The COVID-19 pandemic may be over, but our immune systems are still feeling the impact. After years of battling constant viral threats, from COVID-19 to seasonal flu and other infections, our body’s defense system is exhausted. Many people continue to experience lingering inflammation, frequent illnesses, and slower recovery times. This extended state of immune stress has compromised us further to chronic illness, including autoimmune diseases and even neurodegenerative diseases such as Parkinson's. So why is our immune system still in trouble? And how do we give it its power back? Understanding immune exhaustion is the beginning of rebuilding our body's natural immunity.

A weakened immune system makes people more susceptible to disease, mental illnesses, and even sleep disorders. Now, new research indicates that immune system depletion may play an important role in the onset of Parkinson's disease, a degenerative neurologic disorder that compromises movement and cognition.

Role of Inflammation in Parkinson's Disease

Dysfunctional immune response is a leading cause of long-standing inflammation within the body, that has been found to contribute towards a multitude of conditions, including cardiovascular conditions, diabetes, depression, and neurodegenerative diseases such as Alzheimer's.

As people age, their immune system naturally becomes less effective. This deterioration, referred to as immune exhaustion, may be a key contributor to the onset and progression of Parkinson’s disease. Rebecca Wallings, a Parkinson’s Foundation Launch Award grant recipient and senior postdoctoral fellow at the University of Florida, believes that an accumulation of exhausted immune cells could be driving neurodegeneration in Parkinson’s patients.

How a Tired Immune System Might Affect Parkinson's?

Parkinson's disease is most commonly linked with the degeneration and loss of dopaminergic neurons—motor nerve cells that produce dopamine, an essential neurotransmitter for movement. While researchers have long suspected inflammation is involved in this neurodegeneration, the mechanisms are not yet well understood.

Wallings' study is on immune cell exhaustion, a process by which aging immune cells fail to control immune responses effectively. Her research indicates that instead of dampening inflammation in Parkinson's patients, attempts should be made to rejuvenate the immune system to regain its functionality.

Energy Deficiency in Immune Cells

One of the major findings of Wallings' work is the function of mitochondrial impairment in immune cell exhaustion. Mitochondria are commonly called the powerhouses of cells, as they are vital for generating energy. As mitochondria age and become inefficient, immune cells fail to function well, potentially accelerating neurodegeneration in Parkinson's disease.

Wallings has found that mutations in the LRRK2 gene, a recognized genetic risk factor for Parkinson's disease, are linked with defective mitochondrial function and immune cell exhaustion. Her current work includes testing various therapeutic approaches to restore mitochondrial function in immune cells with the potential to enhance the immune system and potentially prevent or treat Parkinson's disease.

Will Rejuvenating the Immune System Help in Treatment?

For decades, the standard practice in treating Parkinson's has been to suppress brain inflammation. Yet Wallings' work indicates that instead of slowing down immune responses, restoring the immune system could be a more successful strategy. By addressing mitochondrial impairment and immune resilience, researchers can potentially reverse or slow down Parkinson's disease.

Wallings is now looking into how to rejuvenate immune cells by fixing mitochondria. She studies immune cells from patients with Parkinson's as well as from healthy subjects and performs experiments on animal models to determine if rejuvenation of the immune system could result in improved disease outcomes.

Lifestyle Factors That May Affect Parkinson's Risk

While there is no cure for Parkinson's disease, some lifestyle adjustments may decrease the chances of developing the illness. Since neurodegenerative diseases are associated with chronic inflammation and immune dysfunction, developing habits that enhance immune function might prove helpful.

Diet: There is evidence to suggest that eating in accordance with the Mediterranean or MIND diets, both high in antioxidants, healthy fats, and anti-inflammatory foods, can encourage brain wellness and reduce Parkinson's risk.

Avoiding Dangerous Substances: Restricting alcohol and nicotine use can maintain a robust immune system and suppress inflammation.

Reducing Stress: Chronic stress weakens immune function, so methods such as meditation, exercise, and sufficient sleep can lead to improved overall well-being.

Delhi’s air pollution has worsened even before the onset of peak winter. This has raised concerns about development and health of children who are constantly exposed to high levels of fine particulate matter (PM2.5).

While the immediate effects of polluted air like coughing, wheezing and breathing difficulties are known, research says that long-term exposure can also impact children’s developing brains, including effects on their memory, attention, IQ and ability to learn.

Delhi Winter Pollution Highest In 3 Years

On November 12, Delhi's air quality got listed under 'very poor' category. Stations like IIT Delhi and Delhi IITM recorded an AQI of 416, while NSUT Jaffarpur and Delhi DPCC recorded 404. Anand Vihar station recorded 319 while DTU Delhi stated 372.

A new analysis by the Centre for Science and Environment (CSE), released recently, found that Delhi’s average PM2.5 concentration during the week preceding Diwali stood at 236 micrograms per cubic metre (µg/m³), the highest in the last three years. This was 97% higher than the 120 µg/m³ recorded in 2025 and 32% above the 179 µg/m³ recorded in 2024.

The analysis also found that pollution levels during the early winter period were higher this year than in 2025. Vehicular emissions and pollution from neighbouring NCR districts were among the major contributors. The findings suggest that firecracker smoke from Diwali aggravated an already high pollution burden.

Delhi’s pollution crisis is not only threatening people’s lungs and cardiovascular health, it is also posing significant risks to children’s brain health. Could breathing polluted air affect how well children concentrate, recall information and learn at school?

Also read: World Pneumonia Day 2026: Post-Diwali Cough Or Pneumonia? Doctors Explain Warning Signs

Effects Of PM2.5 On Children’s Cognitive Health

PM2.5 refers to fine particulate matter with a diameter of 2.5 micrometres or smaller. These particles are small enough to travel deep into the respiratory system, fueling inflammation and oxidative stress. Not just lungs, their effects may reach children’s nervous systems.

Dr Sushil Singla, Director, Paediatrics, Sarvodaya Hospital, Sector 8, Faridabad told HealthandMe, “Exposure to PM2.5 (fine particulate matter) can affect children's cognitive development, including memory, attention span and learning abilities. These tiny particles can penetrate deep into the lungs and may trigger inflammation and oxidative stress, which can have wider effects on the developing brain. Children are particularly vulnerable because their brains are still developing and they inhale more air relative to their body weight than adults.”

The developing brain goes through significant changes throughout childhood. Processes involved in learning, memory, attention and executive function continue to evolve during these years. Exposure to environmental pollutants during fragile developmental periods is therefore a huge concern.

Also read: Delhi Air Pollution: PM2.5 Exposure May Raise Type 2 Diabetes Risk By 16%, Study Finds

Effects On Learning And Academic Performance

Difficulties in paying attention, memorising and processing complex information can make it harder for children to follow lessons in the classroom.

“Prolonged exposure to high levels of air pollution has been associated with difficulties in concentration, attention, information processing and memory. This may also affect a child's learning abilities and academic performance over time. Although the extent of the impact varies depending on the duration and intensity of exposure, parents should take preventive measures,” says Dr Singla.

What Does Science Say?

Also read: Delhi Breathes Toxic PM2.5: Study Finds 9 Million Lives Could Be Saved Globally By Meeting WHO Air Quality Limits

Several studies suggest that air pollution exposure may be associated with poorer cognitive outcomes in children.

A review and meta-analysis published in Environmental Health in 2024 examined six studies involving 4,860 children across North America, Europe and Asia. It found a statistically significant association between higher PM2.5 exposure and lower IQ scores. The researchers reported that every 1 µg/m³ increase in PM2.5 was associated with a 0.27-point decrease in full-scale IQ.

A 2022 review of 86 studies also found evidence between particulate matter exposure and poorer executive function in children, specifically working memory. Executive function refers to a set of mental skills that help children plan, focus attention, remember instructions and manage multiple tasks.

Recent research based on data from the US Adolescent Brain Cognitive Development (ABCD) study also showed that PM2.5 exposure was linked with smaller hippocampal volumes and lower working-memory in young people.

The hippocampus is a brain region involved in learning and memory. The researchers suggested that exposure during both prenatal development and late childhood could affect brain structure and function.

What Can Parents Do?

While individual precautions cannot eliminate the pollution burden, they can help reduce exposure. Dr Singla advises parents to monitor AQI levels, limit outdoor activities during peak pollution hours and ensure adequate indoor ventilation. Other measures include:

• Check air quality before outdoor activities: Avoid outdoor sports, running and strenuous exercise when pollution levels are high.

• Keep windows closed during pollution episodes: Ventilate rooms when outdoor air quality improves. Where possible, use an air purifier with a HEPA filter.

• Use a well-fitting N95 mask: A respirator can reduce exposure to particulate matter when children need to be outdoors.

• Follow school advisories: Parents should stay informed about changes to outdoor classes, sports and school schedules during severe pollution days.

Former US President Joe Biden has shared an update on his battle with stage 4 prostate cancer, saying the disease has sometimes slowed him down but has not stopped him.

In a post on X, ahead of the November 17 release of his memoir, PROMISE ME, AMERICA, Biden revealed that he was diagnosed with prostate cancer while writing the book.

“Some days are better than others. It hasn't stopped me. But sometimes it slows me down,” he wrote, adding that he would be unable to participate in as many book-related conversations as he had hoped.

Biden said his doctors were encouraged by his response to treatment. He also thanked people for their prayers and wishes, saying their support meant a great deal to him, Jill and their family.

Biden also discussed his cancer diagnosis, treatment and its impact on his life in an interview with People, alongside his wife, former First Lady Jill Biden.

Joe Biden: Would Have Resigned If He Had Known About Cancer

Also read: Over 40% Prostate Cancer Patients in India Diagnosed After Cancer Has Spread: ICMR study

Biden addressed speculation about when he learnt about his diagnosis, saying, “We let the public know when I found out.”

He said he initially experienced recurring pain, prompting Jill to question why men in their 70s were not routinely tested. Subsequent tests revealed that his prostate cancer had metastasised to the bone.

Biden also said he would have stepped down from the presidency had he known his discomfort was caused by cancer, People reported.

“If I had known that I was feeling lousy because I had cancer, I would have resigned,” he said, adding that he did not believe an 80-year-old man with cancer should be running for president.

The diagnosis changed the couple's plans for life after the White House, including travelling.

“Because of that metastasis, he will always have cancer,” Jill said. “It changes your life, it changes your perspective about life. So now we're on a new journey.”

Biden said he remained hopeful and was feeling good. He takes eight pills a day and has undergone two tests to check whether the cancer has spread further. He said the results indicated that it had not.

“I still have all my faculties. I still have my physical faculties as well. So we're hopeful,” he said.

Jill Biden On The Challenges Of Caregiving

Read More: Minimally Invasive Focal Therapy For Prostate Cancer Promises Fewer Side Effects Than Surgery Or Radiotherapy

Meanwhile, Jill described the emotional and physical demands of caring for her husband, saying it was different from looking after her parents or in-laws.

“It's just a lot different, I think, when it's your spouse because of the difference in the relationship,” she said.

Her daily routine now includes ensuring Biden eats well, exercises and takes his medication, as well as communicating with his doctors.

“I have seen how hard it is, how really emotionally hard it is, physically hard to go through each day,” she said.

The couple also discussed their family life and time with their grandchildren as they approach their 50th wedding anniversary.

What Is Prostate Cancer?

Prostate cancer develops in the prostate, a gland found only in males, located below the urinary bladder and in front of the rectum.

Nearly all prostate cancers develop from glandular cells and are classified as adenocarcinomas.

In 2020, an estimated 1.4 million new cases and 370,000 deaths from prostate cancer were reported worldwide. It was the most frequently diagnosed cancer among men in 112 countries and the leading cause of cancer deaths among men in 48 countries.

According to the US Centers for Disease Control and Prevention (CDC), 255,395 new prostate cancer cases were reported in the US in 2022, making it the most commonly diagnosed cancer among American men that year.

What Are The Symptoms Of Prostate Cancer?

Symptoms may include:

• Blood in the urine or semen
• Difficulty urinating
• Erectile dysfunction
• Bone pain
• Unexplained weight loss.

Young and older people are reporting persistent coughs and throat irritation following Diwali celebrations, with rising pollution levels, smog and exposure to firecracker emissions likely contributing to these symptoms.

However, when these symptoms persist or worsen, they could sometimes signal a more serious respiratory infection, including pneumonia, experts warned on World Pneumonia Day, observed every year on November 12.

Speaking to HealthandMe, Dr. Neelam H. Jain, Internal Medicine Specialist and Medical Educator at Apollo Hospitals, Bengaluru, said doctors' clinics tend to get swamped every November with patients who blame their lingering coughs entirely on post-Diwali smog.

"While particulate matter and fireworks residue certainly irritate airways, a cough that persists or worsens demands a closer look. Sometimes, what feels like seasonal irritation masks something more serious: pneumonia," she said.

The deterioration in air quality after Diwali can particularly affect children, older adults and people with pre-existing lung conditions.

"Exposure to elevated levels of particulate matter (PM2.5 and PM10), along with toxic gases from firecrackers and vehicular emissions, can irritate the respiratory tract, trigger inflammation and worsen existing respiratory illnesses," Dr. Vikas Mittal, Director and Pulmonologist at CK Birla Hospital, Delhi, told HealthandMe.

Also read: Delhi Pollution: Is Your Child's Cough Or Wheezing A Warning Sign? When Should Parents Worry?

What Are The Warning Signs Of Pneumonia?

Not every persistent cough indicates pneumonia. Exposure to firecracker emissions and poor air quality can cause airway irritation and inflammation. However, certain symptoms warrant medical attention.

Dr. Jain said a cough that changes from dry to producing thick, green or rust-coloured phlegm, particularly when accompanied by persistent fever, chills and sharp chest pain while breathing deeply, requires further evaluation.

"Pneumonia inflames the air sacs in one or both lungs, filling them with fluid or pus," she said.

Other symptoms that may indicate pneumonia include shortness of breath, fatigue and weakness. Older adults, children and people with underlying conditions such as asthma or chronic obstructive pulmonary disease (COPD) are particularly vulnerable to respiratory complications.

"If your post-Diwali cough lasts longer than two weeks, is accompanied by shortness of breath, or leaves you unusually fatigued, do not write it off as just bad air. Listen to your body and consult a doctor for an evaluation. Early diagnosis makes all the difference," Dr. Jain added.

People experiencing breathlessness, chest pain or high fever should seek medical attention without waiting for two weeks.

Can Air Pollution Increase The Risk Of Pneumonia?

Persistent cough, throat irritation, wheezing, breathlessness and chest tightness are common symptoms of pollution-induced respiratory irritation.

Dr. Mittal explained that air pollution does not directly cause pneumonia. However, it can impair the lungs' natural defence mechanisms, making people more susceptible to respiratory infections.

It can also aggravate conditions such as asthma, bronchitis and COPD, potentially increasing the risk of complications.

Read More: Dry Cough, Breathlessness May Not Always Be Asthma — Could It Be ILD?

How To Protect Your Lungs During High Pollution Levels

Delhi's overall Air Quality Index (AQI) rose to 319 on November 12, placing it in the 'very poor' category. As of 6:30 am, 36 of the city's 58 air quality monitoring stations recorded AQI readings above 300.

Dr. Mittal advised people to minimise outdoor exposure during periods of poor air quality and use well-fitted N95 masks when stepping outside.

Other precautions include:

• Keep indoor spaces adequately ventilated.
• Avoid strenuous outdoor activities when pollution levels are high.
• Stay adequately hydrated.
• Seek timely medical advice if respiratory symptoms persist or worsen.

What Is Pneumonia And How Can You Prevent It?

Pneumonia is an infection that causes inflammation in one or both lungs. It can be caused by bacteria, viruses or fungi. The infection causes the air sacs in the lungs, called alveoli, to fill with fluid or pus, making breathing difficult.

It can range from mild to life-threatening, particularly among young children, older adults and people with weakened immune systems. Some forms can also spread through respiratory droplets.

Measures to reduce the risk of pneumonia include:

• Vaccination: Get vaccinated against influenza, pneumococcal infections and COVID-19, as recommended by a healthcare professional.
• Good hygiene: Wash your hands regularly with soap and water to reduce the spread of germs.
• Healthy lifestyle: Maintain a balanced diet, exercise regularly and get adequate rest.
• Avoid smoking: Smoking can damage the lungs' natural defences against infections.