Drastic fall in Covid-19 cases in India: Top health experts explain why - The Daily Guardian
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Drastic fall in Covid-19 cases in India: Top health experts explain why

Reaching saturation points, producing antibodies against the virus, and cross immunity due to the BCG vaccine may be contributing factors in the decrease in Covid-19 cases in the country right now, say Dr Satyajit Rath and Dr Lalit Kant.

Shalini Bhardwaj

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There was a time when India had been reporting close to 1,00,000 new Covid-19 cases each day and hospitals were overloaded with patients, but now the numbers have fallen drastically, to as low as 8,000 cases. However, the variant of the virus from South Africa is still a big concern and the pandemic has not come to its end by any means. Dr Satyajit Rath, immunologist and former professor at the National Institute of Immunology, and Dr Lalit Kant, former scientist and head of the Epidemiology and Communicable Diseases Division at ICMR, share their insights on the subject in an exclusive interview with The Daily Guardian. Excerpts:

Q: What can be the reason behind the declining number of Covid-19 cases in India? What is the mystery behind it?

Dr Satyajit Rath: Different countries have had different trajectories of the epidemic surging and receding; India’s is not particularly unique. I do not think that we reliably understand the reasons behind each specific pattern. That said, it is possible that the fastest rate of transmission in open-air countries such as India might be in heavily crowded urban working-class localities, and those may be saturated by now, leading to the currently relatively slow spread of the infection.

Dr Lalit Kant: There are many things which contribute to this. One thing is more people developing antibodies against the virus which gives them some kind of protection. I believe, in India, the proportion of cases is 20%- 80%, which means that severe cases are 20% and mild cases are 80%, in comparison to Western countries. In India, there are more cases of a milder infection or asymptomatic patients. The second reason (for the fall in cases) is that people in India spend more time outdoors, rather than indoors which has lesser air exchange. So, chances of the infection happening go down. There is also the composition of the age structure of the Indian population. Another reason can be the immunisation that we get here in the country, especially the BCG and measles vaccines. Wherever the BCG has been used, cases have been much less. So, there can be cross immunity, but all these things are still conjectured.

Q: What needs to be done if this virus mutates more? It is already happening in countries like South Africa and the UK.

Dr Satyajit Rath: All viruses mutate, especially RNA viruses like SARS-CoV-2 (or influenza, or HIV). They mutate everywhere, not simply in some countries. They do not actually mutate ‘more’ or ‘less; it is just that, since mutations happen in them along with growth, the more the growth of a virus, the more the mutations that accumulate. The greater the diversity of mutational changes in the virus population, the more the likelihood that some of those changes may be beneficial to the spread of the virus under prevailing conditions. That is likely why most of the virus variants that have emerged are better at spreading. As antibodies resulting from infection or vaccination become more and more common, variants that emerge will likely be resistant to such antibodies. At that point, new-generation vaccines will be needed. If we track the emergence of the mutations carefully, we will be in a good position to design such next-gen vaccines in good time.

Dr Lalit Kant: We had a system of testing people who are coming from other countries. A lot of countries have identified the South African strain. The South African strain appears to be more problematic as compared to the UK strain because some of the vaccines that underwent clinical trials against the South African strain found out that the efficacy levels dropped to just 55%. So, it’s important to monitor people who are coming from South Africa.

Q: Do you think we can face another viral pandemic in the future? What should be done to control such pandemics now?

Dr Satyajit Rath: Pandemics like this are natural phenomena. We have had them in the past, we will have them in the future. They are hard to predict specifically. We need to invest in tracking infectious diseases, in planning for vaccine manufacturing facilities for the public good, and in the careful provision of adequate public health facilities.

Dr Lalit Kant: Another pandemic will happen but we don’t know when it will happen and if it will be a respiratory infection. The government is stepping up towards controlling such pandemics with NIV labs, by increasing surveillance, investing in biotechnology and vaccines, etc. Each pandemic comes with its own challenges. So, we need to be prepared for such challenges.

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Medically Speaking

A new study suggests early weight loss protects fertility of obese persons

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The reproductive function in obese boys can be improved through weight loss, which in turn could protect their fertility in adulthood, according to new research.

The study presented at the 59th Annual European Society for Paediatric Endocrinology Meeting suggests that even after short-term weight loss, alterations in reproductive function could be partially reversed in young boys with obesity. This indicates that early management of obesity in childhood could help prevent future fertility problems in men. Childhood obesity can have some profound effects on future health in adulthood, including a greater risk of cancer, heart disease and type 2 diabetes. Obesity has also been linked to fertility problems in both men and women. The commonest causes of fertility problems in men are usually sperm abnormalities or a low sperm count.

Leydig cells in the testes become active in puberty to produce the main male hormone, testosterone. Sertoli cells in the testes are critical for the production of healthy sperm and produce several reproductive hormones, essential for sperm maturation.

Previous work has shown early alteration of Sertoli cell function in obese boys from the age of 12, with later alteration in Leydig cell function from the age of 14. However, whether weight loss might reverse the altered function of these cells had not been investigated.

In this study, Dr Solene Rerat and colleagues at Angers University Hospital in France investigated how a 12-week educational weight loss programme in 34 boys, aged 10-18 years, affected markers of Leydig and Sertoli cell function, as well as metabolism.

The boys had a healthy, balanced diet, undertook physical activity for at least one hour per day, according to international recommendations, and had weekly individual sessions with a dietician. Before and after the programme, levels of reproductive hormones, body fat composition and blood glucose were measured for comparison. Over the 12 weeks, the boys significantly lost weight and had improved insulin levels, as well as increased testosterone levels.

No significant changes were found in markers of Sertoli cell function. Since fat cells produce an enzyme that converts testosterone to oestrogen, the actual loss of fat mass may account for some of the increased testosterone levels, in addition to the reversal of Leydig cell altered function.

Dr Rerat states, “These findings underline the need to consider childhood obesity as a factor in future fertility issues. We strongly recommend that early management of childhood obesity is necessary to reverse these impairments, and to help prevent future reproductive problems, as well as lowering the risks of other debilitating diseases.”

The team now plans to measure the reproductive function of the group more long-term and to expand it to include more participants to gather more data to confirm and extend these findings.

Dr Rerat cautions, “Our study only evaluated the effects in a small number of obese boys after a twelve-week therapeutic educational program. Further studies with longer follow up are needed to help us fully study the effect of weight reduction on reproductive function.”

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Link between diet and mental health

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Lifestyle components like eating habits, exercise, sleep, and work patterns etc affect our well-being on a regular basis and many health problems both physical and mental, are associated with disbalance in our routine life.

There is no specific diet which treats psychiatric disorders but certain dietary choices and patterns are helpful in improving overall health as well as promote physical and mental stress tolerance which leads to better psychological health.

FOODS TO EAT

Among common diet plans, the Mediterranean diet has the strongest evidence supporting its ability to reduce the symptoms of depression.

Compounds in the Mediterranean diet that have links to lower depression rates include:

• omega-3 fatty acids

• vitamin D

• methylfolate

• s-adenosylmethionine

The Mediterranean diet consists of:

• plenty of fruits and vegetables

• whole grains

• potatoes

• cereals

• beans and pulses

• nuts and seeds

• olive oil

• low-to-moderate amounts of dairy products, fish, and poultry

• very little red meat

• eggs up to four times a week

• low-to-moderate amounts of wine to

FOODS TO AVOID

A 2010 study showed that women who ate unhealthful Western-style diets had more psychological symptoms. The foods that these participants were eating included:

• processed foods

• fried foods

• refined grains such as white bread

• sugary products

• beer

Similar unhealthful dietary patterns that typically lead to obesity, diabetes, and other physical health problems can also contribute to poor mental health.

The balanced Indian meal plans have necessary components for health and well being.

SUMMARY

• Eat a combination of locally grown products like whole grains, fruits and vegetables and limited amounts of unrefined fat like cold pressed mustard oil and desi ghee (clarified butter).

• Fish, nuts and seeds like walnuts, pistachios, almonds, flaxseeds and chia seeds have high amounts of omega3 fatty acids which are good for nerve health.

• Poultry, eggs and dairy products are rich in Vitamin B12 which is associated with nerve health and better stress tolerance.

• Balanced calorie intake with good nutritional components (complex carbohydrates, proteins, vitamins, minerals and healthy fatty acids) is the key to good health and weight management. Over eating and under eating both have negative effect on physical and mental well being.

• Regular eating patterns are helpful in maintaining stable sugar levels and boost energy.

• Water makes 60% of body. Drink plenty of plain water for good health.

• Good gut health is linked to balance of good bacteria in our intestines which are plenty in probiotic foods like curd, chaach, and fermented eatables like idli, dosa, and kimchi.

• Sodium is an essential nutrient that controls blood pressure. It is also needed to make nerves and muscles work properly. For this reason, patients need to consume the right amount. Many medicines reduce sodium levels which can lead to hyponatremia with significant nervous system problems. The AHA recommends no more than 2,300 milligrams a day, but patients should move toward an ideal limit of no more than 1,500 mg per day for most adults. Excessive salt comes from packaged and preserved food which in any case need to be avoided.

• Avoid alcohol and nicotine, they may appear to reduce stress but eventually lead to low stress tolerance and mood instability.

• Drugs like pot/weed/grass/opioids and other designer drugs increase vulnerability to major psychiatric disorders.

For specific metabolic disorders like diabetes, obesity, PCOD or inflammatory condition, please consult a dietitian.

The writer is a Senior Psychiatrist and Founder & Director of Manasthali.

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COVID-19 PANDEMIC EXACERBATES BURNOUT RATE IN DOCTORS

Doctors at the frontlines of the pandemic are facing extremely challenging working conditions. Long gruelling working hours, constant emergencies, witnessing a high death rate, and a persistent struggle to save lives not just cause physical exhaustion but also result in an emotional and mental turmoil.

Dr Shuchin Bajaj

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Long working hours, emergency calls, a never ending stream of patients and prolonged stress are factors that are common in the lives of doctors. In countries with a low doctor-patient ratio like India, doctors often experience overwhelming workload and excessive pressure. Factors such as lack of safety and vulnerability to violence further adds to this stress. Even before the coronavirus outbreak challenges healthcare providers like never before, physicians were experiencing a high rate of burnout. Several studies have pointed this out in recent years. A small but powerful indicative study published in the Indian Journal of Psychiatry in 2018 suggested that a significantly higher proportion of doctors in Indian setting experience stress, depression, and burnout. Out of the 445 responders in the study, 30.1% were found to have depression and 16.7% reported having suicidal thoughts. More than 90% of the participants reported some level of burnout.

The coronavirus outbreak has hugely magnified this problem, exacerbating the burnout rate in doctors and other healthcare staff particularly those involved in treating Covid-19 patients. Burnout is a condition where an individual experiences overwhelming mental and physical exhaustion owing to excessive stress. It not just affects the mental and physical health of the individual but also impacts his/her job related outcomes.

COVID-19 BURNOUT IN DOCTORS

In China, a cross-sectional study published in JAMA Network Open Journal in March 2020 found that the coronavirus outbreak had a devastating impact on the mental health of healthcare workers. Out of the 1257 respondents, 50.4% were found to have symptoms of depression, 34.0% reported insomnia, 44.6% reported symptoms of anxiety, and 71.5% reported distress. The researchers concluded that working in the frontline was an independent risk factor for worse mental health outcomes.

Doctors at the frontlines of the pandemic are facing extremely challenging working conditions. Long grueling working hours, constant emergencies, witnessing a high death rate, and a persistent struggle to save lives not just cause physical exhaustion but also result in an emotional and mental turmoil. In countries where severely ill patients exceeded the healthcare capacity to treat, doctors had to actually choose whom to treat and whom to let die. Absence of a clear treatment route is another major work challenge.

Wearing PPEs for long hours is itself a major challenge. Once your PPE is on your ability to eat, drink water or even go to the washroom is restricted. The grueling heat makes long hours of wearing PPEs worse. However, the most significant challenge is the threat from the disease itself. Being in the midst of patients every day puts doctors at a high risk of catching the infection themselves. By first week of May, over 500 doctors, nurses, and paramedics had already been infected by coronavirus in the country. An AIIMS doctors was applauded for putting himself at significant risk when he removed his goggles and face shield to be able to clearly see and re-intubate a seriously ill patient. This tells us how doctors are putting themselves at risk during this global pandemic. As doctors get infected and result in a further depletion of workforce, the remaining physicians face an even greater workload.

Apart from all the above concerns, one major concern for doctors and healthcare staff is the threat of carrying the infection to their home and families.

HOW TO ADDRESS THE BURNOUT CRISIS

As much as it is important to ensure the safety of doctors, it is equally important to help them address the mental and physical outcomes of burnout. Governments, healthcare providers, and hospitals must initiate a series of measures to help address this burnout crisis.

ADEQUATE AVAILABILITY OF PROTECTIVE EQUIPMENT

Strict adherence to properly wearing PPEs has been found to be effective in minimising infection rate among doctors and healthcare workers. It is extremely important therefore that governments and hospitals ensure adequate supply and sufficient availability of PPEs for doctors. Adequate supply of PPEs and addressing the shortage concerns also allays the mental stress and fear among doctors. It is also important to ensure that doctors do not have to wear the same protective equipment for more than 8-10 hours.

ACCESS TO COUNSELLING AND MENTAL HEALTH EXPERTS

The World Health Organisation has advised doctors to take extra care of their health by consuming healthy food, taking adequate rest, and staying active. The body has also recommended de-stressing and avoiding smoking or drugs. Hospitals must ensure that doctors have regular access to counseling support to advocate healthy living. They must also have access to mental health experts to give them a proper outlet for their mental and emotional turmoil.

OFFERING ALTERNATIVE STAY ARRANGEMENTS

Governments and private healthcare providers must also arrange for alternative accommodation for doctors and other healthcare staff members to allow them stay away from their families during the time they are treating Covid-19 patients. This takes off the extra pressure and concern about carrying the virus home.

REDUCE BURDEN BY ADDING TO THE MANPOWER

With the number of patients rising steeply every day, we need to find innovative ways to have sufficient backup resource of doctors. In this situation, it makes sense to train final year MBBS and PG medical students in critical care and keep them ready to be deployed in case the need arises.

The writer is Founder Director, Ujala Cygnus Group of Hospitals.

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Medically Speaking

Diet and Mental Health

Published

on

Lifestyle components like eating habits, exercise, sleep and work patterns etc affect our well-being on a regular basis and many health problems both physical and mental, are associated with dis balance in our routine life.

There is no specific diet which treats psychiatric disorders but certain dietary choices and patterns are helpful in improving overall health as well as promote physical and mental stress tolerance which leads to better psychological health.

Foods to eat-

Among common diet plans, the Mediterranean diet has the strongest evidence supporting its ability to reduce the symptoms of depression.

Compounds in the Mediterranean diet that have links to lower depression rates include:

                  •                omega-3 fatty acids

                  •                vitamin D

                  •                methylfolate

                  •                s-adenosylmethionine

The Mediterranean diet consists of:

                  •                plenty of fruits and vegetables

                  •                whole grains

                  •                potatoes

                  •                cereals

                  •                beans and pulses

                  •                nuts and seeds

                  •                olive oil

                  •                low-to-moderate amounts of dairy products, fish, and poultry

                  •                very little red meat

                  •                eggs up to four times a week

                  •                low-to-moderate amounts of wine

Foods to avoid-

A 2010 study showed that women who ate unhealthful Western-style diets had more psychological symptoms. The foods that these participants were eating included:

                  •                processed foods

                  •                fried foods

                  •                refined grains, such as white bread

                  •                sugary products

                  •                beer

Similar unhealthful dietary patterns that typically lead to obesity, diabetes, and other physical health problems can also contribute to poor mental health.

The balanced Indian meal plans have necessary components for health and well being.

Summary-

                  •                Eat a combination of locally grown products like whole grains, fruits and vegetables and limited amounts of un refined fat like cold pressed mustard oil and desi ghee ( clarified butter).

                  •                Fish, nuts and seeds like walnuts, pistachios, almonds, flaxseeds and chia seeds have high amounts of omega3 fatty acids which are good for nerve health.

                  •                Poultry, eggs and dairy products are rich in Vitamin B12 which is associated with nerve health and better stress tolerance.

                  •                Balanced calorie intake with good nutritional components (complex carbohydrates, proteins, vitamins, minerals and healthy fatty acids) is the key to good health and weight management. Over eating and under eating both have negative effect on physical and mental well being.

                  •                Regular eating patterns are helpful in maintaining stable sugar levels and boost energy.

                  •                Water makes 60% of body. Drink plenty of plain water for good health.

                  •                Good gut health is linked to balance of good bacteria in our intestines which are plenty in probiotic foods like curd, chaach and fermented eatables like idli, dosa and kimchi.

                  •                Sodium is an essential nutrient that controls blood pressure. It is also needed to make nerves and muscles work properly. For this reason, patients need to consume the right amount. Many medicines reduce sodium levels which can lead to hyponatremia with significant nervous system problems. The AHA recommends no more than 2,300 milligrams a day, but patients should move toward an ideal limit of no more than 1,500 mg per day for most adults. Excessive salt comes from packaged and preserved food which in any case need to be avoided.

                  •                Avoid alcohol and nicotine, they may appear to reduce stress but eventually lead to low stress tolerance and mood instability.

                  •                Drugs like pot/weed/grass/opioids and other designer drugs increase vulnerability to major psychiatric disorders.

For specific metabolic disorders like Diabetes, Obesity, PCOD or inflammatory condition, please consult a dietitian.

Continue Reading

Medically Speaking

COVID 19 exacerbates burnout rate in doctors: How to address this crisis

Dr Shuchin Bajaj

Published

on

Long working hours, emergency calls, a never ending stream of patients and prolonged stress are factors that are common in the lives of doctors. In countries with a low doctor-patient ratio like India, doctors often experience overwhelming workload and excessive pressure. Factors such as lack of safety and vulnerability to violence further adds to this stress. Even before the coronavirus outbreak challenges healthcare providers like never before, physicians were experiencing a high rate of burnout. Several studies have pointed this out in recent years. A small but powerful indicative study published in the Indian Journal of Psychiatry in 2018 suggested that a significantly higher proportion of doctors in Indian setting experience stress, depression, and burnout. Out of the 445 responders in the study, 30.1% were found to have depression and 16.7% reported having suicidal thoughts. More than 90% of the participants reported some level of burnout.

The coronavirus outbreak has hugely magnified this problem, exacerbating the burnout rate in doctors and other healthcare staff particularly those involved in treating COVID 19 patients. Burnout is a condition where an individual experiences overwhelming mental and physical exhaustion owing to excessive stress. It not just affects the mental and physical health of the individual but also impacts his/her job related outcomes.

The COVID 19 burnout in doctors

In China, a cross-sectional study published in JAMA Network Open Journal in March 2020 found that the coronavirus outbreak had a devastating impact on the mental health of healthcare workers. Out of the 1257 respondents, 50.4% were found to have symptoms of depression, 34.0% reported insomnia, 44.6% reported symptoms of anxiety and 71.5% reported distress. The researchers concluded that working in the frontline was an independent risk factor for worse mental health outcomes.

Doctors at the frontlines of the pandemic are facing extremely challenging working conditions. Long grueling working hours, constant emergencies, witnessing a high death rate and a persistent struggle to save lives not just cause physical exhaustion but also result in an emotional and mental turmoil. In countries where severely ill patients exceeded the healthcare capacity to treat, doctors had to actually choose whom to treat and whom to let die. Absence of a clear treatment route is another major work challenge.

Wearing PPEs for long hours is itself a major challenge. Once your PPE is on your ability to eat, drink water or even go to the washroom is restricted. The grueling heat makes long hours of wearing PPEs worse. However, the most significant challenge is the threat from the disease itself. Being in the midst of patients every day puts doctors at a high risk of caching the infection themselves. By first week of May, over 500 doctors, nurses and paramedics had already been infected by Coronavirus in the country. An AIIMS doctors was applauded for putting himself at significant risk when he removed his goggled and face shield to be able to clearly see and re-intubate a seriously ill patient. This tells us how doctors are putting themselves at risk during this global pandemic. As doctors get infected and result in a further depletion of workforce, the remaining physicians face an even greater workload.

Apart from all the above concerns, one major concern for doctors and healthcare staff is the threat of carrying the infection to their home and families.

How to address the burnout crisis

As much as it is important to ensure the safety of doctors, it is equally important to help them address the mental and physical outcomes of burnout. Governments, healthcare providers and hospitals must initiate a series of measures to help address this burnout crisis.

Adequate availability of protective equipment

Strict adherence to properly wearing PPEs has been found to be effective in minimizing infection rate among doctor and healthcare workers. It is extremely important therefore that governments and hospitals ensure adequate supply and sufficient availability of PPEs for doctors. Adequate supply of PPEs and addressing the shortage concerns also allays the mental stress and fear among doctors. It is also important to ensure that doctors do not have to wear the same protective equipment for more than 8-10 hours.

Access to counseling and mental health experts

The World Health Organization has advised doctors to take extra care of their health by consuming healthy food, taking adequate rest and staying active. The body has also recommended de-stressing and avoiding smoking or drugs. Hospitals must ensure that doctors have regular access to counseling support to advocate healthy living. They must also have access to mental health experts to give them a proper outlet for their mental and emotional turmoil.

Offering alternative stay arrangements

Governments and private healthcare providers must also arrange for alternative accommodation for doctors and other healthcare staff members to allow them stay away from their families during the time they are treating COVID 19 patients. This takes off the extra pressure and concern about carrying the virus home.

Reduce burden by adding to the manpower

With the number of patients rising steeply every day, we need to find innovative ways to have sufficient backup resource of doctors. In this situation, it makes sense to train final year MBBS and PG medical students in critical care and keep them ready to be deployed in case the need arises.  

Continue Reading

Medically Speaking

RISING DELTA CASES AND EXPECTED HERD IMMUNITY: WHERE DO WE STAND?

Dr Rahul Pandit

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Even as India continues to fight against the deadly Covid-19 virus, SARS-CoV-2 variants are emerging, spreading and causing governments & public health experts to develop the best strategies to contain their spread constantly. There are currently 11 variants of the SARS-CoV-2 virus that the World Health Organization Trusted Source is monitoring. One of these variants, the Delta Plus variant — also known as B.1.617.2.1 or AY.1 —first detected in India, February 2021, has spread to many parts of the world. Towards the end of August, Maharashtra recorded 103 Delta Plus cases. Approximately 65% of the reported cases were amongst the unvaccinated population.  

So, how is this variant different, and can it escape vaccine protection? 

Delta Plus is a sub-lineage of the Delta variant first detected in India, acquiring the spike protein mutation K417N. In June, this variant was designated as a Variant of Concern (VoC) by the Indian government, citing its perceived increased transmissibility, ability to bind more strongly to receptors on lung cells, and potential to evade an antibody response.

Is the Delta plus variant more threatening?

The Delta variant has been held responsible for the second wave in India. Several other countries consider Delta as the factor behind a sudden surge of cases. It can be a trigger to the third wave. 

While India is battling against the Delta plus variant, few other parts of the world are bearing the brunt of C.1.2, a new SARS-CoV-2 variant. It was first reported in South Africa during May and eventually spread to China, England, the Democratic Republic of Congo, Mauritius, Portugal, and Switzerland. India has no cases of the new strain so far, and globally Delta variant is the more dominant one. However, what is of concern here is that the C.1.2 variant has a mutation rate of 41.8 mutations per year, i.e. twice the current global mutation rate of other strains, and it can evade the antibodies developed to ward off the Alpha or Beta variants. 

What impact does virus mutation have on the human body? 

The standard process of mutations impacts us when it leads to changes in transmission levels or on treatment. Mutations can have positive, negative, or neutral effects on human health. For example, negative impacts may include clustering of infections, increased transmissibility, ability to escape immunity and infect others who have poor immunity, neutralization escape from monoclonal antibodies, improved binding to lung cells and increased severity of infection.But positive impacts can make the virus becomes non-viable.

At this rate, how and when will we achieve herd immunity? 

A population is said to achieve herd immunity when large percentages of individuals become immune to a disease. Based on mathematical calculations, if vaccines could provide a lifelong, fail-safe shield against infection with SARS-CoV-2, it would need to reach 60-72% of people to establish herd immunity. But if vaccines are only 80% effective at preventing infection, 75-90% of people would need to be immunized — a high bar. 

If a third wave is triggered, a rise in infection rates may pose the toughest challenge yet for the government, owing to the weaker health infrastructure and staff availability. Robust serological surveys can show where the community is in terms of seropositivity, and in a way, low case numbers are an outcome of the spread slowing. However, in the journey towards herd immunity, many other factors determine daily case numbers and daily deaths, including the age and morbidity profile of those affected. 

Moreover, experts opine that herd immunity doesn’t confer immunity to the virus itself but only reduces the risk that vulnerable people will encounter the pathogen. 

However, most herd-immunity calculations don’t consider behavior changes, interventions, and rules. For instance, if people follow good physical distancing, the R0 (R0, pronounced “R nought,” is a mathematical term that indicates how contagious an infectious disease is) will go down, if they stop following the same after a while, the R0 will go up again. This will change the herd immunity threshold accordingly. 

Until large-scale vaccinations are made available, current forms of social distancing and use of face masks, along with all-inclusive case finding, testing, contact tracing, and isolation, need to continue. History tells us that we have never achieved herd immunity via natural infection concerning a novel virus, and SARS-CoV-2 is no different. Vaccination is therefore paramount. 

The writer is the Director-Critical Care, Fortis Hospitals Mumbai & Member-Maharashtra Covid-19 Taskforce

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