Between 1 January and 5 October 2026, the Kingdom of Saudi Arabia reported eight laboratory-confirmed cases of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infection, including one death. Infection was confirmed by RT-PCR testing.

All eight cases were symptomatic, most commonly presenting with fever (6/8), dyspnea/shortness of breath (5/8), and cough (4/8). None were health and care workers.

Of the eight reported cases, five occurred among persons aged 70 years and older, two among adults aged 50–59 years, and one among an adult aged 30–39 years. The death was reported in an older adult (>65 year old) with comorbidities.

There was no known epidemiological link identified among cases.

MERS is a zoonotic viral respiratory disease for which dromedary camels serve as the primary animal reservoir and two cases reported direct contact with camels while six reported no known camel exposure. Seven of eight cases had underlying comorbidities, recognized risk factors for severe MERS-CoV disease.

The cases appear to represent sporadic infections related to zoonotic spillover rather than a single outbreak cluster.

[...]

Epidemiology

Middle East respiratory syndrome (MERS) is a respiratory illness caused by a coronavirus (MERS-CoV). The fatality rate among confirmed cases is around 36%, though this may be an overestimate since milder cases often go undetected. The CFR is calculated based solely on laboratory-confirmed infections, which may not reflect the correct mortality rate.

Humans contract MERS-CoV through direct or indirect contact with dromedary camels, the virus’s natural host and zoonotic reservoir. Human-to-human transmission is possible and occurs predominantly among close contacts (family and household members) and in health-care settings (health-care workers and among patients). The largest outbreaks occurred in health-care facilities in the Republic of Korea, Saudi Arabia, and the United Arab Emirates. Outside these environments, there has been limited documented human-to-human transmission to date.

MERS can present with no symptoms, mild respiratory issues, or severe illness leading to acute respiratory distress and death. Common symptoms include fever, cough, and breathing difficulties, with pneumonia frequently observed, though not always present. Some patients also experience gastrointestinal symptoms such as diarrhoea. Severe cases may require intensive care, including mechanical ventilation. Those at higher risk of severe outcomes include older adults, individuals with weakened immune systems, and those with chronic conditions like diabetes, kidney disease, cancer, or lung disorders.

No vaccine or specific treatment is currently available, although several MERS-CoV-specific vaccines and therapeutics are in development. Treatment remains supportive, focusing on managing symptoms based on the severity of the illness.

[...]

Ebola Bundibugyo virus on Saturday, including three health workers who treated the country's first patient, bringing the ​total number of confirmed cases to seven, the health ministry said.

The other ‌new case is a male relative of the index patient, who died. The relative had been in quarantine since October 6, the ministry said in a statement.

The cases are the first known infections passed ​on inside Kenya, where the first patient arrived from Congo on October 3. ​But the ministry says it has traced and quarantined nearly all of ⁠his contacts and there is no evidence that the virus is spreading in the ​community.

The three health workers — two men and a woman aged 29, 35 and 32 respectively — ​managed the index case on October 3 and 4 and had been in quarantine since October 9, it said. All four new patients were already in quarantine when they developed symptoms and were diagnosed.

The ​second and third patients confirmed earlier are stable and responding well to supportive treatment, the ​ministry said. It said 128 of 130 listed contacts, or 98.5%, had been traced and placed in ‌quarantine, ⁠higher than the 85% global benchmark it said was needed to break the chain of transmission.

Kenya's cases are linked to the Ebola epidemic in Congo — the second-largest outbreak ever recorded, with more than 9,000 cases and more than 4,000 deaths. [...]

A third person in Kenya has tested positive for Ebola, health ministry officials announced, according to Africa News. The 65-year-old woman—a close relative of the first two Ebola cases in the country—started quarantining prior to developing symptoms.

Yesterday, health officials reported that two cases of Ebola has been detected in an eighth province, North Ubangi. According to Reuters, the DRC has yet to officially announce the infections.

Ituri province has seen the most Ebola cases, with North Kivu province recently experiencing a spike in cases. South Kivu, Tshopo, Haut-Uele, Bas-Uele, and South Ubangi provinces have also reported Ebola cases during this outbreak. So far, the virus has sickened 9,235 people and led to 4,444 deaths, according to the US Centers for Disease Control and Prevention (CDC).

Children in the Democratic Republic of Congo (DRC) have been in school for only a little more than a month, yet 10 students have already died of the Bundibugyo Ebola virus, per Africa News.

Twenty-five Ebola cases have been confirmed in schoolchildren in Ituri, with seven survivors still undergoing treatment. Early this month, the humanitarian group Save the Children said that about seven children have died of Ebola every day—for a total of 961 children—since the outbreak was detected in May.

Yesterday, Yakima County, Washington, officials reported an H5N1 highly pathogenic avian influenza (HPAI) infection in a resident exposed to infected dairy cows. The case comes a week after the state’s first H5N1 detection in dairy cattle at two Yakima County farms. The person is not seriously ill and is isolating at home. The risk of avian flu to the general public remains low, the news release said.

Florida has added 72 new locally acquired cases of dengue fever in its latest week of reporting, for a total of 368 for the year through October 10. It is the largest US dengue outbreak in decades, affecting eight counties. Most cases (310) have been in Hillsborough County, home to Tampa, but cases are increasing in Pinellas County (37).

Four cases of plague have been confirmed in four districts in Madagascar since the end of July, and five more suspected cases were detected last week, according to media reports. The type of plague, which is caused by the bacterium Yersinia pestis, wasn’t specified. About 200 contacts of the patients have been given preventive treatment to stem further transmission, and the government has launched flea insecticide spraying operations and awareness campaigns focused on hygiene and rodent control.

Eight cases of Middle East respiratory syndrome (MERS), including one death, were confirmed in Saudi Arabia from January 1 to October 5, the World Health Organization reported this week. MERS is a viral zoonotic disease for which dromedary camels are the primary animal reservoir; two patients reported direct contact with camels, while the rest had no known camel exposure. Officials say the cases aren’t epidemiologically linked.

This week, the Global Polio Eradication Initiative noted 14 cases of polio in seven countries. Afghanistan and Pakistan each documented one case of wild poliovirus type 1, the Democratic Republic of Congo logged seven cases of circulating vaccine-derived poliovirus type 2 (cVDPV2), Madagascar reported two cases of circulating vaccine-derived poliovirus type 1 (cVDPV1), Mali noted two cVDPV2 cases, Nigeria documented one circulating vaccine-derived poliovirus type 3 case, and Somalia added one cVDPV1 case.

(Note: Reposting this because previous post link had some embedded tracking)

They had a potluck that day.

LEBANON, Tenn. (WSMV) - Newly released 911 calls show how a reported illness affecting workers at a Walmart fulfillment center in Lebanon quickly grew from one employee needing medical help to dozens of people reporting symptoms.

In the first call, a facility employee told dispatchers that a worker was in a restroom vomiting and experiencing fatigue.

The caller initially described the situation as a possible food-poisoning incident and said a homemade rice dish may have been involved.

During a follow-up call, the employee told dispatchers that a slew of workers had been affected, with at least four considered very ill.

Wilson County emergency crews ultimately triaged about 25 to 30 people at the facility and transported 19 people to hospitals for treatment.

Measles infections make people miserable for up to two long weeks, commonly causing dangerously high fevers, a painful sensitivity to light and, of course, a tell-tale red rash.

Sufferers who escape without developing pneumonia, brain swelling, or other serious complications may believe the worst is over. 

Yet the measles virus has only gotten started.

The virus also damages the immune system, leaving people vulnerable to other infections for up to five years.

“The rash and the fever, that’s the tip of the iceberg,” Michael J. Mina, MD, PhD, coauthor of two seminal studies in Science on the effect of measles on the immune system, told CIDRAP News. “The majority of the damage being done is under the surface.”

The measles virus hijacks the immune system, using specialized memory cells to make copies of itself before blowing them up, Mina said. By deleting the body’s memory of earlier infections, measles causes a condition called “immune amnesia.”

Without those memory cells, the body essentially forgets how to fight off infections it defeated before. That leaves people newly vulnerable to bacteria and viruses against which they were once protected, either through infection or vaccination.

Oct 15 (Reuters) - The European Food Safety Authority (EFSA) and the European Centre for Disease Prevention ​and Control (ECDC) said on Thursday that as ‌of early October, 18 European countries had reported 1,855 people being infected by the West Nile virus ​since the beginning of 2026, including 141 ​deaths.

"In 2026, WNV has reached record levels ⁠in Europe, with the number of human ​cases and animal outbreaks surpassing historical records," Giusi ​Amore, Scientific Officer in EFSA’s Biological Hazards and Animal Health & Welfare unit, told Reuters.

The number of human cases ​in Europe increased by 769 since the ​previous report in September

The number of cases reported in the ‌EU/EEA, ⁠at 1,715, is well above the average of 693 cases over the past decade, the report says

Greece and France reported their highest numbers ​of human ​cases ever, ⁠at 445 and 144 respectively, while Italy remains the most affected European ​country with 748 cases

Fifteen European countries ​reported ⁠511 outbreaks in animals from the horse family and 595 outbreaks among birds

Transmission season of the ⁠mosquito-borne ​virus is nearing its end, ​but low-level transmission may continue in the coming weeks...

[...] Siberia’s vast wilderness harbors natural reservoirs of pathogens, from fleas that spread plague found in marmots and squirrels to ticks bearing encephalitis to the ancient pathogens frozen in the layer of permafrost.

The Russian institute where the lab technician worked was set up in the 1930s as a plague prevention station to curb outbreaks of the deadly bacterial disease that periodically affected local populations as well as people in neighboring Mongolia and China’s Manchuria region. The disease, for which early antibiotic treatments were pioneered that decade, could be spread through contact with marmots, which were hunted for meat and sometimes eaten undercooked or even raw, like in a 2019 case of a Mongolian couple.

The settlement of Siberia, which had a 19th-century gold rush and served as a place of exile for criminals under the Russian Empire, connected the remote region to the western parts of the empire and raised the risk of plague spreading farther west, much as epidemic diseases from European Russia, such as cholera and typhus, easily reached Siberia through migrating workers and because of the near-total absence of medical care.

A study published this year suggested that the bands of hunter-gatherers who inhabited the Lake Baikal region were the victims of the earliest known plague outbreak, about 5,500 years ago. To this day, plague remains endemic in parts of Siberia and the Russian Far East, where the bacterium persists naturally among wild rodents.

Human cases in Russia are rare, however. The country’s last recorded human infection was in 2016, when a 10-year-old boy in the Altai region contracted plague after contact with a marmot.

The threat of dangerous disease comes not only from wildlife but also from the millennia-old microbes and viruses stored in the permafrost that underlies the vast majority of the region.

About a decade ago, a group of researchers isolated “zombie viruses” from Siberian permafrost, raising fears that a new global medical emergency could be triggered by a disease from the distant past.

The permafrost, a dark, cold, oxygenless mass, is a perfect storage container for biological material, and scientists believe that at its deepest levels it may contain viruses up to a million years old, far older than Homo sapiens, the modern human species.

In 2023, the researchers — led by Jean-Michel Claverie of Aix-Marseille University in France — published a landmark study in the journal Viruses documenting the revival of ancient viruses from the Siberian permafrost.

The report warned that accelerating permafrost thaw caused by climate change poses a potential public health threat by releasing dormant pathogens. Claverie’s team isolated 13 ancient viruses taken from locations across Siberia, belonging to five new viral groups. The oldest, a Pandoravirus yedoma, had been frozen solid beneath an underground lake for 48,500 years, while other, younger strains (around 27,000 years old) were extracted from the remains of a woolly mammoth’s stomach and from mammoth wool.

Other researchers have noted that although the revived viruses were able to infect amoebas in lab conditions, it is unclear whether such viruses could infect animals or humans, or find a host outside a controlled laboratory.

Claverie and his team cautioned at the time that unknowns remain buried in the permafrost, and a warming climate, which would also open previously untouched lands to deeper development, could expose people to pathogens that affect humans.

In 2016, climate change played a role in unleashing anthrax in the remote Yamalo-Nenets region of Siberia, experts said at the time. Unusually high temperatures that summer, soaring to 95 degrees Fahrenheit, melted permafrost, and according to one hypothesis, exposed an infected reindeer carcass. The pathogen spread to living reindeer and eventually to a community of nomadic herders, where a 12-year-old boy died. [...]

Measles is sometimes dismissed as an unserious disease or ‘just a rash.’ But the highly contagious virus can cause serious illness not just during initial infection but years later, after patients appear to have made a full recovery.

This delayed complication, a rare, almost invariably fatal brain disease known as subacute sclerosing panencephalitis (SSPE), is highlighted in a new report published yesterday in Emerging Infectious Diseases.

For the report, researchers from the Centers for Disease Control and Prevention looked at 20 children from the Philippines, where measles outbreaks occurred in 2010–11, 2013, and 2018-19. The most recent outbreak was the largest in the World Health Organization Western Pacific Region. All children in the report were admitted to the pediatric hospital in Quezon City from 2007 through 2022.

Larger wave of SSPE may be on horizon

All four children with estimated measles infection dates corresponding to the 2018-19 outbreak were hospitalized between 2020 and 2022, two to three years after their initial infections. Because SSPE is latent for years after initial infection, those cases “most likely represent the leading edge of a postoutbreak wave,” notes the report, and “additional cases might emerge over the coming years.”

Ten of the 19 children in the study with an estimable infection age contracted measles before they were old enough for routine vaccination at nine months (when the Philippines schedules its first routine dose). The median age at hospital admission for SSPE was 6.2 years.

Eighty-five percent of the children had received at least one measles-containing vaccine, but the report emphasizes that SSPE results from naturally circulating measles that spreads between people, not from the weakened measles virus used in vaccines.

First-dose vaccine coverage in the Philippines declined from 92% in 2004-07 to 64% in 2021. Reported measles cases climbed from 2,428 in 2017 to 48,525 in 2019.

All 20 children admitted to the hospital for SSPE had worsening brain and nervous system function. All 17 screened for measles antibodies in their cerebrospinal fluid tested positive, and all 13 screened for measles antibodies in their blood tested positive. [...]

Still, the findings underscore the need for stronger measles and SSPE surveillance and sustained two-dose vaccination coverage, including supplementary immunization during outbreaks, the authors conclude.

The grandfather and grandmother died at their home in the commune of Andranolalina, and the grandson died at the hospital in Midongy Atsimo. Three members of the same family who, according to initial reports, died from pneumonic plague. As soon as the cases were reported, health authorities mobilized teams in the commune to carry out response activities, including disinfection and pest control. Nearly 200 people who had been in contact with suspected or confirmed cases are also receiving prophylactic treatment.

According to information provided by a local health official, three patients arrived at the Midongy Atsimo hospital on October 9. One of them, a man in his twenties, died, while the other two remain hospitalized and are continuing their treatment. The other two deaths occurred within the same family in the community toward the end of September. In total, five cases of pneumonic plague have been recorded in this commune.

Community mobilization, however, still faces a challenge. Despite awareness campaigns, some people delay seeking medical attention and only go to the hospital when symptoms become severe, our source laments. To limit the spread of the disease, a team from the local Joint Planning Body visited the area to raise awareness among residents.

Around fifteen homes were also sprayed with disinfectant. Contact tracing and outreach efforts are continuing. Health authorities also indicate that surveillance has been stepped up, especially since Midongy Atsimo is one of the country's plague hotspots, particularly between September and December.

Vigilance is also being maintained in Iakora, where a suspected case of bubonic plague has been reported. As in Midongy Atsimo, rapid diagnostic tests performed on patients in Iakora have come back positive, in addition to samples sent to the Pasteur Institute of Madagascar. Laboratory results are awaited to confirm the diagnosis. In the meantime, response activities are already underway on the ground to limit the risk of further spread.

“I have worked in humanitarian health in this region for decades and helped lead responses to several Ebola outbreaks. I have never seen one get this far ahead of us,” Heather Kerry, the country director of the International Rescue Committee in the Democratic Republic of Congo, writes in a guest essay for Times Opinion. More than 140 days after the outbreak was declared, the threat is still spreading, and much of it is happening outside of what is being tracked.

Controlling the outbreak has been made significantly harder by U.S. government funding to surveillance, preparedness and treatment drying up in 2025. “Budget reductions forced my organization, the International Rescue Committee, to cut funding to the health facilities focused on primary care in Ituri Province, where this outbreak began,” Heather says. At the same time, however, “the challenge is not only a lack of resources. It is also a lack of trust.”

Heather continues:

Decades of violent conflict, corruption and institutional neglect have fueled public distrust of health care providers, international actors and government institutions. Rumors that the Ebola outbreak is a hoax or was fabricated by humanitarians seeking to make money are widespread. My colleagues working on community outreach in Bunia told me that a mother did not take her children to a clinic to be checked for Ebola when they had a fever because she believed the Ebola response was a moneymaking scheme.

In some cases, that distrust has turned violent. At least a dozen health facilities have been attacked during this outbreak. In July, a health center was stormed by an armed group who threw stones at the center. Several Ebola patients fled. When I visited a few weeks after the attack, International Rescue Committee colleagues and health workers recounted hiding during the attack. Several told me that their main worry was their families, whom they could not reach until they got out.

More broadly, distrust has made it harder for health workers to track the virus. Contact tracing, a key tool in slowing the spread of the virus, has improved significantly, although it’s still short of what’s needed. The bigger problem is that most people who have contracted Ebola in this outbreak were never on a contact list in the first place. Just over a third of confirmed cases so far were known contacts of people infected; the rest emerged outside any known chains of transmission. Health workers told me that this is in large part because many people who think they have Ebola are choosing to stay home.

Read the full piece here, even if you’re not a Times subscriber.

Australians have been cautioned to be on high alert amid increased encounters with bats.

In just two weeks, 43 people in New South Wales were bitten or scratched by bats, NSW Health announced on Monday, Oct. 12 — more than quadruple the number of encounters reported during the same period last year. In the wake of the increase, NSW Health warned all residents to be vigilant and avoid any contact with bats.

The increase is especially concerning as any bats on the continent could transmit Australian bat lyssavirus, which has no known cure, according to the Australian Center for Disease Control. The virus causes a “rare but fatal” disease in humans, most commonly transmitted through a bat bite or scratch.

“We want people to assume that any bat could carry Australian bat lyssavirus, which is a close relative to the rabies virus and very dangerous to humans,” said Keira Glasgow, director of health protection at NSW Health.

She added, “It is incredibly rare for Australian bat lyssavirus to transmit to humans, but once symptoms of lyssavirus start in people who are scratched or bitten by an infected bat, sadly there is no effective treatment.” [...]

Unannounced drills to assess healthcare facility readiness to manage infectious disease outbreaks in three areas of the United States revealed variable adherence to containment protocols, according to a new study published in Morbidity and Mortality Weekly Report.

Using a simulated avian flu scenario involving an A(H5) strain with professional actors as patients, local and national public health authorities conducted 73 drills in 69 emergency departments, urgent care centers, and outpatient clinics in New Jersey, New York, and the US Virgin Islands from January to June 2026. The aim was to assess facilities’ ability to rapidly identify and isolate patients with suspected high-consequence infectious diseases.

“Successive recent outbreaks of viral hemorrhagic fevers, novel coronaviruses (e.g., COVID-19), monkeypox [mpox] virus disease, measles, and avian influenza A(H5) have reinforced the importance of rapidly recognizing and safely managing patients with potentially severe transmissible infections at health care facility points of entry, to protect health care workers, patients, and surrounding communities,” the authors wrote.

Facilities conducted symptom screening in 93.2% of the drills, documented travel history on patient arrival in 79.5%, and asked about exposure to avian flu in 9.6%. In 82.2% of drills during which the patient was appropriately masked, the median time from arrival to masking was two minutes, one minute short of the target.

Of 71.2% of drills that included patient isolation, the median time to isolation was 11 minutes, one minute shy of the 10-minute goal. A combination of masking and isolation took place in 60.3% of exercises. Patient actors were identified as being at risk for avian flu in 63.4% of cases.

Infection prevention-and-control (IPC) teams were notified or scheduled to be notified in 54.8% of drills, and staff wore all recommended personal protective equipment (PPE) in just 25.0% but wore none in 5.9%. [...]

A 39-year-old woman in Franklin County, Pennsylvania, has died after being diagnosed with measles, officials said.

The Franklin County Coroner's Office said that the woman died Saturday and that she had several underlying conditions, including a past diagnosis of measles with treatment.

"This is the first death in Franklin County in many years with a patient with a recent history of a measles diagnosis and meets the definition set forth by the Pennsylvania Department of Health for a measles-associated death," the coroner's office said.

The coroner's office said it is not releasing any additional details surrounding the case that could identify the individual and no indication was given as to whether the woman was vaccinated or not.

Los Angeles might be best known for blue skies, beaches and film premiers — but for the last several years it’s held another, unenviable distinction: the most mosquito-infested city in America.

And this year has been especially nightmarish, thanks to a series of heatwaves and an extra-powerful El Niño. Locals have called it a summer of “living hell” as clouds of mosquitoes swarm backyards and leave diners at open air patios scratching their ankles.

That double whammy of heat and humidity is making 2026 one of the worst mosquito years in recent history, causing a spike in cases of West Nile virus and raising fears that the nuisance bugs could spread other diseases including dengue, brought in by travelers. With moisture in this week’s forecast and overnight temperatures likely to stay above 50F (10C), there seems to be no end in sight for a problem that local authorities have struggled to contain for the last decade.

“I’ve been here my whole life and the amount of mosquitoes I’ve seen this summer has been insane,” said one TikTok user in a video with more than 20,000 likes. “Everyone is talking about them … You can’t even go to your back yard. You can’t even sit in your car with the windows down. They’re infested everywhere.”

Southern California residents have struggled all year to keep the winged bloodsuckers at bay. Some have resorted to sleeping in long sleeves after failing to kill off the mosquitoes that colonize their homes. Others have tried to seal off the cracks below their doors with towels.

“It’s an absolute nightmare,” Truman Hedding, an El Segundo resident, told Fox 11 News earlier this year. “We invest a lot of money to live in a beautiful town like El Segundo. The last thing we want is to stay up all night fighting mosquitoes.”

Los Angeles county has documented more than 180 cases of West Nile virus this year, according to the county public health department – the highest number in nearly a decade. And mosquito season is still far from over.

“This year in particular for our area has been higher mosquito activity and higher disease activity,” said Anais Medina Diaz, communications director for the San Gabriel mosquito and vector control district. “We can attribute that to some connection to the environment and how warm it’s been this year – particularly because we had a very warm winter. [...]

I am doubtful that 120 people have food poisoning at a distribution.

About 120 people became sick during a mass illness incident at a Walmart distribution center in Lebanon, Tennessee, with roughly 30 requiring hospitalization, according to local reporting citing Wilson County emergency officials.

The illnesses developed from late Thursday night into Friday morning, with nausea and vomiting among the symptoms reported. WKRN reported that the Wilson County Emergency Management Agency provided the figures.

Food poisoning is suspected, but officials have not confirmed what caused the illnesses. No particular food, meal or source has publicly been identified as responsible.

As of Sunday, there also appears to be no public statement from WCEMA or the Tennessee Department of Health about the incident. WKRN reported that Wilson County and Lebanon officials did not respond to the station's requests for additional information Sunday.

The television station reported that approximately 30 of the roughly 120 people who became sick were hospitalized for nausea and vomiting.

The incident occurred at Walmart's distribution operation in Lebanon, a city east of Nashville in Wilson County. The Wilson County Emergency Management Agency provides emergency medical, fire, and emergency management services in the county.

The available reporting does not establish whether all of those affected were Walmart employees or whether other workers or visitors were among the patients.

It also remains unclear whether everyone who became ill had eaten the same food, whether a particular meal or vendor is being examined, or whether testing has identified a pathogen or another cause.

Although food poisoning is one possibility, the cause remained unconfirmed as of Sunday.

That distinction is significant in an incident involving a large number of people becoming sick over a relatively short period. Symptoms such as nausea and vomiting can have multiple causes, and identifying a foodborne outbreak can require interviews, laboratory testing and comparisons between what affected people ate or were exposed to.

No public advisory or incident-specific announcement from Tennessee health officials had surfaced as of publication, and WCEMA's website did not contain a public statement detailing the incident.

A new study has found that three polar bears found dead in Alaska in 2023 and 2024 were infected with highly pathogenic H5 avian influenza, the same clade 2.3.4.4b viruses that have spread through wild birds, poultry, and mammals across North America.

The study's authors offered a notable caveat. "These data indicate that HPAIV infection may represent an emerging threat to polar bear health within the Alaska Arctic; though population immunity seems to be building and may protect this species from widespread demographic impacts of disease," they wrote.

[..]

Signs That Immunity May Be Building

The most important nuance is the evidence of exposure without death. When animals survive infection, they develop antibodies that show up in blood tests. A U.S. Geological Survey data release published in May 2026 documented blood samples from Alaska polar bears tested for prior exposure to these viruses.

A separate study from Norway points the same way. Researchers reported H5N5 bird flu in a dead yearling polar bear and a walrus in Svalbard in May 2026. In blood samples, H5 antibodies appeared in 75% of polar bears tested in 2023 and 97% in 2024 and 2025, compared with none from 2014 to 2022. That work was posted as a preprint and has not yet been peer reviewed.

Together, the findings suggest many bears have been exposed and survived — a very different picture from a species-wide die-off. That would be encouraging for a species already under pressure from shrinking sea ice. Still, researchers cannot yet say how long protection lasts, whether it protects against newer virus strains, or how many deaths go unnoticed in remote areas where carcasses are quickly scavenged.

[..]

The University of Southern Denmark confirmed that it has given the green light to a controversial study in Guinea-Bissau, funded with $1.6 million from the US Centers for Disease Control and Prevention (CDC), that plans to offer life-saving hepatitis B vaccines to only half of enrolled babies.

News of the study, first reported in December by CIDRAP News, prompted an international outcry from health groups and political leaders, who condemned its design as unethical. Those concerns led Guinea-Bissau officials and administrators at the Danish university to place the study on hold for several months.

Nearly one in five people in Guinea-Bissau are infected with hepatitis B, which kills 15% to 25% of people with chronic infections by causing cancer or liver failure. Vaccinating babies at birth is safe and can prevent lifelong infections.

Yesterday, citing unnamed sources, Rolling Stone broke the news that the Danish university had approved the clinical trial and that CDC leaders were pushing for the study to resume.

The Department of Health and Human Services, which oversees the CDC, did not respond to questions before press time.

The Danish researchers leading the study in Guinea-Bissau, Peter Aaby, PhD, and Christine Stabell Benn, MD, PhD, could not be reached for comment. In response to earlier criticism, their research group, the Bandim Health Project, defended their choice to withhold the birth dose of hepatitis B vaccine from half of the 14,000 newborns to be enrolled in the clinical trial.

In a statement on Bandim’s website, researchers wrote, “No child enrolled in the study will receive fewer vaccines than under current national policy in Guinea-Bissau,” a developing country with far fewer resources than the United States and Europe. Guinea-Bissau does not currently vaccinate newborns against hepatitis B, as recommended by the World Health Organization, but plans to begin in 2028.