Cold sores are a common and often frustrating skin issue. While they may look like harmless blisters, cold sores are actually caused by the herpes simplex virus (HSV).

What Causes Cold Sores?

Cold sores are caused by the herpes simplex virus (HSV), which comes in two types: HSV-1 and HSV-2.

HSV-1 is the primary cause of cold sores, usually appearing around the mouth.

HSV-2 generally causes genital herpes but can also lead to cold sores.

While the appearance of cold sores caused by both HSV-1 and HSV-2 can look similar, their locations tend to differ. However, it is possible for HSV-1 to cause sores on the genitals and for HSV-2 to appear on the mouth.

How Do Cold Sores Spread?

Cold sores are highly contagious and can spread easily. The virus can be passed on through:

• Kissing or skin contact
• Sharing food, drinks, or cosmetics (such as lip balm)
• Oral sex, which can spread both cold sores and genital herpes

Even when a cold sore isn’t visible, the virus can still be spread through close contact. This makes prevention and management key to reducing outbreaks and the risk of infecting others.

Once someone contracts HSV, it stays in the body for life. While the virus remains dormant most of the time, it can reactivate and cause new sores, especially during periods of:

• Stress
• Illness
• A weakened immune system

Unfortunately, there’s no cure for the herpes virus, but the symptoms can be managed.

Symptoms of Cold Sores

Cold sores don’t just appear out of nowhere. Before the sore is visible, you may notice a tingling or burning sensation around the lips or face, which can occur several days before the sore forms. This is the best time to begin treatment to shorten the outbreak.

When a cold sore does appear, it often looks like a red, raised blister filled with fluid. The blister can be painful to touch, and there may be more than one. Cold sores usually last around two weeks and are contagious until they crust over and heal.

The Five Stages of a Cold Sore

Cold sores go through distinct stages as they develop and heal:

• Tingling and itching: You may feel these symptoms about 24 hours before the blister appears.
• Blisters: Small, fluid-filled blisters form, typically around the mouth.
• Bursting: The blisters burst and form painful sores.
• Scabbing: The sores dry out, scab over, and may itch or crack.
• Healing: The scab falls off, and the cold sore heals.

Risk Factors for Cold Sores

Certain factors can trigger the reactivation of HSV, leading to cold sores. These include:

• Infection, fever, or cold
• Sun exposure
• Stress
• Menstruation
• Dental work or injury
• Weakened immune system due to conditions like HIV/AIDS, eczema, or chemotherapy

Managing and Treating Cold Sores

There’s no cure for cold sores, but several treatments can ease the symptoms and help manage outbreaks.

Topical Ointments and Creams

Over-the-counter antiviral creams like docosanol (Abreva) or prescription ointments like penciclovir (Denavir) can help reduce the duration of an outbreak, especially if applied at the first sign of a cold sore.

Oral Medications

Prescription antiviral medications like acyclovir, valacyclovir, and famciclovir can also help, particularly for people who have frequent or severe outbreaks. Your doctor may recommend taking these medications regularly to prevent future outbreaks.

Home Remedies

There are also some home remedies that may provide relief, such as:

• Applying ice or a cold washcloth to the sore
• Using aloe vera gel or lemon balm lip balms
• Applying petroleum jelly to ease discomfort

Canker Sores vs. Cold Sores: What's the Difference?

While cold sores and canker sores may seem similar, they are quite different:

Cold sores are caused by the herpes virus, appear around the mouth, and are contagious.

Canker sores are not contagious and appear as ulcers inside the mouth or throat.

Preventing the Spread of Cold Sores

To avoid spreading cold sores:

• Wash your hands frequently
• Avoid close contact with others during an outbreak
• Don’t share food, drinks, or personal items like lip balm

Cold sores can be a persistent issue, but with proper care and management, you can reduce the frequency of outbreaks and prevent spreading the virus to others.

As summer heat intensifies both in India and globally, many people may experience unusual heart sensations such as a racing heartbeat, chest fluttering, skipped beats, or pounding sensations, even while resting.

Speaking to HealthandMe, Dr. L.K. Jha, Associate Director and Head Unit-II, Cardiology, Asian Hospital, Faridabad, said that heatwaves can significantly increase the risk of heart palpitations.

Normal healthy people may experience occasional mild palpitations due to heat exposure, which usually resolve with rest, fluids, and cooling off. However, experts warn that when palpitations are accompanied by symptoms such as chest pain, loss of consciousness, shortness of breath, extreme light-headedness, or recurring episodes while resting, they may indicate an underlying cardiac rhythm issue requiring medical attention.

“The association between heatwaves and palpitations occurs more frequently than people think,” Dr. Jha said.

Dehydration: A Key Risk Factor

The human body constantly works to maintain a stable internal temperature.

During extreme heat, blood vessels dilate to release heat through the skin, while the heart pumps faster to circulate blood and cool the body. According to Dr. Jha, this additional strain on the cardiovascular system can make the heartbeat feel stronger or irregular, especially in people sensitive to heat.

Also read: Heatwave In India: Temperatures Continuously Rising; Stay Hydrated, Says PM Modi

Dr. Jha explained that dehydration is one of the biggest contributors to heat-related palpitations.

Excessive sweating leads to the loss of water and essential electrolytes such as sodium, potassium, and magnesium, all of which are crucial for maintaining a normal heart rhythm.

“Dehydration can lower blood pressure, forcing the heart to beat faster, which may cause dizziness, shakiness, or pounding sensations,” he said.

Existing Health Conditions Can Increase Risk

Heatwaves may also worsen existing conditions such as anxiety, thyroid disorders, anemia, diabetes, and heart disease, increasing the likelihood of palpitations.

Certain medications, including blood pressure drugs, diuretics, asthma inhalers, as well as excessive consumption of caffeine or energy drinks, may further contribute to irregular heartbeats during hot weather, Dr. Jha told HealthandMe.

Sleep disturbances caused by hot nights can also trigger stress hormones in the body, potentially leading to rapid heartbeat episodes or fluttering sensations.

Also read: Climate Change Fueling Chikungunya Spread To Europe, North America, Warns Study

When To Seek Medical Help?

Dr. Jha noted that occasional mild palpitations due to heat exposure are common and often improve with rest, hydration, and cooling down.

Doctors recommend drinking fluids regularly, replenishing electrolytes through coconut water, buttermilk, lemon water, or Oral Rehydration Salts (ORS), avoiding prolonged sun exposure, and limiting caffeine and alcohol intake during heatwaves.

However, persistent or severe palpitations may indicate a more serious condition.

“If palpitations are accompanied by chest pain, shortness of breath, fainting, severe light-headedness, or repeated episodes while resting, immediate medical evaluation is necessary,” Dr. Jha warned.

He added that some heat-related palpitations may actually signal an underlying heart rhythm disorder requiring treatment.

Yellow Alert In Delhi; Heat Dome in Europe

Meanwhile, the India Meteorological Department (IMD) has issued a yellow alert for heatwave conditions in Delhi.

Heatwave conditions in the national capital are expected to continue till tomorrow, with maximum temperatures remaining between 44 and 46 degrees Celsius.

The IMD forecast also includes relief in the form of thunderstorms, dust storms, and light rainfall from May 28 evening onwards.

At the same time, European countries like France, the United Kingdom, Spain, and Germany are experiencing early heatwaves and record-breaking conditions.

The sweltering heat conditions have affected scores of people, reportedly resulting in the deaths of about seven people in France. The unusually high temperatures early in May are being triggered by a phenomenon called a “heat dome”.

As a result, southern and southwestern regions, including Portugal, Spain, and France, will experience daytime temperature highs of 38°C. The majority of France is under a moderate to high temperature warning, while Germany and the UK are witnessing maximum temperatures exceeding 30°C, the Euronews reported.

The human body thrives on essential metals, but excessive exposure can cause a variety of issues for them in the long run, and this very fact has come to light in a recent study done by a research team at the Icahn School of Medicine at Mount Sinai Hospital. The paper reveals the detrimental impact of getting exposed to toxic metals early in life.

Drs. Manish Arora, Elza Rechtman, and Megan Horton at the Icahn School of Medicine at Mount Sinai Hospital thoroughly studied the mental effects in infants after early exposure to toxic metals. The study was published in Science Advances.

The research team studied the teeth of 489 infants aged 8 to 14 years old. As teeth grow in layers, and each layer can provide data on metal exposure, the researchers measured exposure to lead, lithium, barium, copper, manganese, magnesium, tin, zinc, and strontium.

The study also monitored 395 children for symptoms relating to anxiety, depression, hyperactivity, and attention, and magnetic resonance imaging (MRI) was used to examine 191 children.

Metals like zinc, magnesium, and manganese are very important for growth and health, but overexposure to these metals in children can cause harm.

Childhood is the time for mental growth in children, but this is the same time span when they get exposed to toxic metals as well. From food to inhaling tobacco smoke or exposure through touch, there are many ways a child gets near those adversarial metals and causes harm to themselves.

The results of the study show that exposure to heavy metals mainly happens between 6 and 9 months after birth. They also claim that the excessive metal exposures during key periods of brain development can have long-lasting effects.

Also Read: How To Get Rid Of Heavy Metals In Your Body?

How To Detox From Heavy Metals?

Reducing exposure to heavy metals can be achieved through simple lifestyle and dietary changes. This includes switching to greener diets and replacing household products. High-quality fish can help minimize mercury ingestion, while cilantro, seaweed, and leafy greens are known to trap and remove toxins from the body. Aluminium-free deodorants and titanium-free makeup and toothpaste are also recommended.

For a more intensive detox, using high-quality supplements alongside drinking at least two litres of water daily can help flush heavy metals. Armistead explains that these supplements aid the body in moving heavy metals from cells to the lymphatic system, which then transports them into the bloodstream for filtration by the liver and kidneys. The toxins are ultimately excreted via urine or bowels.

Even as climate change is driving mosquitoes north, a new study warned that Europe and North America can be new hotspots for the chikungunya virus.

Alarmingly, the research indicated that 139 countries face risk, covering 21.26 per cent of global land area for chikungunya, a mosquito-borne viral disease.

Further, the findings published in the journal Frontiers in Cellular and Infection Microbiology suggest that climate-driven vector expansion has significantly broadened the geographic scope of the CHIKV threat.

Also Read: Meningitis Outbreak In Sri Lanka: 200 Reported Cases, Authorities Issued Special Guidelines

“We show that under climate change models, the virus will further expand northward into temperate regions, especially northeastern North America, central Europe, and East Asia,” said Dr Ye Xu, from Zhejiang Chinese Medical University, China.

Chikungunya is a viral illness transmitted to humans primarily through the bite of infected Aedes aegypti and Aedes albopictus mosquitoes.

How Climate Is Linked To Mosquito Behavior?

Also Read: Climate Change Fueled Rising Salmonella Drug Resistance Over Decades: The Lancet Study

As the primary vectors of chikungunya, Aedes aegypti and Aedes albopictus are highly influenced by climate conditions.

These mosquitoes thrive in warm and humid environments, with temperature playing a major role in their breeding, survival, and ability to spread the virus.

The rising temperatures can accelerate larval development, increase mosquito reproduction, and shorten the virus’s incubation period inside the mosquito, making transmission more efficient.

In the study, the researchers explained that stable temperature patterns and seasonal variations are especially important for Aedes aegypti. The species is highly sensitive to colder temperatures, with egg hatching rates dropping significantly at around 12°C. This limits how far the mosquito can spread into cooler regions.

However, climate change and warming temperatures are making previously unsuitable regions in Europe and North America more favorable for these mosquito species, raising concerns about the growing risk of chikungunya outbreaks, the team said.

“Because this mosquito can tolerate cooler conditions better than the yellow fever mosquito, warming may allow it to establish in places that used to be too cold,” said Dr Yang Wu, Guangzhou Customs Technology Center, China.

“When suitable mosquitoes become established, the chance of local chikungunya transmission increases.”

Global Chikungunya Cases

Read More: 16 Million Indians Die Due To Hypertension Every Year: AIIMS Doc

In 2025, there were 502,264 reported chikungunya cases globally, accounting for 186 deaths across 41 countries and territories, according to the Pan American Health Organization.

This disease burden is projected to escalate under climate change, which is profoundly altering the distribution patterns of infectious diseases, the researchers noted.

“The public does not need to panic, but health systems should prepare early,” warned Dr Xu.

The researchers recommended that these regions implement proactive entomological surveillance and adaptive public health infrastructure by 2040 to mitigate the threat of emerging arboviral epidemics.

Among the proposed measures, researchers include

• tracking mosquitoes,
• training healthcare workers to quickly recognise the virus,
• strengthening mosquito control,
• setting up rapid-response plans before outbreaks occur.

Chikungunya Symptoms You Should Know

Most symptoms are generally self-limiting and last for 2–3 days. The disease is characterized by

• an abrupt onset of fever,
• joint pain
• muscle pain,
• headache,
• nausea,
• fatigue
• rash.