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 Department of Health (DOH) reported 411 measles infections in Philippines' Northern Mindanao in 2025, which was a 11% increase from 371 cases in 2024. Health officials are now warning people that the situation may get worse in 2026, as rate of unvaccinated children in the region also rise.

In 2025, 75% of the patients were unvaccinated.

In order to prevent outbreaks, DOH-Northern Mindanao and local health offices said that they will be deploying teams to administer Measles-Rubella (MR) vaccines to children and people aged six to 59.

“There are (measles) outbreaks in various parts of the country because of low (immunization) coverage and that includes our region,” said Germaine Labadan, head of the DOH-X Family Health Cluster.

In 2025, only 56.7% of Northern Mindanao's eligible population received MR shots, which led to a herd immunity well below the target of 95%.

Cagayan de Oro, a highly urbanized city, recorded the region’s highest measles-rubella (MR) coverage at 87.21%, while Bukidnon lagged at 49.71%. Coverage in other areas remained low, with Misamis Oriental at 51.87%, Misamis Occidental at 52.05%, Iligan at 52.55%, and Camiguin at 53.73%.

As part of this year’s Measles-Rubella Supplemental Immunization Activity (MR-SIA), children will be given booster MR vaccines along with Vitamin A supplements. The 21-day campaign will run from January 19 to February 13.

“This is open to all eligible, regardless of the immunization status of the child because the vaccine serves as a booster,” Labadan said. This also includes children who completed the first and second doses. “Parents may present the immunization booklet, but it is not necessary because all will be given a new one,” she said.

What Is Measles?

Measles, also known as rubeola, is a highly contagious viral illness that typically causes fever, cough, a runny nose, red and watery eyes, and a distinctive red, blotchy rash that usually begins on the face and spreads downward. The virus spreads through the air when an infected person coughs or sneezes and can lead to serious complications such as pneumonia or brain inflammation. Despite its severity, measles is preventable through a safe and effective vaccine, as per the Mayo Clinic.

How Contagious Is Measles?

Measles is among the most contagious diseases in the world. The virus spreads through airborne droplets that can linger in the air or on surfaces for hours. Up to 90% of unvaccinated people who are exposed to measles will become infected. A single infected person can pass the virus to an estimated 12 to 18 others through close contact or shared spaces. People can transmit the virus days before symptoms become obvious and continue spreading it after the rash appears, according to the World Health Organization.

How Long Is Someone Contagious With Measles?

Someone infected with measles can spread the virus from four days before the rash develops to four days after it appears. The virus spreads so efficiently that about 90% of people who are unvaccinated or have never had measles will become infected after being exposed.

In November, Canada lost its measles elimination status following a significant outbreak, according to the Pan American Health Organization, which works closely with the World Health Organization.

“It’s important to say that all the other 34 countries in the region, they keep their certification as measles-free,” said PAHO/WHO Director Dr. Jarbas Barbosa at the time, as per NPR News.

U.S. health officials have also warned that genetic links between outbreaks in different states suggest continued spread.

“The trajectory that we’re looking at now is that we do anticipate more cases well into January,” Bell said. “What that means for us nationally in terms of how they are defining our designation in this country as having eliminated measles is unclear.”

Nipah virus case detected in India's West Bengal, where two nurses are suspected of being infected by the virus. The case has come 24 kilometers away from West Bengal's capital, Kolkata, in North 24 Parganas' Barasat, where the patients are on a life support at a private hospital.

The blood samples collected from the nurses, one male and one female, were sent to the Virus Research and Diagnostic Laboratory, ICMR, at the All India Institute of Medical Sciences (AIIMS) in Kalyani, which is around 50 kilometers north of Kolkata in Nadia. Another report has been sent to Swasthya Bhawan, the state health department headquarters. The two nurses one from Nadia's Kalyani and another from East Burdwan's Katwa, work at the same hospital where the have been admitted.

Reports say that the nurses went home to Katwa around 10 days back, from where they may have caught the illness. The female nurse was initially admitted to a hospital in Katwa, later moved to Burdwan Medical College. Her condition kept worsening, this is when she was admitted in Barasat's private hospital, she is currently in the ICU. The male nurse is also on the ventilator support. Both patients are kept in isolation.

Update On The Nipah Virus Spread By West Bengal's Health Authorities

The sources from Swasthya Bhawan said that officials were handling the situation with extreme alarm as Nipah virus has a high rate of mortality and could spread rapidly. The Telegraph reported that top health officials form Union health ministry, including Union health secretary are in touch with Bengal chief secretary Nandini Chakravarty and state health secretary Narayan Swarup Nigam.

The health department has now begun contract tracing in Nadia, East Burdwan, and North 24 Parganas.

Chakravarty also asked people to not panic and remain alert, while avoiding to spread misinformation and follow hygiene practices. The State government has also launched three helpline numbers — 03323330180, 9874708858, 9836046212 — for public queries.

Union Health Minister JP Nadda also wrote to West Bengal's Chief Minister Mamata Banerjee, assuring full support from Centre. Banerjee too visited the hospital late on Sunday night.

What Is Nipah Virus?

As per the World Health Organization (WHO), Nipah virus infection is a zoonotic illness that is transmitted to people from animals, and can also be transmitted through contaminated food or directly from person to person.

In infected people, it causes a range of illnesses from asymptomatic (subclinical) infection to acute respiratory illness and fatal encephalitis. The virus can also cause severe disease in animals such as pigs, resulting in significant economic losses for farmers.

Although Nipah virus has caused only a few known outbreaks in Asia, it infects a wide range of animals and causes severe disease and death in people.

During the first recognized outbreak in Malaysia, which also affected Singapore, most human infections resulted from direct contact with sick pigs or their contaminated tissues. Transmission is thought to have occurred via unprotected exposure to secretions from the pigs, or unprotected contact with the tissue of a sick animal.

In subsequent outbreaks in Bangladesh and India, consumption of fruits or fruit products (such as raw date palm juice) contaminated with urine or saliva from infected fruit bats was the most likely source of infection.

Human-to-human transmission of Nipah virus has also been reported among family and care givers of infected patients.

Nipah Virus Symptoms

• Fever
• Headache
• Breathing difficulties
• Cough and sore throat
• Diarrhea
• Vomiting
• Muscle pain and severe weakness

Wondering when you are most at risk of having a heart attack?

Dr Srihari Naidu, a triple board-certified in internal medicine, cardiology and interventional cardiology and cardiology professor at New York Medical College says that the winter season is when we're most susceptible to attacks.

He told HealthandMe: "Major cardiovascular studies have shown a link between cold exposure, including the drop in temperature during the winter months, and risk of heart attack. While it’s hard to pin point the exact reason, it is clear that cold exposure does make the heart work harder."

Heart attacks are one of the leading causes of death in the country. Four Indians experience a heart attack every minute, with one in four dying of the cause.

Experts have also noticed a rising trend of nearly 50 percent of heart attack patients being under the age of 40, with half of all heart attacks in Indian men occurring under 50.

Why Are Your More Likely To Have Attack In Winters?

According to Dr Naidu, falling temperatures can cause arteries to narrow, reduce oxygen flow and force the heart to work harder. This can lead to the thickening of blood and with time, cause a heart attack.

"For one thing, cold causes all the arteries in the body to constrict, so that more blood flow is in the central parts of the body like the gut and less on the surface where heat can be lost through the air. While this prevents hypothermia, it makes the heart work harder and need more oxygen itself. In addition, cold causes blood to be thicker, a phenomenon that could increase the risk of blood clots.

"This combination of the heart working harder, needing more oxygen and the blood being more prone to clotting results in a higher rate of heart attacks. In addition to this, people who already have blockages will experience more chest pain (angina) in the cold due to the heart working harder, and if this is tied to extra exertion, that risk could skyrocket."

Additionally, Dr Tamil Selvan Muthusamy, Consultant Cardiologist at Cardiac Vascular Sentral Kuala Lumpur (CVSKL) told HealthandMe: "Extreme pollution, winter illnesses like the flu can cause inflammation that can trigger heart problems and holidays activities can put extra strain on the heart when it's already working overtime from the cold."

Apart from this, Dr Y. Vijayachandra Reddy, Senior Consultant Cardiologist, Apollo Hospitals, Greams Road Chennai, also noted that hypertension, chest infections and excessive holiday drinking as well as smoking can worsen the risk of heart attack during this season.

He shared with the publication: "Chest infections and throat infections are quite common in the winter season. Intercurrent flu or other chest infections can cause an inflammatory milieu, which can lead to more ruptures of the cholesterol or atherosclerotic plaques in the blood vessels of the heart, leading to sudden precipitation of heart attacks.

"The holiday syndrome, wherein in the winter season, many holidays, weekends and people can take recourse to excessive recreational use of alcohol or smoking, which can lead to trouble."

Who Is Most At Risk?

Dr Naidu warns people who have a history of heart disease and other chronic conditions may be most at risk of having a heart attack and should attempt to maintain their body temperature to keep their heart safe and functioning.

"Taken together, people should understand that their baseline risk of a heart attack goes up significantly in the cold weather, especially if they have risk factors for heart disease such as smoking, high cholesterol, diabetes or hypertension, and should take precautions or simply avoid exercise or exertion in the cold weather.

"If any exertion is needed, dressing warmly to make sure the heart doesn’t have to work so hard to maintain body temperature should reduce risk. Most importantly, though, listen to your body, especially in the cold weather, as just being in the cold is a significant stress especially as we get older," he explained to the publication.

To prevent infection-caused heart attacks, Dr Reddy advises: "One of the protective mechanisms is for the vulnerable population to take annual flu vaccine and a lifetime pneumococcal vaccine."

Coronary Artery Disease: The Silent Killer

Coronary artery disease (CAD) is one of the most common illnesses that can cause a heart attack in people. It develops over years and has no clear signs and symptoms apart from a heart attack.

The illness begins due to a buildup of fats, cholesterol and other substances known as plaque in and on the artery walls.

Over time, this can cause narrowing or blockage of the coronary arteries and block the supply of oxygen-rich blood to heart which can lead chest pain (angina), shortness of breath and ultimately, heart attacks.

Typically, those above the age of 45, having a biological family member with heart disease, lack of sleep, smoking, consuming saturated fats along with other autoimmune diseases such as lupus and rheumatoid arthritis can increase the risk of developing CAD.

Nearly one in 10 Indian adults suffer from CAD and about two million people die from the disease annually. Apart from this, about 18 to 20 million American adults aged 20 and older are also affected about the disease.