Unpredictable How Protective Vaccines Will Be Against New Covid Strains But Till Date Safe Against Outbreak: AIIMS Professor Neeraj Nischal

India’s Covid19 cases have exploded again, marking at record 1,03,558 on Monday. How do you define the surge again?

Neeraj Nischal: Honestly, this surge was expected as seen during the last major Influenza pandemic which happened a century ago. Globally, most countries have witnessed waves of surges, each bigger than the earlier one. There is a close relation between human behaviour and COVID19 cases. 

With number of cases settling early this year and pre-COVID activities resuming, people developed a false sense of security that the pandemic is over, and the virus is gone for good. Unfortunately, that is not so. People have become complacent and lowered their guard. This has led to this surge.

If we want to control the current surge and to prevent such future surges, we have to respect this virus by following COVID appropriate behavior and learn a way to survive and co-exist with it, else this virus will keep troubling us.

Recent reports indicate the severe mutations of the virus. Some also calling it ‘double mutant virus’. How consequential are such mutations now in terms of its fatality compared to the ‘first wave’ of Covid19? Many suspect that the virus has gotten smarter in the ways it launches an attack on our body. Your take?

Neeraj Nischal: Mutation is a natural process common to all organisms. Mutations lead to a change in the genetic structure of an organism that eventually expresses as a change in functional and/or structural characteristics. Those mutations which provides survival advantage are selected. RNA viruses like SARS-CoV2 virus are more prone to these mutations as their genetic replication lack proof reading, a tool essential to prevent errors in genetic replication. The more the virus replicates (as more and more people are getting infected), more are the chances of developing mutations. With respect to the virus, the net result is production of multiple mutant strains. However, it is only the fittest strain (high infectivity and low fatality) that eventually become the major strain in circulation, because virus being smart knows that if it kills its host (humans) then they also will not be able to survive. 

The more we expose ourselves to the virus, higher are the chances for this virus to evolve. In the process this may make immunity from previous infection and vaccines ineffective. However, it is still a matter of research whether these existing mutant strains of concerns can bypass the immune defence of all previously infected person or those who have taken vaccine. But this is what mutation is all about; fittest will survive and other will perish.

Do you see the new signs and symptoms of Covid19 in the second wave? In early phase of Covid19, some of the signs where were noted predominantly as breathing difficulty, cough, fever, pain and more impaired sense of smell.

Neeraj Nischal: Signs and symptoms of COVID19 have not changed. There are not many differences in the way patients are presenting with COVID during this surge. Irrespective of whatever the minor symptoms might be, life threatening complications are still related to the lungs. Moreover, during a rapid surge in cases, owing to the varied presentation of this disease, it wouldn't be incorrect to say that "any symptom could be a symptom of Covid-19".

A scan shows the damaged lung of a person hospitalized for COVID-19.Credit: Nathan Laine

The only change we have noted now is that people have become more fearless as far as this disease is concerned. Earlier there was rush to get tested at the slightest of symptoms or exposure which is not the case now. People are ignoring symptoms, not getting tested or isolating themselves leading to increase spread of infection. More and more people are opting for home isolation which has both positive (less burden on hospital) and negative aspects (patients are presenting late with advanced disease). 

It needs to be emphasized that the majority of cases are asymptomatic and an important cause of spread. Therefore, observing full precautions and practicing COVID appropriate behaviour is the key to prevent the spread of the pandemic.

Will the vaccines-- Covishield and Covaxin-- be equally effective against the new forms of virus of Covid19? Do you find any correlation as generally perceived that the current vaccine is tested against the old strain and may not be good against new variant strain?

Neeraj Nischal: Any vaccine that gets an approval undergoes rigorous scientific testing and validation. The primary aim of any vaccine is to reduce morbidity and mortality (its most important function) and reduce possibility of spread of infection by rapidly clearing out virus in those who get infected. 

One has to remember difference between getting infected (mere presence of pathogen)and getting diseased (development of symptoms and complications). After getting vaccinated, one can still get infected, but vaccine’s role is to ensure that the person does not develop severe disease. This means no ventilator requirements and less chances of death. If someone gets infected after vaccination, it doesn’t mean it is because of mutant strain. It is obviously difficult to predict how protective these vaccines will be against the newer strains but till date it does not seem to be a concern as far as the Indian outbreak is concerned.

However, since the virus is continuously evolving, we need to keep assessing the overall efficacy of these vaccines over time. There is a chance that the vaccines may be less efficacious against the newer strains, it is hard to say at present. But the probability of it failing completely, is less. 

Over time, as we see new strains, the vaccine may also evolve. It may become like the Influenza vaccine where we might need a shot yearly based on the prevalent strain. However, as of today, the best bet is the current vaccine.

Whatever be the case, one thing is very clear that COVID appropriate behaviour is definitely going to work against any mutant strain. 

A cell (blue; artificially coloured) is flecked with SARS-CoV-2 particles (yellow).Credit: Dr Steve Patterson/Science Photo Library 

Therefore, it is important that social vaccination (masking, physical distancing, hand hygiene and isolating when having symptoms) and biological vaccination will have to go hand in hand till this pandemic lasts.

You have been part of the team at AIIMS managing such cases. No doubt, the facility as well the manpower were stretched beyond capacity in such testing times. Now again with rising cases of COVID-19 virus, what do you suggest? What measures would you advice to the hospitals and people?

Neeraj Nischal: The suggestion to the people has and always will be the same. COVID appropriate behaviour with masks, hand hygiene, and physical distancing. Along with this, all those eligible, should be vaccinated. Fear the virus not the vaccine. Public doing their part collectively helps more than the contingencies that hospitals can take. After all, beds and resources are a physically limiting factor in every hospital that cannot change rapidly in the short term.

Hospitals should do their part in this scenario by appropriate resource allocation. Ensuring duty hours to prevent staff burnout would become important. However, the goal is to flatten the curve, and this rests on the shoulders of the people, not the hospitals. 

There is lot of information, rather misinformation on COVID19 on internet and social media platforms. 

All research articles that get published do not always find place in daily clinical practice. So, don’t try to self-medicate by reading such articles. Always seek medical advice.

As an expert in field of medicine, what is your advice to public for boosting immunity that can help them fight this deadly virus? 

Neeraj Nischal: Vitamin supplements and diets have become a fad in today's world. These stem from the root cause of an unhealthy lifestyle. The science of medicine is not all-knowing. 

Yoga and breathing exercises have shown soft benefits in multiple respiratory diseases. It is a part of a healthy lifestyle and is definitely beneficial. 

Rather than the benefits of medical supplements, people should focus on a healthy lifestyle. 

Immunity is best boosted naturally, with good nutritious home food, and regular exercise ensuring a non-sedentary lifestyle.

Particles (yellow; artificially coloured) of SARS-CoV-2 infect a human cell.Credit: NIAID/National Institutes of Health/Science Photo Library