Sunday, November 23, 2025

A fast, lasting defense against a deadly virus

Scientists create a vaccine that shields against Crimean-Congo hemorrhagic fever within days and protects for over a year

University of California - Riverside

RIVERSIDE, Calif. -- Crimean-Congo hemorrhagic fever (CCHF) is one of the world’s most dangerous yet overlooked infectious diseases. Spread by ticks and livestock, the virus causes sudden fever, organ failure, and internal bleeding, killing up to 40% of those infected. Outbreaks have been reported across parts of Africa, Asia, Eastern Europe, and the Middle East. Despite decades of research, no approved vaccines or treatments exist.

Now, a mouse study, published in the journal npj Vaccines, brings fresh optimism. A research team, including biomedical scientist Scott Pegan at the University of California, Riverside, has developed a vaccine made from a non-infectious version of the CCHF virus that protects quickly and provides long-lasting immunity.

Previous research by the team had shown that this experimental vaccine could protect animals within just three days after a single dose — unusually fast for any vaccine. The new study now reports that the protection is durable as well.

The researchers tested how long the immune response lasted in mice after one or two doses. They found that antibodies remained detectable for up to 18 months — roughly equivalent to several years in humans. Antibody levels were similar between the one- and two-dose groups for about nine months, but animals that received a booster developed stronger, more stable antibodies that offered better and longer-lasting protection.

According to Pegan, creating a vaccine for CCHF has been notoriously difficult.

“CCHF is one of those viruses where you can’t simply use the outer coat proteins to make a vaccine,” said Pegan, a professor of biomedical sciences in the UCR School of Medicine.

Instead, the team took a different route. Their vaccine uses what’s known as a virus-like replicon particle — something that looks and behaves like the real virus but is completely harmless.

“Made in the lab, this particle can enter cells like a normal virus, but it doesn’t have the genetic material to replicate,” Pegan said. “That allows the immune system to respond to the virus-like particle without any risk of infection.”

What makes this vaccine stand out is the part of the CCHF virus it targets, Pegan explained. He said most vaccines train the immune system to recognize proteins on the virus’s surface, but this one focuses on internal proteins — particularly a component called the N protein.

“Our earlier work showed that the N protein, which is usually hidden inside the virus, turns out to be the key to protective immunity,” he said.

This unconventional strategy also explains why the vaccine works so quickly, Pegan said.

“We were amazed to see antibodies appear within just a few days,” he added. “The rapid response is one reason this platform is succeeding where others haven’t.”

The new findings on long-term protection add to the growing promise of the CCHF vaccine. A single dose appears strong enough for meaningful protection, while a booster helps keep immunity steady for even longer.

“That could be crucial for outbreak regions where people might not have easy access to follow-up vaccinations,” Pegan said.

Next, the research team plans to move toward large-scale production under Good Manufacturing Practice (GMP) standards, a key step before human clinical trials can begin.

“We can make the vaccine in the lab right now, but GMP ensures it can be produced safely, consistently, and at scale,” Pegan said.

Beyond CCHF, the same technology could help tackle other dangerous viruses.

“Our partners at the Centers for Disease Control and Prevention are already exploring this platform for diseases like Nipah virus,” Pegan said. “It’s a flexible system that could be adapted for a range of emerging pathogens.”

Ultimately, the team believes this vaccine could make a difference — especially for communities and health workers in regions where CCHF is endemic.

“Having something that can protect quickly and last a long time could save lives and change how we respond to outbreaks,” Pegan said.

Pegan was joined in the study by scientists at the Centers for Disease Control and Prevention (CDC), U.S. Department of Agriculture, and Auburn University in Alabama.

The research was supported in part by the CDC and the National Institute of Allergy and Infectious Diseases of the National Institutes of Health. The findings and conclusions do not necessarily represent the official position of the CDC.

The title of the paper is “Durable humoral immunity and long-term protection induced by a Crimean-Congo hemorrhagic fever virus replicon particle vaccine in mice.”

The University of California, Riverside is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment is more than 26,000 students. The campus opened a medical school in 2013 and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Center. The campus has an annual impact of more than $2.7 billion on the U.S. economy. To learn more, visit www.ucr.edu.

Journal

npj Vaccines

DOI

10.1038/s41541-025-01293-9

Method of Research

Experimental study

Subject of Research

Animals

Article Title

Durable humoral immunity and long-term protection induced by a Crimean-Congo hemorrhagic fever virus replicon particle vaccine in mice

Article Publication Date

21-Nov-2025

NJIT scientists track recent solar flare disruptions in Earth’s ionosphere

New Jersey Institute of Technology

All-Day Solar Radio Spectrograms Under Normal Ionosphere Conditions vs. X1.7 Solar Flare Aftermath — image:
OVRO-LWA radio data contrasts a quiet day (Sept. 29, 2025) with the hours after the X1.7-class flare recorded at 2:35 ET on Nov. 9. The type III radio bursts, shown in the radio dynamic spectrum (horizontal axis is UT time, vertical axis is frequency), appear nearly vertical bursts during stable ionospheric conditions. After flare-driven X-ray and UV radiation ionized the lower ionosphere and geomagnetic storms driven by the associated coronal mass ejections, these radio bursts became curved and chaotic, particularly at low frequencies (bottom of the plot).
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Credit: NJIT/OVSA Team

As this month’s string of powerful X-class solar flares sparked brilliant aurorae that lit up skies across an unusually wide swath of the globe — from northern Europe to Florida — researchers at NJIT’s Center for Solar-Terrestrial Research (CSTR) captured a less visible, but crucial, record of the storm’s impact on Earth’s upper atmosphere.

Recent measurements recorded by NJIT’s new network of radio telescopes show how a rare sequence of intense flares from Nov. 9–14, including an X5.1 event marking 2025’s strongest flare so far, jolted the ionosphere — the plasma-filled atmospheric layer essential for radio signals, GPS accuracy and satellite orbits.

The flares triggered R3 (strong) radio blackouts across Africa and Europe, with several coronal mass ejections (CMEs) fueling a major geomagnetic storm and aurora at unusually low latitudes.

The cluster of explosive events originated from a single active region on the Sun, AR4274.

“It’s somewhat unusual to see four X-class flares in just a few days from the same region,” said Bin Chen, NJIT-CSTR professor of physics and director of the Expanded Owens Valley Solar Array (EOVSA). “An X1.7 flare on Nov. 9, an X1.2 on Nov. 10, an X5.1 on Nov. 11 and an X4.0 on Nov. 14 — that’s a very productive stretch. What really stood out were the ripple effects right here on Earth.”

Though the flares occurred during nighttime in California — out of view of NJIT’s Big Bear Solar Observatory — the center’s radio telescopes at the Owens Valley site in the Eastern Sierra recorded the flares’ aftermath and their disturbances in real time.

EOVSA and the newly operational Long Wavelength Array at Owens Valley Radio Observatory (OVRO-LWA) tracked dramatic atmospheric changes across a broad range of radio frequencies — from microwaves observed by EOVSA (similar to those used in satellite communications and Wi-Fi) down to the meter- and decameter waves captured by OVRO-LWA (similar to FM radio frequencies).

“Normally, OVRO-LWA radio data often show neat, nearly vertical bursts known as type III radio bursts,” said Chen. “After these flares, these bursts are curved and chaotic at low frequencies — a clear sign the ionosphere had been disturbed.”

For ionospheric scientists, the event was nearly as striking as the aurora.

“This storm was an excellent reminder that Earth is part of a much larger cosmic system,” said Lindsay Goodwin, NJIT-CSTR assistant professor of physics and ionosphere expert. “Not all extreme solar activity leads to a geomagnetic storm — sometimes the material misses Earth. But in this case, it hit.”

The result was a G4 geomagnetic storm on NOAA’s five-point scale.

“The Dst index, which measures how much Earth’s magnetic field is compressed by the solar wind, plunged from about –40 nT to nearly –250 nT in just a few hours,” Goodwin said. “That’s a huge shock to our planet’s magnetic defenses.”

Charged particles raining into the atmosphere produced auroras, and this event was extreme enough to push aurora far beyond their usual range, with sightings reported as far south as Florida.

“My aurora chat group was exploding with images from places that almost never see northern lights,” Goodwin said.

The episode also demonstrated the growing capability of NJIT’s radio observatories. OVRO-LWA recently entered full solar-science operations, opening a new window into the Sun’s “middle corona” — a region from about 1.5–10 solar radii where magnetic fields restructure and CMEs accelerate.

Supported by a $4.2 million National Science Foundation award, OVRO-LWA and EOVSA now operate together as an integrated community radio facility dedicated to solar and space weather research, referred to as the Owens Valley Solar Arrays (OVSA).

“This dataset is new by itself,” said Chen. “OVRO-LWA complements EOVSA perfectly. Together, they let us follow space-weather effects from their origin in the solar corona all the way to their impact on Earth’s upper atmosphere.”

Goodwin’s team, with help from NJIT undergrad Jeremy McLynch, recently added another dimension to the analysis.

Over the summer, their team deployed a high-precision GPS receiver beside the OVRO-LWA — nicknamed FLUMPH (Field-deployed L-band Unit for Monitoring Phase Hiccups), after the popular Dungeons & Dragons creature it resembles.

The device captures real-world disruptions to satellite-navigation signals during solar storms.

“Plasma irregularities caused by solar and geomagnetic activity disrupt radio and GPS communication,” Goodwin said. “Pairing GPS measurements with the LWA data lets us see both sides of the story — how the Sun shakes the ionosphere, and how that affects the technologies we rely on daily.”

For now, both Chen and Goodwin say the space weather research community is still unpacking the storm’s full impact. With the Sun near the peak of its 11-year activity cycle, Goodwin says similar storms are possible near-term.

“Scientists are only beginning to understand the full effects of this storm,” Goodwin said. “Historically, extreme solar and geomagnetic events can disrupt power grids, interfere with radio communications, and threaten the safety and operation of satellites and spacecraft. We’ve seen several major storms recently, because the Sun is still near the peak of its 11-year cycle.

“Such events will become less common as the Sun quiets down, but they will return in roughly 11 years — and when they do, understanding them will be even more important as we rely more on space technology and venture farther into space.”

Current heart attack screening tools are not optimal and fail to identify half the people who are at risk

The Mount Sinai Hospital / Mount Sinai School of Medicine

Distribution of risk categories and symptom timing — image:
Panel (A) shows classifications based on the ASCVD Risk Estimator Plus, where 45% (209/465) of patients would not have qualified for statin therapy or further testing. Panel (B) displays results from the PREVENT calculator, which classified an even larger proportion—61% (285/465)—as low or borderline risk despite subsequent MI. Panel (C) shows timing of symptom onset, with 279 patients (60%) developing symptoms within 48 hours of presentation.
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Credit: Mount Sinai Health System

Current cardiac screening tools used to prevent heart attacks fail to identify nearly half of the people who are actually at risk of having one, according to a new study led by Mount Sinai researchers. The results, published in a brief report on November 21, in the Journal of the American College of Cardiology: Advances, expose a major flaw in patient care: that following current screening guidelines may cause missed opportunities for early detection of heart attacks and prevention.

The researchers assessed the accuracy of a widely used tool, the atherosclerotic cardiovascular disease (ASCVD) risk score, and of a newer measure, called PREVENT, which adds variables and is intended to provide a more comprehensive estimate of cardiovascular risk along with symptomatic screening .

“Our research shows that population-based risk tools often fail to reflect the true risk for many individual patients,” says corresponding author Amir Ahmadi, MD, Clinical Associate Professor of Medicine (Cardiology) at the Icahn School of Medicine at Mount Sinai. “If we had seen these patients just two days before their heart attack, nearly half would NOT have been recommended for further testing or preventive therapy guided by current risk estimate scores and guidelines.

"This study suggests that the current approach of relying on risk scores and symptoms as primary gatekeepers for prevention is not optimal,” Dr. Ahmadi continued. “It may be time to fundamentally reconsider this model and move toward atherosclerosis imaging to identify the silent plaque – early atherosclerosis- before it has a chance to rupture.”

In current practice, doctors calculate a patient’s ASCVD risk score during annual primary care visits. This is typically done for people between 40 and 75 years old without known heart disease. This score estimates a person’s 10-year risk of having a heart attack or stroke using factors such as age, sex, race, blood pressure, cholesterol, diabetes, and smoking status. Physicians use the ASCVD or PREVENT calculators to guide decisions about preventive treatment, including whether to start statin therapy.

Cardiologists also rely on these same risk calculators as a guideline. Patients with intermediate or high scores are typically prescribed cholesterol-lowering medication and may be referred for additional testing. Those with low or borderline scores, especially if they have no symptoms like chest pain or shortness of breath, are often reassured and sent home without further evaluation. However, this study found that if patients who had their first heart attack had been evaluated two days earlier, nearly half of them would have been labeled as low or borderline risk and not recommended for preventive therapy by ASCVD, and more than half of them would have been so labeled by PREVENT.

To assess the effectiveness of current screening tools, researchers did a retrospective analysis on data from 474 patients under age 66 with no known coronary artery disease. All patients were treated for their first heart attack at Mount Sinai Morningside and The Mount Sinai Hospital in New York City between January 2020 and July 2025. The team collected personal information including patient demographics, medical history, cholesterol levels, blood pressure, and when their symptoms, defined as chest pain or shortness of breath, first appeared. For each patient, the 10-year ASCVD risk was calculated and a simulated assessment was performed as if the patient had been evaluated two days before their heart attack. Patients were divided into four risk groups: low (under 5 percent), borderline (5-7.5 percent), intermediate (7.5-20 percent) and high (more than 20 percent).

The results focused on two main factors: who would have qualified for preventive treatment based on their risk score, and when symptoms began. Overall, 45 percent of patients would not have been recommended for preventive therapy or diagnostic testing under current ASCVD-based guidelines, and this number increased to 61 percent when using the newer PREVENT calculator. Most patients (60 percent) did not develop symptoms such as chest pain or shortness of breath until less than two days before their cardiac event, showing that symptoms often appear too late to help with changing the course of disease. Together, these findings reveal a critical gap in current prevention strategies: patients who appear healthy by standard measures may already have significant, silent heart disease. Relying solely on risk scores and symptoms delays diagnosis until it is too late for prevention.

“When we look at heart attacks and trace them backwards, most heart attacks occur in patients in the low or intermediate risk groups. This study highlights that a lower risk score, along with not having classic heart attack symptoms like chest pain or shortness of breath, which is common, is no guarantee of safety on an individual level,” says first author Anna Mueller, MD, an internal medicine resident at the Icahn School of Medicine at Mount Sinai. “Our study exposes a major flaw where tools effective for tracking large populations fall short when guiding individualized care. Instead, doctors should shift their focus from detecting symptomatic heart disease to detecting the plaque itself for earlier treatment, which could save lives.”

Researchers say more studies are needed to further this work, and future research should focus on optimizing strategies to enhance early detection and prevention including cardiovascular imaging.

Mount Sinai Is a World Leader in Cardiology and Heart Surgery

Mount Sinai Fuster Heart Hospital at The Mount Sinai Hospital ranks No. 2 nationally for cardiology, heart, and vascular surgery, according to U.S. News & World Report®. It also ranks No. 1 in New York and No. 6 globally according to Newsweek’s “The World’s Best Specialized Hospitals.”

It is part of Mount Sinai Health System, which is New York City's largest academic medical system, encompassing seven hospitals, a leading medical school, and a vast network of ambulatory practices throughout the greater New York region. We advance medicine and health through unrivaled education and translational research and discovery to deliver care that is the safest, highest-quality, most accessible and equitable, and the best value of any health system in the nation. The Health System includes approximately 9,000 primary and specialty care physicians; 10 free-standing joint-venture centers throughout the five boroughs of New York City, Westchester, Long Island, and Florida; and 48 multidisciplinary research, educational, and clinical institutes. Hospitals within the Health System are consistently ranked by Newsweek’s® “The World’s Best Smart Hospitals” and by U.S. News & World Report's® “Best Hospitals” and “Best Children’s Hospitals.” The Mount Sinai Hospital is on the U.S. News & World Report's® “Best Hospitals” Honor Roll for 2025-2026.

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