop stabilizing protocols for other pathogens, including SARS-CoV-2 (COVID-19).

Using plants to fight Ebola and COVID-19

Michel Chrétien, professor emeritus at the Faculty of Medicine, Université de Montréal.
Photo Credit: Amélie Philibert, Université de Montréal.

Scientific Frontline: Extended "At a Glance" Summary: Dicitriosides as Novel Antivirals

The Core Concept: Dicitriosides are newly identified triterpenoid compounds discovered in a plant extract that demonstrate potent, broad-spectrum antiviral activity against the Ebola virus and SARS-CoV-2. These rare natural molecules offer significant therapeutic potential at pharmacologically achievable concentrations.

Key Distinction/Mechanism: Previously, the antiviral effects of this plant extract were mistakenly attributed to isoquercitrin, a common flavonoid. Using advanced analytical methods, researchers pinpointed that these two obscure dicitriosides—comprising only 0.4% of the extract—were actually responsible for the activity and proved up to 25 times more effective than the original extract.

Major Frameworks/Components:

• Bioassay-Guided Isolation: A rigorous analytical approach used to trace and identify the microscopic amounts of active dicitriosides within a complex botanical mixture.
• Multilevel Residual Complexity Analysis: The methodological framework employed to reveal the origin of the nanomolar antiviral bioactives previously masked by 'isoquercitrin'.
• Triterpenoid Compounds: The specific chemical classification of the two newly discovered dicitriosides.

What Is: Ebola (Orthoebolavirus zairense)

Ebola virus (species Orthoebolavirus zairense).
Image Credit: CDC

Scientific Frontline: Extended "At a Glance" Summary: Orthoebolavirus zairense (Ebola Virus)

The Core Concept: Orthoebolavirus zairense is a highly sophisticated filovirus that relies on complex molecular evasion, the exploitation of immune-privileged sanctuaries, and the induction of societal disruption to ensure its survival and propagation, challenging its traditional, simplified classification as merely an agent of acute hemorrhagic fever.

Key Distinction/Mechanism: Unlike pathogens that trigger immediate immune clearance, this virus actively subverts the human immune system through RNA editing (overproducing the sGP protein to hijack antibody responses) and establishes long-term chronicity by physically breaking down cellular barriers to hide in the central nervous system, eyes, and testes.

Origin/History: The virus maintains a peaceful evolutionary truce within its natural chiropteran (bat) reservoir. Bats harbor the virus asymptomatically due to an evolutionary genomic mutation (S358) in their STING pathway, which dampens their inflammatory response to accommodate the severe metabolic demands of flight.

Marburg vaccine shows promising results in first-in-human study

Colorized scanning electron micrograph of Marburg virus particles (blue) both budding and attached to the surface of infected VERO E6 cells (orange).
Image Credit: National Institute of Allergy and Infectious Diseases

A newly published paper in The Lancet shows that an experimental vaccine against Marburg virus (MARV) was safe and induced an immune response in a small, first-in-human clinical trial. The vaccine, developed by researchers at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, could someday be an important tool to respond to Marburg virus outbreaks.

This first-in-human, Phase 1 study tested an experimental MARV vaccine candidate, known as cAd3-Marburg, which was developed at NIAID’s Vaccine Research Center (VRC). This vaccine uses a modified chimpanzee adenovirus called cAd3, which can no longer replicate or infect cells, and displays a glycoprotein found on the surface of MARV to induce immune responses against the virus. The cAd3 vaccine platform demonstrated a good safety profile in prior clinical trials when used in investigational Ebola virus and Sudan virus vaccines developed by the VRC.

Protect habitat to prevent pandemics

Photo Credit: Vlad Kutepov

Scientific Frontline: Extended "At a Glance" Summary: Habitat Conservation as Pandemic Prevention

The Core Concept: Habitat preservation serves as a critical public health strategy by maintaining ecological integrity, thereby preventing the zoonotic spillover of pathogens from wild animal populations to humans.

Key Distinction/Mechanism: Unlike reactive medical responses that address outbreaks after they occur, this approach functions as a preemptive bio-containment strategy by reducing animal stress levels and minimizing physical contact between human populations and displaced wildlife.

Origin/History: This concept gained significant scientific traction in the early 21st century following the increased frequency of zoonotic disease emergence (such as SARS, Ebola, and COVID-19), which researchers have linked to anthropogenic land-use changes and habitat fragmentation.

Vaccine printer could help vaccines reach more people

MIT researchers have designed a mobile vaccine printer that could be scaled up to produce hundreds of vaccine doses in a day. This kind of printer, which can fit on a tabletop, could be deployed anywhere vaccines are needed. Pictured is an artist’s interpretation of the printer.
Illustration Credit: Ryan Allen from Second Bay Studios
(CC BY-NC-ND 3.0)

Getting vaccines to people who need them isn’t always easy. Many vaccines require cold storage, making it difficult to ship them to remote areas that don’t have the necessary infrastructure.

MIT researchers have come up with a possible solution to this problem: a mobile vaccine printer that could be scaled up to produce hundreds of vaccine doses in a day. This kind of printer, which can fit on a tabletop, could be deployed anywhere vaccines are needed, the researchers say.

“We could someday have on-demand vaccine production,” says Ana Jaklenec, a research scientist at MIT’s Koch Institute for Integrative Cancer Research. “If, for example, there was an Ebola outbreak in a particular region, one could ship a few of these printers there and vaccinate the people in that location.”

The printer produces patches with hundreds of microneedles containing vaccine. The patch can be attached to the skin, allowing the vaccine to dissolve without the need for a traditional injection. Once printed, the vaccine patches can be stored for months at room temperature.

Harmful Effects of Long-Term Alcohol Use Documented in Blood Protein Snapshot

Jon Jacobs recently found that a particular combination of blood proteins indicates alcohol-associated hepatitis, a deadly liver disease. 
Photo Credit: Eddie Pablo III | Pacific Northwest National Laboratory

Biochemist Jon Jacobs has analyzed the blood of patients with diseases and conditions such as Ebola, cancer, tuberculosis, hepatitis, diabetes, Lyme disease, brain injury and influenza.

But never has he seen blood chemistry gone so awry as when he and colleagues took an in-depth look at the protein activity in the blood of patients with alcohol-associated hepatitis, a severe form of liver disease caused by heavy drinking for many years.

“The proteins in these patients are more dysregulated than in any other blood plasma that we’ve analyzed,” said Jacobs, a scientist at the Department of Energy’s Pacific Northwest National Laboratory. “Almost two-thirds of the proteins we measured are at unusual levels. This is a snapshot of what’s going on in the body of a person with this disease and reflects just how severe a disease this is.”

That “snapshot” is a measurement of proteins that change in patients with the disease. The unique combination of changes in protein activity marks an important step toward development of a simple blood test to diagnose alcohol-associated hepatitis.

Jacobs and colleagues, including scientists and physicians from the Veteran Affairs Long Beach Healthcare System and the University of Pittsburgh, published their findings recently in the American Journal of Pathology. Corresponding authors of the study are Jacobs and Timothy Morgan, a gastroenterologist at VA Long Beach who has treated patients with the disease for more than 35 years.

Virology: In-Depth Description

Image Credit: Scientific Frontline / AI generated

Virology is the branch of biological science dedicated to the study of viruses—submicroscopic, parasitic particles of genetic material contained in a protein coat—and virus-like agents. Its primary goal is to understand the structure, classification, and evolution of these pathogens, their mechanisms of infection and exploitation of host cells, and their interactions with host organism physiology and immunity.

Research Finds Repurposed Drug Inhibits Enzyme Related to COVID-19

With the end of the pandemic seemingly nowhere in sight, scientists are still very focused on finding new or alternative drugs to treat and stop the spread of COVID-19. In a first-of-its-kind study, researchers at the University of New Hampshire have found that using an already existing drug compound in a new way, known as drug repurposing, could be successful in blocking the activity of a key enzyme of the coronavirus, or SARS-CoV-2, which causes COVID-19.

“The goal was to slow or prevent the spread of the virus by using a strategic therapeutic that could possibly disrupt key steps in the viral life cycle at the molecular level, like the first contact with a healthy cell or the first step in replicating within an infected cell,” said Harish Vashisth, associate professor of chemical engineering.

In their study, recently published in the journal PROTEINS: Structure, Function, and Bioinformatics, researchers set out to target a key enzyme responsible for COVID-19, called the main protease enzyme Mpro, which has become a primary target of intense research and therapeutic development because it is essential for the virus to replicate. In this case, they explored the inhibiting properties of a derivative of the potent chemical compound known as Thiadiazolidinones, or TDZD, which are already being studied as a potential treatment for neurological disorders like Parkinson’s Disease. Researchers used a specific TDZD compound, known as CCG-50014, to target Mpro which acts like a molecular scissor by cutting up long chains of polypeptide proteins of the virus into smaller component proteins. These smaller segments can fold and mature to form new virus particles. Using molecular dynamics simulations combined with laboratory experiments, the researchers determined that TDZD compound was able to inhibit the Mpro enzyme.

Anti-cancer drug derived from fungus shows promise in clinical trials

An image of the fungus Cordyceps sinensis. This fungus grows naturally on caterpillars at high altitudes in the Himalayas.

A new industry-academic partnership between the University of Oxford and biopharmaceutical company NuCana as found that chemotherapy drug NUC-7738, derived from a Himalayan fungus, has 40 times greater potency for killing cancer cells than its parent compound.

Oxford University researchers have worked in collaboration with industry leaders NuCana to assess a novel chemotherapy drug derived from a fungus. A study in Clinical Cancer Research has shown that the new drug NUC-7738, developed by NuCana, has a up to 40 times greater potency for killing cancer cells than its parent compound, with limited toxic side effects.

The naturally-occurring nucleoside analogue known as Cordycepin (a.k.a 3’-deoxyadenosine) is found in the Himalayan fungus Cordyceps sinensis and has been used in traditional Chinese medicine for hundreds of years to treat cancers and other inflammatory diseases. However, it breaks down quickly in the blood stream, so a minimal amount of cancer-destroying drug is delivered to the tumor. In order to improve its potency and clinically assess its applications as a cancer drug, biopharmaceutical company NuCana has developed Cordycepin into a clinical therapy, using their novel ProTide technology, to create a chemotherapy drug with dramatically improved efficacy.

Zoology: In-Depth Description

Image Credit: Scientific Frontline / AI generated (Gemini)

Zoology is the branch of biology dedicated to the scientific study of the animal kingdom, encompassing the structure, embryology, evolution, classification, habits, and distribution of all living and extinct animals. As a discipline, it seeks to understand how animals interact with their ecosystems, how they function physiologically, and how they have adapted to diverse environments over millions of years.

Influenza A viruses adapt shape in response to environmental pressures

Colorized transmission electron micrograph of influenza A virus particles, colorized red and gold, isolated from a patient sample and then propagated in cell culture. Influenza A can infect both humans and animals, including birds and pigs. More specifically, this image features the H3N2 influenza strain, isolated from a patient in Victoria, Australia, in 1975. Notable for forming both spheric
Image Credit: National Institute of Allergy and Infectious Diseases

Influenza A virus particles strategically adapt their shape—to become either spheres or larger filaments—to favor their ability to infect cells depending on environmental conditions, according to a new study from National Institutes of Health (NIH) scientists. This previously unrecognized response could help explain how influenza A and other viruses persist in populations, evade immune responses, and acquire adaptive mutations, the researchers explain in a new study published in Nature Microbiology.

The study, led by intramural researchers at NIH’s National Institute of Allergy and Infectious Diseases (NIAID), was designed to determine why many influenza A virus particles exist as filaments. The filament shape requires more energy to form than a sphere, they state, and its abundance has been previously unexplained. To find the answer, they developed a way to observe and measure real-time influenza A virus structure during formation.

How a CRISPR Protein Might Yield New Tests for Many Viruses

In this illustration based on cryo-electron microscope images, a Cas12a2 protein unzips a DNA double helix, allowing it to cut the single strands of DNA (blue and green).
Illustration Credit: Jack Bravo/University of Texas at Austin

In a first for the genetic toolset known as CRISPR, a recently discovered protein has been found to act as a kind of multipurpose self-destruct system for bacteria, capable of degrading single-stranded RNA, single-stranded DNA and double-stranded DNA. With its abilities to target so many types of genetic material, the discovery holds potential for the development of new inexpensive and highly sensitive at-home diagnostic tests for a wide range of infectious diseases, including COVID-19, influenza, Ebola and Zika, according to the authors of a new study in the journal Nature.

Using a high-resolution imaging technique called cryo-EM, the team discovered that when this protein, named Cas12a2, binds to a specific sequence of genetic material from a potentially dangerous virus, called a target RNA, a side portion of Cas12a2 swings out to reveal an active site, similar to a sprung-open switchblade knife. Then, the active site starts to indiscriminately cut any genetic material it comes into contact with. The researchers discovered that, with a single mutation to the Cas12a2 protein, the active site degrades only single-stranded DNA—a feature especially useful in developing new diagnostics tailored for any of a wide range of viruses.

Discovery of antibody structure could lead to treatment for Crimean Congo Hemorrhagic Fever virus

Scott D. Pegan, a professor of biomedical sciences
Photo Source: University of California, Riverside

A research team led by the University of California, Riverside, has discovered important details about how therapeutically relevant human monoclonal antibodies can protect against Crimean Congo Hemorrhagic Fever virus, or CCHFV. Their work, which appears online in the journal Nature Communications, could lead to the development of targeted therapeutics for infected patients.

An emerging zoonotic disease with a propensity to spread, CCHF is considered a priority pathogen by the World Health Organization, or WHO. CCHF outbreaks have a mortality rate of up to 40%. Originally described in Crimea in 1944–1945, and decades later in the Congo, the virus has recently spread to Western Europe through ticks carried by migratory birds. The disease is already endemic in Africa, the Balkans, the Middle East, and some Asian countries. CCHFV is designated as a biosafety level 4 pathogen (the highest level of biocontainment) and is a Category A bioterrorism/biological warfare agent. There is no vaccine to help prevent infection and therapeutics are lacking.

Scott D. Pegan, a professor of biomedical sciences in the UCR School of Medicine, collaborated on this study with the United States Army Medical Research Institute of Infectious Diseases, or USAMRIID, which studies CCHFV because of the threat it poses to military personnel around the world. They examined monoclonal antibodies, or mAbs, which are proteins that bind to antigens — foreign substances that enter the body and cause the immune system to mount a protective response.

In a previous publication, USAMRIID scientists Joseph W. Golden and Aura R. Garrison reported that an antibody called 13G8 protected mice from lethal CCHFV when administered post-infection. They provided Pegan with the sequence information for that antibody, clearing the way for UCR to “humanize” it and conduct further research.

To prevent next pandemic research suggests we need to restore wildlife habit

Researchers found that bats disrupted by a lack of habitat and food move near humans in agricultural and urban areas, where they can spread Hendra virus to horses and then people.
Photo Credit: Vlad Kutepov

Preserving and restoring natural habitats in specific locations could prevent pathogens that originate in wildlife from spilling over into domesticated animals and humans, according to new research led by an international team of researchers, including Penn State.

The research, undertaken in Australia, found that when bats experience a loss of winter habitat and food shortages in their natural settings, their populations splinter and they excrete more virus. Bats disrupted by the lack of food move near humans in agricultural and urban areas. The team studied Hendra virus, a lethal virus that spills over from fruit bats to horses and then infects people.

“One of the biggest challenges we face are threats arising from bat-borne viruses that spillover into humans and have the potential to cause pandemics. Ebola, MERS, SARS, SARS-CoV-2, Nipah and Hendra are all good examples of this,” said Peter Hudson, Willaman Professor of Biology, Penn State. “The response to the pandemic has been to find ways to speed up vaccine development, but since infections invariably spread much faster than vaccine rollout, this reactive response will never stop a pandemic. Instead, the solution lies with preventing viral spillover from bats to humans.”

Seeking COVID’s Kryptonite

Photos of the setup. Left: A closeup of the interior of the box containing the laser-to-fiber-optic coupling system. Center: The laser system in the hallway outside the door to BSL-3. Right: A closeup of the experimental setup inside BSL-3, including the chamber the housed the samples of SARS-CoV-2.
 Credit: NIST

To disinfect a surface, you can illuminate it with a blast of ultraviolet (UV) light, which is bluer than the human eye can see. But to specifically inactivate SARS-CoV-2, the virus that causes COVID-19, which wavelengths are best? And how much radiation is enough?

Answering those questions requires scientists to overcome two main obstacles. First, they need to separate the virus completely from extraneous substances in the environment. Second, they need to illuminate the virus with a single wavelength of UV light at a time, with minimal changes to the experimental setup between tests.

A recent collaboration between the National Institute of Standards and Technology (NIST) and the National Biodefense Analysis and Countermeasures Center (NBACC), a U.S. Department of Homeland Security Science and Technology Directorate laboratory, overcame both these obstacles and completed what may be the most thorough test ever conducted of how several different UV and visible wavelengths affect SARS-CoV-2.

In a new paper published this week in Applied Optics, the collaborators describe their novel system for projecting a single wavelength of light at a time onto a sample of COVID-19 virus in a secure laboratory. Classified as Biosafety Level 3 (BSL-3), the lab is designed for studying microbes that are potentially lethal when inhaled. Their experiment tested more wavelengths of UV and visible light than any other study with the virus that causes COVID-19 to date.

Epidemiology: In-Depth Description

Epidemiology is the fundamental science of public health, defined as the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems. Its primary goals are to identify the etiology (cause) of diseases, determine the extent of disease burden in communities, study the natural history and prognosis of diseases, and evaluate preventive and therapeutic measures.

What Is: Zoonotic Spillover

Scientific Frontline: Extended "At a Glance" Summary: Zoonotic Spillover

The Core Concept: Zoonotic spillover is the successful transmission of a pathogenic entity—such as a virus, bacterium, or parasite—from a non-human animal reservoir into a human population. This rare but consequential event occurs when a pathogen successfully crosses the strict biological boundary between species.

Key Distinction/Mechanism: Unlike regular endemic transmission, a zoonotic spillover is dictated by the "Spillover Barrier Model." A pathogen must overcome a hierarchical series of formidable biological and ecological obstacles. Spillover only succeeds when specific vulnerabilities across these barriers perfectly align in both space and time, allowing the pathogen to bind to human cellular receptors and evade immediate immune destruction.

Major Frameworks/Components:

• The Three Layers of Biological Barriers: The zoonotic reservoir layer (host density and distribution), the environmental and vector layer (pathogen persistence in abiotic conditions), and the recipient spillover host layer (human exposure, susceptibility, and cellular infection dynamics).
• Viral Shedding Dynamics: Pathogens are often excreted in discrete temporal and spatial "pulses" triggered by demographic shifts or environmental stress.
• Epidemiological Transmission Models:
• SIR (Susceptible-Infectious-Recovered): Seasonal epidemic cycles driven by natural host population fluctuations.
• SIRS (Susceptible-Infectious-Recovered-Susceptible): Cyclical circulation driven by waning immunity within a reservoir.
• SILI (Susceptible-Infectious-Latent-Infectious): Persistent infections triggered by stress-induced viral reactivation.

What Is: The Virome

Scientific Frontline: Extended "At a Glance" Summary: The Virome

The Core Concept: The virome refers to the vast, complex, and heterogeneous collection of all viruses that are found in or on an organism, or within a specific environmental ecosystem.

Key Distinction/Mechanism: Historically relegated to the domain of clinical pathology and infectious disease, viruses are now understood to be the most abundant and influential biological entities on Earth, serving as architects of human physiology and ultimate regulators of global biogeochemical cycles. Rather than exclusively causing overt clinical disease, commensal viruses establish long-term, asymptomatic, and mutualistic relationships that act as continuous, low-level stimulants to the host's immune system, revealing a trans-kingdom functional redundancy that challenges the bacterial-centric view of the microbiome.

Major Frameworks/Components:

• Eukaryotic Viruses: These agents establish persistent or latent infections that constantly shape the host's immunophenotype, conferring basal levels of innate resistance against novel external pathogens.
• Bacteriophages: Functioning as the apex predators of the microscopic world, phages exclusively infect bacteria to rigorously regulate bacterial population density, mediate the horizontal transfer of genetic material, and form protective antimicrobial layers on mucosal surfaces.
• Archaeal Viruses: These distinct entities specifically infect the archaeal domain, deeply influencing archaeal population dynamics and participating in metabolic regulation within complex ecological niches like the deep gastrointestinal tract.
• Endogenous Retroviruses (HERVs): These ancient viral sequences retain potent regulatory functions and have been domesticated for critical life-sustaining processes, such as mammalian placentation via the syncytin protein. Conversely, the aberrant expression of these ancient viral elements is now heavily implicated in severe, progressive neurodegenerative diseases such as Multiple Sclerosis (MS) and Amyotrophic Lateral Sclerosis (ALS).