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 US Food and Drug Administration (FDA) is investigating a possible cancer risk linked to Novartis' gene therapy Zolgensma after the Swiss drugmaker reported several cases of tumours in patients who had received the treatment. It included two patients aged less than two years old with spinal muscular atrophy (SMA) in which investigators found evidence linking the tumour to the therapy.

Novartis's SMA Drug Under Investigation For Causing Tumour Growth

Zolgensma is a one-time gene therapy used to treat children under two years of age with spinal muscular atrophy (SMA), a rare genetic disorder that causes progressive muscle weakness. More than 6,000 patients have received the treatment since its approval in 2019.

In a safety update issued on November 6, the FDA said it had received reports of neoplasia, or tumour formation including malignancy, known as insertional oncogenesis. This occurs when genetic material delivered by a gene therapy becomes integrated into a patient's DNA and contributes to abnormal cell growth.

In two cases, molecular analysis of tumour tissue showed that DNA from the therapy's viral vector had integrated into the patients' genomes within the GLI1 gene, which can promote cancer when activated. The FDA said it was also investigating a third tumour linked with GLI1.

The agency said tumours had been found in the central and peripheral nervous systems, spinal and paraspinal regions, and kidney.

Also read: Drug-Resistant Epileptic Seizures Reduce By Over 90% With Experimental Gene Therapy

What Has The FDA Said About The Risk?

The FDA is assessing whether regulatory action is needed and is reviewing whether the long-term safety studies address the risk.

However, it stressed that the benefits of both Zolgensma and Novartis' other SMA gene therapy, Itvisma, continue to outweigh their potential risks for their approved uses.

The two therapies use the same viral vector and genetic material but are administered differently. Zolgensma is given through an intravenous infusion to children under two, while Itvisma is injected into the spinal canal and is approved for adults and children aged two and older. The FDA said no cases of tumour formation had been reported following Itvisma treatment so far.

The risk of tumour formation due to viral DNA integration is already mentioned in Zolgensma's information as a theoretical risk. The FDA said patients receiving either treatment should be monitored for tumour formation.

Also read: India Proposes Stricter Drug Rules: Tougher Quality Checks, Licence Suspension

What Novartis Said?

Novartis said the two patients whose tumours showed evidence of vector DNA integration had undergone treatment and continued to be monitored.

In a statement, the company said, “Patient safety is our priority. In each case, we timely and appropriately notified health authorities and will continue to work with them on next steps.”

The company also said it had received nine tumour reports since Zolgensma's approval and that the risk was included in the drug's prescribing information.

The disclosures have raised questions among families and patients about when the information was shared. SMA Europe urged the company to explain what is known, what remains uncertain and what the findings could mean for children who have already received treatment. Novartis did not provide details on where the two new cases were in its statement.

The United States is in the midst of one of the worst measles outbreak. It has reported more than 5,000 measles cases in 2026, marking the highest annual total cases since 1991.

This has raised concerns that the country could lose its measles elimination status after more than 25 years.

Measles Cases In The US Cross 5,000

Also read: EXCLUSIVE: Ex-CDC Vaccine Advisor Says Measles Outbreak Bigger Than Reported, Slams RFK Jr’s ‘No-See Evil’ Approach

According to an update issued on November 6, the US Centers for Disease Control and Prevention (CDC) reported 5,182 confirmed cases as of November 5. This is the first time since 1991 that the annual number of infections has crossed the 5,000 mark.

The latest figure marks an increase of 330 cases from the previous week. The CDC also reported 562 hospitalisations due to measles this year, which accounts for 11% of confirmed cases.

The outbreak has spread across 47 jurisdictions and 43 outbreaks reported so far in 2026. Approximately around 96% of infections have been linked to outbreaks, while 96% of people infected were either unvaccinated or their vaccination status was unknown.

The expanding measles outbreak has sparked concerns about the country's ability to maintain the elimination status it achieved in 2000.

Could The US Lose Its Measles Elimination Status?

Also read: 'It’s The Best-Studied Vaccine In Human History': Former CDC Adviser Busts Common Myths About COVID Vaccines

The US declared measles eliminated in 2000, meaning that the country had stopped continuous transmission of the virus for at least 12 months, but infections could still occur when people brought the virus into the country from abroad. However, recent outbreaks have raised concerns that measles could become endemic again.

According to the CDC, elimination status is determined by the absence of continuous measles transmission in a geographical area for 12 months or longer, supported by an effective disease surveillance system.

The United States is facing a review of its elimination status by the Pan American Health Organization (PAHO), which is expected to assess the country's progress in controlling transmission during its November 2026 meeting.

The review will examine whether the ongoing outbreaks represent sustained transmission of the virus and whether the country continues to meet the criteria for elimination. Losing elimination status would that the country had failed to interrupt sustained transmission of the virus.

The Americas region had already lost its measles elimination status in November 2025 after Canada experienced continuous transmission for at least 12 months.

What Happens If The US Loses Its Elimination Status?

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Losing measles elimination status would mark a major setback for public health efforts that successfully interrupted continuous measles transmission in the country in 2000.

It would also signal that the virus is circulating continuously within the population rather than appearing mainly through imported infections that cause outbreaks that get eventually contained.

However, elimination status can be regained if sustained transmission is interrupted and the required criteria are met. Public health experts continue to emphasise the importance of maintaining high vaccination coverage, identifying cases quickly and responding to outbreaks promptly.

Who Is Being Affected By The US Measles Outbreak?

The latest CDC data show that measles is affecting people across different age groups. Adults aged 20 and older accounted for 2,132 cases, followed by 2,104 infections among people aged five to 19. Children younger than five accounted for 908 cases.

The CDC reported four measles deaths in 2026, compared with three during the whole of 2025. However, the CDC's national death count differs from figures reported by individual state health departments because the agency uses National Center for Health Statistics mortality data for its official tally.

Pennsylvania has been among the hardest-hit states, reporting 1,487 cases, 287 hospitalisations and six associated deaths, according to Reuters. The outbreak has also spread to South Carolina and Utah, which reported 670 and 536 cases, respectively.

According to state health department reports, the country has recorded eight measles-related deaths this year: six in Pennsylvania, one in New York and one in Wisconsin. At least four involved children or infants.

Life-threatening bleeding episodes among US infants have risen sharply as more parents refuse the routine vitamin K shot given at birth, two new studies have found.

Published in JAMA and JAMA Pediatrics, the studies found that the proportion of newborns who missed the vitamin K shot more than doubled between 2017 and 2025, reaching 6.8%. These infants were also more likely to experience bleeding, including bleeding in the brain.

Although the studies do not establish causation, the parallel rise in refusals and bleeding episodes is significant, said Dr Steven Woolf, an epidemiologist at Virginia Commonwealth University and lead author of the JAMA Pediatrics study, as reported by NBC News.

"Now we're stepping away from that, and we're seeing the consequences," Woolf said.

Vitamin K shots have been standard newborn care since 1961 and help prevent vitamin K deficiency bleeding (VKDB), a rare but potentially life-threatening condition.

Infant Bleeding Episodes Nearly Quadrupled Since 2017

Woolf and colleagues analysed medical records of more than 11 million infants aged six months and younger between 2017 and 2025.

During this period, the proportion of newborns receiving a vitamin K shot fell from 97.7% to 95%, while vitamin K deficiency bleeding nearly quadrupled.

The researchers identified 5,217 bleeding events during the study period. The rate in 2025 was approximately double that in 2024, Woolf said.

The researchers noted that the increase coincided with declining public trust following the COVID-19 pandemic, growing vaccine hesitancy and parental scepticism about routine newborn interventions.

Vitamin K Refusals More Than Double To 6.8%

A separate JAMA study by Dr Kristan Scott and colleagues analysed medical records of more than 5.2 million US infants born between 2017 and 2025.

The proportion of newborns who missed the vitamin K shot rose from 3.1% in 2017 to 6.8% in 2025. It had reached 5.1% by the end of 2024.

The study also found that infants who did not receive the shot had:

• A 47% higher risk of bleeding during their first six months.
• More than twice the risk of bleeding in the brain.
• More than twice the risk of death associated with a bleeding diagnosis during their birth hospitalisation.

The authors estimated that one additional bleeding event would occur for every 114 newborns who missed the vitamin K shot.

Separately, an analysis of more than one million births by health data company Truveta for Reuters found that vitamin K refusals increased by more than 57% between January and June 2026.

Why Is Vitamin K Important For Newborns?

Vitamin K is a fat-soluble nutrient essential for blood clotting and bone health. Newborns naturally have low levels, leaving them vulnerable to VKDB.

The American Academy of Pediatrics (AAP) has recommended a vitamin K injection for all newborns since 1961.

Without adequate vitamin K, babies can develop spontaneous bleeding, including severe internal bleeding and bleeding in the brain. These episodes can cause permanent brain damage or death.

Importantly, the vitamin K shot is not a vaccine. It is a one-time injection given shortly after birth to protect babies against VKDB.

Breast milk contains relatively little vitamin K. Exclusively breastfed babies who miss the birth injection therefore remain vulnerable to deficiency bleeding.

The researchers also found increased use of oral vitamin K. However, oral doses are less effective than intramuscular injections, particularly in preventing late-onset VKDB, which can occur weeks or months after birth.

Why Are More Parents Refusing Vitamin K Shots?

Vitamin K refusals have risen since the COVID-19 pandemic amid growing parental concerns about vaccines and routine newborn interventions.

Health experts have also raised concerns about declining trust in health authorities and mixed messages surrounding preventive care.

Refusals have accelerated under US Health Secretary Robert F Kennedy Jr, who has questioned vaccine safety and overseen changes to federal childhood vaccination recommendations.

A US Department of Health and Human Services spokesperson said the Centers for Disease Control and Prevention (CDC) continues to recommend vitamin K shots for newborns. However, the department did not say whether the agency would begin tracking refusals or associated bleeding episodes.