Mysterious Fog in the US , Canada and UK: A dense, eerie fog with a "burning chemical-like smell" has spooked a good part of North America and parts of the United Kingdom and Canada. With social media amplifying all concerns, this phenomenon has sparked attention across all social media platforms. However, at the heart of this mysterious fog are a conjunction of natural events, social psychology, and environmental conditions that culminated in all the conspiracy theories and public health fears. Here's a closer look at the mysterious fog, its potential causes, and the societal response it has triggered.

Fog that Feeds Fear

The first reports of this "mysterious fog" came in from Florida where a resident said that they experienced respiratory symptoms, feverish warmth, and stomach cramps after contact with the fog. Similar stories started flooding social media, and within a day or two, a sinister force seemed to sweep across the United States, Canada, and parts of the UK. From Texas to Minnesota, people reported weird odors and health issues that they thought were linked to this bizarre atmospheric event.

Some witnesses were said to see "white particles" swirling through the air; theories ranged from a chemical attack or experimental weapon to drone-related chemical dispersals and references to historical military experiments, such as the infamous 1950s "Operation Sea-Spray."

Fuel to the fire were added when videos and posts, hundreds of thousands in number, began circulating on social media sites like TikTok and X (formerly Twitter) speculating on the origin of the fog. Hashtags like #ToxicFog went trending for days. Hysteria created a self-reinforcing loop in which every post spurred further scrutiny and fear.

Scientific Explanation of the Dense Mysterious Fog

1. What is Fog?

Fog is essentially a low-lying cloud formed when the air temperature cools to its dew point, causing water vapor to condense into tiny droplets or ice crystals. Several types of fog—advection fog, radiation fog, and valley fog—can form depending on conditions such as warm, moist air moving over cooler land or when temperatures plummet rapidly under clear skies.

2. Why the Chemical Smell?

Such chemical-like smell as reported during the occurrence of fog events is sometimes attributed to air pollution. It acts like a sponge, where it absorbs these pollutants, which include sulfur dioxide and nitrogen oxides, among others, that emit from industries. This mixture, therefore, leads to a stench that could be mistaken as unnatural or even toxic.

Also Read: Health Concerns Rise As US, Canada, and UK Come Under The Blanket Of Thick, Dense, Toxic Fog

3. What are the Health Concerns?

High moisture levels from fog can significantly exacerbate symptoms related to respiration, but especially in already predisposed asthmatics and allergy patients. The connection of these symptoms with actual fever, stomach cramps, and puffy eyes is too remote. Experts assume that the irritating effects of entrapped pollutants trapped in fog tend to affect more the eyes and throat rather than the rest of the body affected by some report.

Psychological Effects of Mass Panic Caused by Social Media

Social media amplified a natural weather event into a health epidemic. It made the personal experience of individuals become a cause for fear and speculation, a domino effect.

According to psychologists, this is a concept of selective perception, wherein once people's attention is drawn to environmental anomalies, they begin to notice them. This mirrors earlier panics, such as the Seattle windshield pitting panic of 1954. Then, atomic bomb testing caused fear in many and started to have people looking at their windshields for small marks that they had not seen before. Likewise, postings on the strangeness of the fog probably increased public awareness and suspicion, with people looking to attach unrelated symptoms to the phenomenon.

The fog hysteria shares a commonality with other instances of mass panic, such as the "drone sightings" of recent years or the Cold War-era fears of biological warfare.

Also Read: Mysterious Fog Is Making Americans Sick

These events underscore how fear can cloud judgment, especially when amplified by social media and sensationalist headlines. While historical cases, such as "Operation Sea-Spray," offer concrete evidence of the existence of unethical experiments, the jump from a natural weather condition to theories of chemical attacks exemplifies a more modern trend of connecting unrelated dots, all wonderfully seeded in distrust and anxiety.

Despite the swirling rumors, meteorologists and scientists are in agreement that the mysterious fog is not as alarming as it seems. It is well known that fog traps and amplifies pollutants, especially in urban and industrial regions. Moreover, winter months are the most conducive for fog formation, so its recent prevalence is unsurprising.

On the other hand, environmentalists advise that the fog should wake everyone up to increased levels of pollution. The reported odors and health irritations could be just symptoms of far deeper systemic issues like industrial emissions and lack of control over air quality.

The authorities must be transparent in their communication to combat misinformation and allay public fears. Governments and environmental agencies must provide timely updates on weather phenomena, air quality, and health risks. Initiatives like real-time pollutant tracking and public education campaigns can help demystify natural occurrences while addressing valid environmental concerns.

The mysterious Canada fog is a compelling case study in how environmental events intersect with psychology and societal dynamics. While rooted in natural phenomena, the fog became a vessel for collective fears, amplified by modern technology and historical anxieties.

In this information era where communication occurs at an almost lightning pace, the fog becomes a metaphor that reminds everyone about scientific literacy, environmental responsibility, and an effective balance when considering public concern. Whether perceived as a marvel of nature or as a tale that serves to teach, it left a very powerful mark in people's minds.

The human brain may begin undergoing important immune changes much earlier than previously thought. A recent study found that these changes could help explain why the risk of dementia increases with age.

Researchers found that the hippocampus, the brain region responsible for learning and memory, experiences a major shift in its immune cells during the 40s and 50s.

The findings suggest that this change could lead to chronic inflammation associated with Alzheimer's disease and other forms of dementia in the future .

What Did The Study Find?

The study, conducted by scientists from the University of California San Diego, the New York Genome Center, and the University of California Irvine, analysed postmortem hippocampal tissue from 40 neurologically healthy adults aged between 20 and 95 years.

Researchers examined more than 1.2 million brain cells, discovering that around midlife, the brain's immune environment changes dramatically.

One of the biggest findings involved microglia, the brain's resident immune cells. While these cells normally protect the brain by clearing debris, fighting infections, and supporting neurons, researchers observed that they gradually shift into a more inflammatory state during middle age.

This altered immune environment resembles patterns commonly seen in neurodegenerative diseases like dementia.

Also read: World Brain Day: Climate Change Is Not Just Harming The Planet, It Could Also Be Affecting Your Brain

Link Between Ageing & Dementia

Scientists have long known that aging is the strongest risk factor for dementia. However, exactly how normal aging causes diseases like Alzheimer's has remained vague.

The new findings suggest that the process may begin decades before symptoms like memory loss appear.

Instead of viewing aging as a slow, continuous process, the study indicates that the brain may pass through a distinct biological transition during midlife.

Once this immune environment changes, it may make the brain more vulnerable to inflammation and cognitive decline.

Richard J. Hodes, MD, Director of the National Institute on Aging (NIA), said, "Aging is the single largest risk factor for dementia, but our understanding of how it drives disease is still incomplete. This previously hidden microglial shift, now uncovered by innovations in technology and thinking, may be an important clue to help us complete the puzzle."

The researchers also believe these immune changes may not simply be a consequence of aging but could actively influence how the brain ages.

Also read: Can One Partner's Dementia Raise the Other's Risk? New Study Suggests An Interesting Link

Could This Contribute In Dementia Treatments & Management?

Although the findings do not mean that everyone in their 40s or 50s will develop dementia, they provide researchers with a potential window for clinical intervention.

If scientists can identify or modify these immune changes before significant brain damage occurs, future therapies may be able to delay or even prevent neurodegenerative diseases.

Experts continue to recommend:

• Keeping blood pressure, blood sugar, and cholesterol under control.
• Exercising regularly.
• Getting adequate sleep.
• Eating a balanced, brain-healthy diet.
• Staying mentally and socially active.
• Managing hearing loss and avoiding smoking.

These lifestyle measures are already known to reduce several risk factors associated with dementia, and the new findings suggest they may be particularly important during the brain's midlife transition.

A six-year-old girl in China died after receiving an experimental gene-editing treatment for a rare neurodevelopmental disorder. The incident sparked scrutiny on ethics and safety of cutting-edge gene therapies, particularly when they involve children and individualized treatments.

The case, uncovered through a joint investigation by Science and Retraction Watch, sparked international concern as the child's death was never disclosed publicly, despite related preclinical research later being published in Nature.

What Happened?

According to the investigation, the six-year-old girl, identified by the pseudonym "Mei," had Snijders Blok-Campeau syndrome, a rare genetic condition. It caused symptoms like mild intellectual disability and developmental delays.

Her parents reportedly paid more than $800,000 to support development of a personalized ("n=1") gene-editing therapy designed specifically for their daughter's mutation.

In March 2025, she received a spinal infusion containing trillions of adeno-associated viruses (AAVs) carrying a CRISPR-based gene editor intended to correct the faulty gene in brain cells. Within days, she developed a severe immune reaction and died approximately one week after treatment.

An internal hospital review concluded that the most likely cause of death was an overwhelming immune response triggered by the viral delivery system rather than the gene-editing mechanism itself.

The controversy extends well beyond the patient's death. According to Science investigation:

• The child's death was not publicly disclosed.
• The child's treatment was omitted from a later Nature publication describing related preclinical work.
• Animal studies had reportedly shown warning signs, including severe liver and kidney toxicity at high doses.
• The girl's parents may not have been fully informed about the potential side effects of the therapy.

Following the investigation, local Chinese health authorities reportedly fined the hospital involved for faulty execution of the clinical research. Several experts have called for an independent review of the published research and greater transparency around experimental human gene-editing trials.

Also read: Ebola Outbreak in DR Congo Nears 3,000 Cases, 1,300 Deaths as UN Warns Virus Is 'Spreading Like Wildfire'

Bioethicists and gene therapy researchers say the case underscores the need for complete transparency whenever experimental therapies are tested on humans.

Hank Greely, director of the Center for Law and the Biosciences at Stanford University, told Science that the trial "shouldn't have gone to trial".

Pediatrician Marcelo Bellusci, who participates in gene therapy trials, told El País, "In this type of trial there can be serious side effects, but families are always informed about them. This team skipped the current rules."

About Gene-Editing Therapies

Gene-editing technologies such as CRISPR offer the possibility of correcting genetic mutations caused by diseases instead of simply treating symptoms. Several CRISPR-based therapies have shown remarkable success in inherited blood disorders, including sickle cell disease.

However, experts stress that therapies targeting the brain remain considerably more complex because they often require large viral doses and carry greater risks of immune complications.

As more individualized gene-editing therapies move toward human testing, experts argue that every serious adverse event must be reported promptly to regulators, journals, clinicians, and patients to ensure future treatments become both safer and more trustworthy.

Mongolia recently confirmed a suspected case of bubonic plague after a bacteriological laboratory delivered positive results. The National Center for Zoonotic Diseases confirmed on Friday that the case belongs to Mongolia's western Khovd province.

Mongolia Confirms First Human Case Of Bubonic Plague

According to reports, the patient contracted the infection after eating marmot meat during a visit to Ulaankhus soum in neighbouring Bayan-Ulgii province.

Mongolia's first confirmed case of bubonic plague has prompted officials to issue warnings against hunting and eating marmots, a known source of the deadly disease which is also considered a delicacy in the country.

The warnings also stated that individuals must avoid all forms of contact with the rodent, including handling their meat or internal organs. It also said avoid contact with sick or dead rodents as it could significantly increase the risk of infection.

The National Center for Zoonotic Diseases says 17 of Mongolia's 21 provinces are considered high risk regions for plague as the bacterium persists in wildlife.

Also read: What Was The Pseudo-Tuberculosis Like 'Syndrome K' Saved Thousand Lives During World War II?

Why Bubonic Plague Still Lurks In Mongolia?

The Black Death devastated Europe in the 14th century. Even today, a few countries still see cases of plague from time to time.

Humans typically get infected through flea bites from infected rodents, handling and close contact with infected animals and eating undercooked or raw marmot meat, which has been linked to several cases in Mongolia.

Mongolia has reported human plague cases to the World Health Organization since the 1980s. Sporadic infections continue to occur almost every year, particularly in the country's western and northern provinces.

The disease still lives centuries after it was eradicated because it is entrenched in wildlife rather than spreading continuously between people.

Humans are usually infected after being bitten by infected fleas or through hunting, skinning, or eating infected marmots.

Studies show that nearly 60% of Mongolia's reported plague cases since 1998 have been linked to close contact with infected marmots, highlighting why authorities repeatedly warn against hunting and consuming the animals.

Also read: How To Get Rid Of Fleas In Your House And Stop Them From Infecting Your Pets

Several infamous incidents related to the disease have sparked headlines in the last few years.

In 2019, a married couple died after eating raw marmot meat.

In 2020, a teenager also died after eating marmot meat, prompting temporary travel restrictions and heightened surveillance.

The latest confirmed human case in July 2026 follows the same familiar pattern.

Mongolia's challenge is not a new outbreak but an enduring zoonotic disease that resurfaces whenever humans come into contact with infected wildlife.

Where Else Does The Plague Still Exist?

Plague remains endemic in several parts of the world. According to the World Health Organization, the Democratic Republic of Congo, Madagascar, and Peru report the highest number of human cases globally. Since the 1990s, most reported cases have occurred in Africa.

Madagascar experiences seasonal plague almost every year, typically between September and April. The country drew international attention during a major 2017 outbreak, which caused more than 2,500 suspected, probable, and confirmed cases and over 200 deaths.

In the United States, plague is rare but has never disappeared. An average of about seven human cases are reported annually, mostly in rural parts of New Mexico, Arizona, Colorado, California, Oregon, and Nevada.

In 2026, Arizona reported its first human plague case in Apache County in more than a decade.

China has also reported occasional isolated human infections, particularly in Inner Mongolia.