Coronavirus FAQ: Answering the most frequently asked Covid-19 questions of 2020 - The Daily Guardian
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Answering the most frequently asked Covid-19 questions of 2020

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How serious is Covid-19?

Covid-19 is a highly infectious disease. However, a large proportion of those infected or tested positive either do not develop any symptom or have mild or moderate symptoms. Nearly all people with mild to moderate symptoms recover with supportive care. It can be serious or severe for high-risk populations such as the elderly and those with pre-existing health conditions. However, it is difficult to predict who can develop severe disease. Therefore, everyone should follow preventive measures.

Who is at risk of developing severe illness?

This is not possible to assess with certainty. However, the elderly and anyone with pre-existing health conditions (such as high blood pressure, heart disease, lung disease, cancer or diabetes) appear to develop serious illness more often than others. There is emerging scientific evidence that people with comorbidities are up to twelve times at higher risk of death due to Covid-19 and up to six times more likely to be hospitalised. Men in all age groups are at higher risk than women. Clearly, reducing comorbidities and improving one’s health is key to battling Covid-19. The experience of clinical settings in India indicates that people with two or more comorbidities in any combination, such as diabetes and kidney disease or hypertension and chronic lung disease, are at higher risk of serious diseases. In India, there are an estimated 55 million people with heart diseases and 70 million people with diabetes, which makes all of them high-risk.

Are men at higher risk in comparison to women and if yes, why?

The epidemiological data on Covid-19 cases from different parts of the world as well as India has shown that proportionately more men have tested positive for Covid-19 than women. Of all the Covid-19 deaths in India, 70 per cent of the deaths have been in men. This indicates that men are at a higher risk of suffering from moderate to severe disease. The reasons are not fully understood, and knowledge is evolving. Most likely, it is due to the way in which the immune system of men and women reacts. Researchers have found that in Covid-19, the immune response of men is mostly through cytokines and chemokine (the protective chemicals released by the immune system). The cytokine-based response, while being protective, can be harmful in excess, and results in severe disease, a phenomenon more commonly seen in men. In women, the immune response against Covid-19 is predominantly driven by T-cells. The T-cell-dependent response is more balanced and nuanced. There is more evidence emerging that oestrogen (a hormone in women) may have some protective role against the moderate to severe disease.

There is recent evidence that there could be a post-Covid-19 syndrome in children. How serious is this?

This is still being evaluated. It has been reported from multiple places in the US and is seen in individuals who sort of recovered and then they have a fever, hyper-inflammatory syndrome which affects the skin, intestines, and also results in cardiac dysfunction. Many of these patients require ICU care to support blood pressure. This is a syndrome that has been called multisystem inflammatory syndrome in children (MIS-C) and a case definition has been developed. This is a new disease and knowledge is still evolving. It mimics another similar childhood disease known as the Kawasaki disease.

Can a person be reinfected with Covid-19?

There are not many reports that we can classically categorize under reinfection as of now. To classify any case as reinfection, the genomic sequence of the virus from both episodes should be conducted. There have been only a few such cases of reinfections verified based on genomic sequence out of the 45 million cases reported till the end of October 2020. Based on this information, it is too early to make any conclusive reference. As the pandemic progresses and more and more people recover we may come to know how much of a problem reinfection is.

Does air pollution increase the chance of Covid-19 infection?

There have been studies which have indicated that increased air pollution or PM2.5 level is associated with increase in the morbidity and mortality by 10–17 per cent.2 Pollution causes airway inflammation and predisposes one to infection. More specifically, increase in air pollution results in higher number of cases of chronic respiratory and cardiac diseases such as asthma and chronic bronchitis. These conditions already burden the respiratory and cardiac system of an individual. Thereafter, if a person get Covid-19 infection, it is likely that the already burdened immune system and the inflammation caused by pollution in the system of that individual may not be able to fully handle the disease. Therefore, air pollution is likely to affect the moderate to severe cases of the disease. Studies have reported that the mitigation of air pollution can reduce Covid-19 mortality but can also help in reducing the future mortality.

I keep hearing about mutation in SARS-CoV-2. What does it mean for the severity of disease?

The mutation is a minor change in viral genomic sequence. All viruses mutate which helps them to adapt to continue to infect the human host. SARS-CoV-2 is fairly stable, yet there have been around 15,000 mutations which have been reported till September 2020. But most of these mutations have been in non-significant section of the viruses. There is no evidence that mutations in the various parts of SARS-CoV-2 would alter its ability to cause disease. Current evidence also does not suggest that any significant mutation has occurred to make the vaccines being developed ineffective.

What do we know about the risk of transmission from a confined space?

The study in the journal Science had found that people using long-distance or long-duration shared transport had a high risk of transmission. In fact, this risk was found to be higher than the risk of transmission to those living in the same household. These findings have implications on the use of long-distance mode of travel such as buses and trains.

Are there things I should not do to protect myself from Covid-19?

The key is to follow CABs at all times. A few harmful behaviours like the following should ideally be avoided:

• Smoking (it is the best time to quit smoking).

• Wearing multiple masks (handling of these masks can be challenging and put you at additional risk).

• Taking antibiotics (this is a viral infection, antibiotics do not work).

Is there any special protocol to follow for washing fruits and vegetables?

Wash them thoroughly as you would do otherwise, with clean water. Do not use detergent or other harmful materials on fruits and vegetables. Wash your hands properly after washing fruits and vegetables and avoid touching your face while washing fruits and vegetables.

Can I catch Covid-19 from my pet?

It is a disease transmitted from human-to-human through droplet infection as well as through surface contact. Though there have been a few cases of transmission reported from domestic animals to humans, the details on additional factors are not available for those settings. Studies have found that cats and dogs can get the virus from human beings. Researchers have cautioned against the over-interpretation of these findings. As of now, limited evidence suggests that animals do not contribute to wider spread of infection.

Can Covid-19 be transmitted by houseflies and mosquitoes?

There is no evidence that Covid-19 can be transmitted through houseflies and mosquitoes.

Can Covid-19 spread from shoes?

Evidence available till now indicates that the likelihood of Covid-19 being spread through shoes and then infecting others is low. As a precautionary measure, families with infants and young children should store shoes where children cannot reach them.

Can Covid-19 spread from food? How safe is food ordered from outside?

There is currently no confirmed case of Covid-19 transmitted through food or food packaging. Packaged food and food items are unlikely to transmit the virus. There is no evidence to suggest that Covid-19 is transmitted through food and water. However, considering that the containers we use may hold and transmit the virus to others, it is essential that we remain cautious. Anyone with suspected symptoms like cough and cold should avoid cooking food for others. One should properly clean the surface of the packaged food as a precaution.

Is it safe to receive a courier package?

Yes. Evidence says that the likelihood of an infected person contaminating commercial goods is low. The risk of catching Covid-19 from a package that has moved through, travelled and been exposed to different conditions and temperatures is low. The outer surface of the package should be properly cleaned.

Should one shower after returning from every public place, mall or a hospital?

It is not necessary to shower every time after returning from public places. However, this should be looked at on a case-to-case basis and the risk one poses to family members. If there are high-risk members, it may help to change clothes and take a shower. Every visit to the hospital does not mandate a shower on return but it can be done as a precautionary measure. However, healthcare workers who spend long hours in hospital and potential cases may consider changing clothes and taking a shower on return.

Excerpts from the book, ‘Till We Win’ (Penguin). Dr Chandrakant Lahariya is a medical doctor and leading public policy and health systems expert. Dr Gagandeep Kang is a noted infectious-disease researcher. Dr Randeep Guleria is director of the All India Institute of Medical Sciences, New Delhi. The authors have made an attempt to cite the most updated and reliable sources including peer-reviewed medical journals.

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No health worries for children born to mothers given seasonal flu vaccine in pregnancy

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Correspondent,Ottawa

A population-based study, published in the Journal of the American Medical Association (JAMA), has found flu vaccination during pregnancy does not lead to an increased risk of adverse early childhood health outcomes.

Although pregnant people are not more susceptible to acquiring influenza infection, they are at an increased risk of severe illness and complications if they get the flu during pregnancy. For this reason, all pregnant people are advised to receive a flu shot each year, yet only 36% received it according to a study monitoring four flu seasons in Nova Scotia. Safety concerns are reportedly a leading reason women may not receive influenza vaccination in pregnancy.

Dr Deshayne Fell, an Associate Professor of Epidemiology in the Faculty of Medicine at the University of Ottawa and a Scientist at the CHEO Research Institute, a pediatric healthcare and research centre, led the study along with researchers in Ontario and at Dalhousie University in Nova Scotia. The study followed over 28,000 children from birth up to an average age of 3.5 years, with the results suggesting that maternal influenza vaccination during pregnancy was not associated with:

– Immune-related health conditions, such as asthma, ear infections or other types of infection.

– Non-immune-related health problems like neoplasms, sensory impairment.

– Nonspecific health needs such as Emergency Department visits and hospitalisations did not increase.

“This study adds to what we know from other recent studies showing no harmful effects of flu vaccination during pregnancy on the long-term health of children,” says Dr Fell, whose other recent work includes studying the effectiveness and safety of Covid-19 vaccines during pregnancy.

She added, “This is important because we know that getting the flu shot during pregnancy not only protects the pregnant person but has the added bonus of protecting newborn babies from getting the flu during their first few months of life, which is when they are most susceptible to respiratory infections but still too young to get the flu shot themselves.”

The study, Association of Maternal Influenza Vaccination During Pregnancy with Early Childhood Health Outcomes, is published in JAMA.

With ANI inputs

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ALL YOU NEED TO KNOW ABOUT ALLERGIC SINUS INFECTIONS

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The incidence of Allergyis in 25% to 30% of the Indian population. Allergy can affect any geographical area. It involves primarily the younger population, affecting any age group. Men and women can both get affected almost equally by allergies. It is a type 1 hypersensitive reaction where eosinophil and IgE levels are raised. Asthma is the involvement of the lower respiratory tract. Allergic Rhinitis and Sinusitis is the involvement of the nose and sinuses. The nose being the main door to the respiratory system bears the brunt of allergic insult. Allergic Rhinitis is broadly classified into intermittent and persistent based on the duration of symptoms and mild, moderate or severe based on affecting working efficiency. The persistent and moderate to severe form of AR causes considerable morbidity by affecting working efficiency, sleep pattern, and school activities in the patients, especially in a young child or an adult of productive age. AR is caused by many aeroallergens (like tree, weed, and grass pollen), cat, dog, house dust mite (HDM), and moulds. HDM is the most common indoor allergen causing a persistent form of AR. 

The symptoms usually appear on exposure to the causative allergens and triggers. Excessive sneezing, recurrent nasal discharge, and nasal obstruction are the main symptoms of AR. Itching, hearing impairment, facial heaviness, and smell disturbances are the other symptoms. AR is generally undertreated and is neglected to an extent causing the disease to flood into surrounding structures like conjunctiva, sinuses, ear and then to the lower airways. Asthma is the condition when allergens reach the lower airways where symptoms are episodic cough, chest tightness, wheeze, and breathlessness. 

Skin prick allergen testing is the test of diagnosis but the detailed clinical history is quite revealing of the cause of symptoms. The raised eosinophils and immunoglobulin E is seen in the haematological and nasal fluid examination. Nasal endoscopy by ENT doctor reveal pale, swollen mucosa with rugosity and it will be boggy nasal septum and nasal turbinates. The hypertrophy of inferior turbinate is commonly stated by the patients as, “Naak me mass badh gaya hai”. The poorly handled disease can show polypoidal tissue in the nasal cavity. 

AR is a medical condition. Allergen avoidance and lifestyle modification are the commonly asked measures advised to the patients. Pet and food allergy is best managed by avoiding them. Pollen allergy is diagnosed by symptoms in particular season and it is managed by avoiding unnecessary outdoor activities, especially in early mornings and later in the evenings during the season. While going out, wearing a face mask can provide protection. The bedroom windows should be closed, preferably at night and morning hours. The correction of seepage and fungus infested corners and crevices, keeping the indoor environment clean and well ventilated are helpful methods in reducing fungal spore allergy. The presence of allergic symptoms while sleeping and cleaning the wardrobe is the indicator of HDM allergy. Corners, crevices must be cleaned properly. Regular hot sunlight exposure of pillows and mattresses and dust removal can be helpful. The cleaning of mattresses and pillows is possible with vacuum cleaner also. Regular changing of linens, use of synthetic covers over mattresses and pillows are the other measures to control HDM allergy. The deficiency of Vitamin D and Vitamin B12 predispose us to many diseases including allergy. The prevalence of Vitamin D deficiency is in 70% to 100% of the Indian population, according to hospital-based studies. The supplementation of vitamins is helpful in the control or elimination of allergy in selected cases. Regular physical activity and nasal douches (Jal Neti) help reduce allergy. Nasal douches can be done with a commercially available mixture or homemade mixture (mix baking soda and salt in water and flush the prepared liquid in the nasal cavity with a syringe).  Steroid based nasal sprays are the first line of medical management. The common myth regarding steroid spray is their side effects but medical literature is not reflecting the same. Steroid nasal sprays can be prescribed above two years of age. The other commonly employed pharmacotherapy are antihistamines, decongestant nasal drops, or spray. The patients show good and immediate response with nasal decongestants but it should be used for over seven days as it can revert the symptoms by the rebound effect of the drug. The prolonged use of nasal decongestants can induce systemic hypertension. Allergen immunotherapy involves the administration of a progressively increasing amount of an allergen perorally or subcutaneously reaching a dose that is effective in ameliorating the symptoms associated with subsequent exposure to the causative allergens. The selection of allergen is decided based on a skin prick test. Surgery has a very limited role in selected cases. Surgery is focused on the correction of persistent structural abnormality. 

AR is an autoimmune disease. A single course of treatment is generally not sufficient enough to control the disease. The course of medical treatment depends on the severity of the disease and it can be reduced significantly by lifestyle modification and allergen avoidance.

The writer is an Associate Professor, Department of ENT, AIIMS, New Delhi.

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No health worries for children born to mothers given seasonal flu vaccine in pregnancy

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Vaccine

A population-based study, published in the Journal of the American Medical Association (JAMA), has found flu vaccination during pregnancy does not lead to an increased risk of adverse early childhood health outcomes.

Although pregnant people are not more susceptible to acquiring influenza infection, they are at an increased risk of severe illness and complications if they get the flu during pregnancy. For this reason, all pregnant people are advised to receive a flu shot each year, yet only 36% received it according to a study monitoring four flu seasons in Nova Scotia. Safety concerns are reportedly a leading reason women may not receive influenza vaccination in pregnancy.

Dr Deshayne Fell, an Associate Professor of Epidemiology in the Faculty of Medicine at the University of Ottawa and a Scientist at the CHEO Research Institute, a pediatric healthcare and research centre, led the study along with researchers in Ontario and at Dalhousie University in Nova Scotia. The study followed over 28,000 children from birth up to an average age of 3.5 years, with the results suggesting that maternal influenza vaccination during pregnancy was not associated with:

– Immune-related health conditions, such as asthma, ear infections or other types of infection.

– Non-immune-related health problems like neoplasms, sensory impairment.

– Nonspecific health needs such as Emergency Department visits and hospitalisations did not increase.

“This study adds to what we know from other recent studies showing no harmful effects of flu vaccination during pregnancy on the long-term health of children,” says Dr Fell, whose other recent work includes studying the effectiveness and safety of Covid-19 vaccines during pregnancy.

She added, “This is important because we know that getting the flu shot during pregnancy not only protects the pregnant person but has the added bonus of protecting newborn babies from getting the flu during their first few months of life, which is when they are most susceptible to respiratory infections but still too young to get the flu shot themselves.”

The study, Association of Maternal Influenza Vaccination During Pregnancy with Early Childhood Health Outcomes, is published in JAMA.

This study adds to what we know from other recent studies showing no harmful effects of flu vaccination during pregnancy on the long-term health of children.

With ANI inputs

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ALL YOU NEED TO KNOW ABOUT ALLERGIC SINUS INFECTIONS

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The incidence of Allergyis in 25% to 30% of the Indian population. Allergy can affect any geographical area. It involves primarily the younger population, affecting any age group. Men and women can both get affected almost equally by allergies. It is a type 1 hypersensitive reaction where eosinophil and IgE levels are raised. Asthma is the involvement of the lower respiratory tract. Allergic Rhinitis and Sinusitis is the involvement of the nose and sinuses. The nose being the main door to the respiratory system bears the brunt of allergic insult. Allergic Rhinitis is broadly classified into intermittent and persistent based on the duration of symptoms and mild, moderate or severe based on affecting working efficiency. The persistent and moderate to severe form of AR causes considerable morbidity by affecting working efficiency, sleep pattern, and school activities in the patients, especially in a young child or an adult of productive age. AR is caused by many aeroallergens (like tree, weed, and grass pollen), cat, dog, house dust mite (HDM), and moulds. HDM is the most common indoor allergen causing a persistent form of AR. 

The symptoms usually appear on exposure to the causative allergens and triggers. Excessive sneezing, recurrent nasal discharge, and nasal obstruction are the main symptoms of AR. Itching, hearing impairment, facial heaviness, and smell disturbances are the other symptoms. AR is generally undertreated and is neglected to an extent causing the disease to flood into surrounding structures like conjunctiva, sinuses, ear and then to the lower airways. Asthma is the condition when allergens reach the lower airways where symptoms are episodic cough, chest tightness, wheeze, and breathlessness. 

Skin prick allergen testing is the test of diagnosis but the detailed clinical history is quite revealing of the cause of symptoms. The raised eosinophils and immunoglobulin E is seen in the haematological and nasal fluid examination. Nasal endoscopy by ENT doctor reveal pale, swollen mucosa with rugosity and it will be boggy nasal septum and nasal turbinates. The hypertrophy of inferior turbinate is commonly stated by the patients as, “Naak me mass badh gaya hai”. The poorly handled disease can show polypoidal tissue in the nasal cavity. 

AR is a medical condition. Allergen avoidance and lifestyle modification are the commonly asked measures advised to the patients. Pet and food allergy is best managed by avoiding them. Pollen allergy is diagnosed by symptoms in particular season and it is managed by avoiding unnecessary outdoor activities, especially in early mornings and later in the evenings during the season. While going out, wearing a face mask can provide protection. The bedroom windows should be closed, preferably at night and morning hours. The correction of seepage and fungus infested corners and crevices, keeping the indoor environment clean and well ventilated are helpful methods in reducing fungal spore allergy. The presence of allergic symptoms while sleeping and cleaning the wardrobe is the indicator of HDM allergy. Corners, crevices must be cleaned properly. Regular hot sunlight exposure of pillows and mattresses and dust removal can be helpful. The cleaning of mattresses and pillows is possible with vacuum cleaner also. Regular changing of linens, use of synthetic covers over mattresses and pillows are the other measures to control HDM allergy. The deficiency of Vitamin D and Vitamin B12 predispose us to many diseases including allergy. The prevalence of Vitamin D deficiency is in 70% to 100% of the Indian population, according to hospital-based studies. The supplementation of vitamins is helpful in the control or elimination of allergy in selected cases. Regular physical activity and nasal douches (Jal Neti) help reduce allergy. Nasal douches can be done with a commercially available mixture or homemade mixture (mix baking soda and salt in water and flush the prepared liquid in the nasal cavity with a syringe).  Steroid based nasal sprays are the first line of medical management. The common myth regarding steroid spray is their side effects but medical literature is not reflecting the same. Steroid nasal sprays can be prescribed above two years of age. The other commonly employed pharmacotherapy are antihistamines, decongestant nasal drops, or spray. The patients show good and immediate response with nasal decongestants but it should be used for over seven days as it can revert the symptoms by the rebound effect of the drug. The prolonged use of nasal decongestants can induce systemic hypertension. Allergen immunotherapy involves the administration of a progressively increasing amount of an allergen perorally or subcutaneously reaching a dose that is effective in ameliorating the symptoms associated with subsequent exposure to the causative allergens. The selection of allergen is decided based on a skin prick test. Surgery has a very limited role in selected cases. Surgery is focused on the correction of persistent structural abnormality. 

AR is an autoimmune disease. A single course of treatment is generally not sufficient enough to control the disease. The course of medical treatment depends on the severity of the disease and it can be reduced significantly by lifestyle modification and allergen avoidance.

The writer is an Associate Professor, Department of ENT, AIIMS, New Delhi.

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IT’S CRUCIAL TO MONITOR CASES, AND IF THEY GO BEYOND 5%, RESTRICTIONS MUST BE IMPLEMENTED: DR NAVEET WIG

Dr Naveet Wig, chairman of AIIMS Covid Task Force, exclusively spoke to us about the need to follow Covid guidelines, the reason behind the wastage of vaccines, how long the pandemic will last, and more.

AJEET SRIVASTAVA

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Q. How do you evaluate Unlock 2?

A. It’s a time of self-evaluation. The number of cases is still more than a lakh and the situation is grave. Unlock will only make the situation worse, and nothing will improve in this manner. I understand the economy is crucial but life is foremost. 

Q. We are witnessing massive crowding in markets. What precautions will you suggest for everyone?

A. The pandemic has taught so much to people like basic hygiene manners. A country like India is implementing social distancing; it was far stretched but now turning into reality. But still, when government eases the situation a little bit, people violate all the basic guidelines and that is terrible. People must wear a mask all the time, especially when they go out. The situation will get really bad if basic guidelines won’t be followed and the condition will be grave. It is important to understand that crowding and working in full strength will make things worse. So, people must decide voluntarily to work in half strength and maintain social distancing. 

Q. What are the basic things to follow to curb the spread of the virus?

A. Wearing a mask is foremost and forever. Working in half-strength is important. Don’t let your guards down. It’s important to monitor cases, and if it goes beyond 5% then restrictions must be implemented. Last time we waited till 20% to 25% and then considered implementing lockdown. We need to make proper arrangements in hospitals, sanitisation work and must keep the environment clean. 

Q. We are witnessing fear in society. Till when the situation will be like this? 

A. As per my study, 98% of infected people will recover but 2% to 3% will need ICU. We need to keep our locality, district, and society safe, and then the whole country will be safe. 

Representatives at the ground level will need to understand that it’s our and their responsibility to keep society safe by following basic Covid protocols. 

Q. How many active cases ring the alarm bell?

A. According to me, 5% is the threshold when the alarm bell must ring. For example, if 1,000 people are being tested and 50 are Covid positive then it is 5% of people infected and such patients need ICU bed and home isolation. Even the situation now is alarming and we must not take it lightly. 

Q. Many doctors have speculated that those who have recovered from Covid need no vaccination, how true is it?

A. The ones who never got infected are more prone to the virus compared to those who have recovered.  Covid recovered people should get vaccinated after three months.

Q. Centre is giving vaccines to states for free. How much the states need to stay careful to control Covid spread?

A. We need to have faith in the government. They are the only source of vaccines for us. Their distribution so far has been better but it needs to be more fluent. 

Q. We have witnessed wastage of vaccines too. What is the reason behind this?

A. We all need to stay united. There should be no space for blame-game. The wastage of vaccines is very unfortunate. We must ensure that everyone who is eligible and needs it must get vaccinated as early as possible. The vaccine will save you from dying and keep your immunity strong. You may feel feverish for a while but later on, it will be fine. 

Q. What will be your message to people?

A. You need to give two months for the vaccine to show effects. But nothing can ensure that a person will not get infected again. You need to wear a mask and maintain social distancing to stay safe. 

Q. Do you think we will have to wear a mask forever?

A. There is no reason to panic. As more people will be vaccinated, the situation and the immunity of citizens will improve. Researchers are working and they will improve the efficacy of the vaccine and that will eventually improve our health. 

Q. Will coronavirus behave like Swine Flue?

A. Predictions will make thing worse. So, we should act as per the behaviour of the virus. Wearing a mask, social distancing, and vaccination will only help us. 

Q. How long this will last?

A. Maybe two to five years. We need to keep our positive rates less and the rate of vaccination higher. We need to improve the vaccination process and may need immunity booster, and cocktail doses that will improve immunity for five to six years. 

Q. When will the country be Covid free. 

A. We need to take responsibility and accountability. With utmost sense and understanding, we will be able to overcome it.

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SECONDARY INFECTIONS INFLAME THE BRAIN, WORSENING COGNITION IN ALZHEIMER’S: STUDY

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A new research into Alzheimer’s disease (AD) suggested that secondary infections and new inflammatory events amplify the brain’s immune response and affect memory in mice and in humans – even when these secondary events occur outside the brain.

The study was published in Alzheimer’s and Dementia, the journal of the Alzheimer’s Association. Scientists believe that key brain cells (astrocytes and microglia) are already in an active state due to inflammation caused by AD and this new research shows that secondary infections can then trigger an over-the-top response in those cells, which has knock-on effects on brain rhythms and on cognition.

In the study, mice engineered to show features of AD were exposed to acute inflammatory events to observe the downstream effects on brain inflammation, neuronal network function and memory.

These mice showed new shifts in the output of astrocytes and microglia and displayed new cognitive impairment and disturbed ‘brain rhythms’ that did not occur in healthy, age-matched, mice. These new-onset cognitive changes are similar to acute and distressing psychiatric disturbances like delirium, which frequently occur in elderly patients.

Although it is difficult to replicate these findings in patients, the study additionally showed that AD patients who died with acute systemic infection showed heightened brain levels of IL-1b – a pro-inflammatory molecule that was important in causing the heightened immune response and the new-onset disruptions seen in the AD mice.

Colm Cunningham, Associate Professor in Trinity’s School of Biochemistry and Immunology, and the Trinity Biomedical Sciences Institute led the research.

He said, “Alzheimer’s disease is the most common form of dementia, affecting more than 5 per cent of those over 60 and this distressing, debilitating condition causes difficulties for a huge number of people across the globe. The more we know about the disease and its progression the better chance we have of treating those living with it. We believe our work adds to this knowledge base in a few ways. Primarily, we show that the Alzheimer’s-affected brain has a greater vulnerability to acute inflammatory events, even if they occur outside the brain.”

Cunningham added, “Placing this within the context of the slowly evolving progression of AD, we propose that these hypersensitive responses, now seen in multiple cell populations, may contribute to the negative outcomes that follow acute illness in older patients, including episodes of delirium and the accelerated cognitive trajectory that has been observed in patients who experience delirium before or during their dementia.”

The research was supported by the US National Institutes of Health (NIH) and by the Wellcome Trust.

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