Coronavirus disease, also known as COVID-19 is an infectious disease caused by the newly discovered strain of Coronavirus (SARS-COV-2) which has resulted in a global pandemic.
The disease whose first case was recorded in December of 2019 in Wuhan province in China was declared a global pandemic by WHO on 11 March 2020 and is currently estimated to have resulted in more than a million deaths worldwide whereas more than 60 million people have tested positive for the virus.
Hello Dr. Sony and thank you for speaking to us today, could you introduce Covid-19 to us before we delve into our today’s topic?
Thank you for having me here. As everyone must have known by now COVID-19 is an infectious disease caused by the SARS-COV-2 strain of Coronavirus. COVID-19 is an abbreviation for Coronavirus Disease and 19 denotes the year of the first case (2019).
How does the virus spread from one person to another?
The virus usually spreads when people infected with the virus cough or sneeze, releasing droplets containing the virus spreading it to another person.
It can also spread through contaminated surfaces and direct contact with the person affected by COVID-19.
What are the symptoms of people suffering from COVID-19?
The person suffering from COVID-19 can present with a variety of symptoms depending upon the severity of the disease. The most common clinical features being fever, dry cough, and fatigue.
People may experience sore throat, loss of sensation of taste and smell, generalized body aches, headache, confusion, nausea, vomiting, and diarrhea.
In a few cases, people with the disease may be asymptomatic and show none of the above symptoms.
I see, are there any long term complications of COVID-19 too?
People may experience temporary stress-induced hair losses, however, there is no direct evidence that COVID-19 causes hair loss itself. Symptoms like brain fog and tooth loss in patients have also been reported but a direct association with COVID-19 is yet to be established.
Well in that case. Do these people who are infected, but showing no symptoms, do they transmit the disease to a healthy person?
Yes, people showing no symptoms can also spread the infection to a healthy person.
Should every person developing symptoms seek specific medical attention?
No, most of the people infected with COVID-19 experience only mild to moderate respiratory illness and do not require any special treatment or hospital stay.
In that case, what kind of cases should seek immediate medical care?
People experiencing fever and/or cough associated with difficulty breathing or shortness of breath, people with persistent chest pain, and people with high fever(>38°C/100.4°F) should seek immediate medical attention.
Is there any vulnerable group?
How can we protect ourselves from the disease?
This is a very important question. Simple precautions taken can go a long way in protecting ourselves and others from the disease.
Preventive measures include social distancing, wearing masks properly, avoiding crowds and direct contact with people, and coughing onto a bent elbow.
While wearing masks it is preferable to use masks without exhalation valves as this type of mask doesn’t prevent the spread of infection to others.
In addition to masks, face shields and goggles can be used to protect eyes. Along with all these regular hand washing with soap also helps in protection from the disease.
As the disease has symptoms similar to other simple respiratory illnesses, how does one get diagnosed with COVID-19?
Infection with SARS-COV-2 is detected using a molecular test known as Polymerase Chain Reaction (PCR). In this test people with symptoms similar to COVID-19 get samples collected from the nose and/or throat with a swab. It detects the presence of an active infection.
I see. What do you do when you get diagnosed with COVID-19?
The person diagnosed with COVID-19 usually stays in isolation, separated from other people, typically in a medical facility as receiving medical care is easy. But as I already said for people who are not at risk of developing the severe disease can isolate at their home for at least 10 days and additional 3 days without symptoms after testing positive and repeat PCR.
Sometimes people are confused between isolation and quarantine could you shed some light on how quarantine is different from isolation?
A good question. Quarantine is for any person who has come in contact with a person who has tested positive for COVID-19 with or without symptoms. The person has to stay at home or a designated place as he/she might have been infected.
Okay. What is the cause of death in people with COVID?
The most common cause of death in people with Coronavirus disease is Viral pneumonia leading to Acute Respiratory Distress Syndrome (ARDS) and Respiratory failure.
Most patients with severe COVID-19 require prolonged ventilator support, making cases of death due to Ventilator-associated pneumonia common.
How do you treat COVID-19? Do antibiotics work against it?
COVID is a virus borne disease, so antibiotics don’t work against it. Antibiotics work only against bacterial borne diseases. However, it can be given to patients with COVID-19 to prevent or treat a secondary bacterial infection.
If so are there any treatment modalities for COVID 19?
Currently, the patients are being treated symptomatically and given supportive care with Oxygen and Ventilators in severe cases. Scientists all over the world are trying to develop a treatment for the disease. Many potential vaccines are also being studied and are under clinical trials.
Moving on. The term vaccine seems to be a hot topic in light of vaccines being prepared for COVID-19. What is a vaccine? Will they be safe to use?
Vaccines are biological products containing an agent that resembles disease-causing micro-organism and is often made from weakened/killed form of the microbe which stimulates the person’s immune system to provide immunity to specific diseases. The microbe is weakened and killed so that it doesn’t cause much harm but is potent enough to trigger the immune system to provide immunity against the disease. Vaccines are generally safe to use as they undergo various levels of rigorous trials (Animal trial followed by three stages of human trials) to check for common side effects and any safety concerns in regards to the vaccine.
As the vaccine is still under clinical trials and may take some time to be available for the general public, many have put forward the opinion of herd immunity as a strategy against coronavirus disease. What are your thoughts on this?
This is a very good question. Before answering the question I would like to explain what herd immunity is exactly. When most of the population is immune to an infectious disease, this provides indirect protection to the remaining people of the community/population/herd who are not immune to the disease.
This can be achieved either through natural infection or through a vaccine. Since a vaccine for coronavirus hasn’t been made available yet, the only way we can get herd immunity as of now is through natural infection. But for herd immunity to occur most of the people in the population need to have developed immunity following a natural infection. I think attempts at reaching herd immunity by exposing a large group of people to the virus seems unethical and counterintuitive as indiscriminate exposure of people of all age groups and health status will lead to unnecessary infections in vulnerable groups.
There are still many things regarding immunity to coronavirus that we have very little idea about, we don’t know for sure how strong and long-lasting the immunity is, once the patient recovers from coronavirus and also the percentage of the population who are immune.
For herd immunity to occur large group of the population should be immune for a long period, even then the percentage of people developing antibodies to develop herd immunity varies according to disease which makes it difficult for a disease that is still under study.
Wow, I didn’t know that! So you think waiting for vaccines is the best option?
Absolutely, it prevents unnecessary exposure of people and helps save lives. Till the vaccines arrive, we need to take care of ourselves and the people around us by taking proper precautions as I mentioned earlier in the interview
I see. What are the vaccines which are currently under clinical trial?
There are currently about 151 vaccines in Pre-clinical/Animal trials, 17 under phases I, 13 under phase II, and 10 vaccines under Phase III of clinical trials.
Why are there so many vaccines? Wouldn’t they be better off developing a single vaccine properly?
Well, this gives researchers multiple options in case the leading vaccine fails to deliver on its promise.
Can you tell us about a few vaccines, which are showing promise?
Final analysis of Pfizer vaccine Phase III trial was recently done, which showed it to be 95% effective in preventing the disease, also vaccines like Moderna and AstraZeneca are in Phase III of clinical trials.
Are these vaccines, the ones you mentioned all the same, or do they have different components?
Well, Pfizer and Moderna are mRNA-based vaccines, where fragments of mRNA code for part of the virus, which when injected in the body, copies of the parts are made which triggers an immune reaction in the body. Whereas the AstraZeneca vaccine uses a weakened viral particle capable of eliciting strong immune reactions.
Okay, can you tell me about the pros and cons of these vaccines?
Sure, The RNA-based vaccines Pfizer and Moderna can be developed relatively quickly as they require genetic sequencing only, being easy to manufacture, production can be done relatively cheap and these fragments do not cause COVID-19.
However, these vaccines are new vaccines, new in the sense that there are no approved RNA vaccines for medical use in humans so they will probably have to undergo considerable regulatory hurdles before being available for use. Also as only a fragment of the virus is made, the immune response produced may be weak, thus necessitating multiple booster doses.
AstraZeneca vaccine which uses a weakened viral vector for triggering immune response has its own merits in delivery of highly specific antigens to target cells and high expression of antigens after vaccination, thus only a single dose can provide long-term protection.
Did these vaccines during trials show any side effects?
Trials of the Moderna vaccine have shown that participants developed fatigue, muscle pain, joint ache, and headache as severe symptoms whereas for the Pfizer vaccine severe side effects included fatigue and headache. Fewer than 2% of people involved in trials for the Moderna and Pfizer vaccine developed severe fever (>39C).
Longer-term side effects of these mRNA vaccines include the possibility of flaring up of lupus in people suffering from it.
2 in 3 people undergoing trial for the AstraZeneca vaccine developed transverse myelitis, the development of which halted the testing of the vaccine. They later published a report saying there was insufficient evidence to link these illnesses were related to the vaccine, the company has since resumed phase III trials in the UK, Brazil, South Africa, and India. Trials are yet to resume in the US.
As you mentioned above about possible flaring up of lupus as a long term complication of mRNA vaccine. What is lupus and why does it flare up on vaccination with the mRNA vaccines?
Lupus is a multi-systemic autoimmune disease that occurs when your body’s immune system attacks your own tissues and organs. It is not a certainty that these vaccines cause flaring up of lupus, it is just an implied possibility, as these vaccines enhance the immune system and these antibodies may act against the person’s genetic code resulting in flaring up of this autoimmune disease.
It is just a possibility that is undergoing trials and there is no evidence as of now that these vaccines cause or make autoimmune diseases worse.
Okay moving on. How many doses of the vaccine are required?
Both Pfizer and Moderna vaccines require two doses separated by several weeks (3 weeks apart in case of Pfizer and four weeks apart in vaccination with Moderna vaccine).
Once the vaccines have developed, do people who were previously infected with COVID require vaccination?
I would say they would require vaccinations. As I already mentioned there is a lot to know about immunity regarding COVID-19. But there are several vaccines already which are more protective than natural infections, for example, people receiving zoster vaccines are 20 times less likely to develop shingles in adulthood compared to people who catch chickenpox (natural infection). Various researches have shown waning antibody titers over 2-3 months which suggests that re-infection with COVID-19 is very much a possibility.
Early results from animal trials have shown vaccines to produce a greater antibody level compared to that from natural infection.
What do you think, considering the side effects is it worth it to take the vaccine?
Clinical trials of these vaccines did not reveal any serious problems. The side effects are unpleasant rather than dangerous. I think it is a small price to pay for getting immunity from COVID-19 when considering what it can do.
Okay. How effective are the vaccines?
The final analysis of the Phase III trial of Pfizer vaccine showed it to be 95% effective in preventing infections, the efficacy was found to be consistent across different age groups, races, and ethnicities.
Whereas early reports from Phase III clinical trials of Moderna vaccine, shows it to be 94.5% effective in preventing Coronavirus disease.
Recent results regarding the AstraZeneca vaccine claim it to be 70% effective on average reaching up to 90% efficacy based on dosing, not quite at par with Pfizer and Moderna vaccines but higher than the 50% threshold deemed acceptable by the WHO and the FDA.
I see. Can you tell me about the availability of the vaccines?
Though no specific date has been given, based on current projections Pfizer expects to produce 50 million vaccine doses in 2020 and up to 1.3 billion by 2021. As the vaccine requires two doses 3 weeks apart, the vaccine rolling out in 2020 will be good for only 25 million people, 2021 is when people who are not considered high risks will be getting the vaccines.
Where will the vaccines go first and will it be able to meet the demand of infected people worldwide?
It is expected that despite significant efforts to ramp up the production of the vaccine, the global demand for vaccines is expected to far exceed the supply. Moderna has reached an agreement to supply over 100 million doses to the US and about 80 million to The European Union among others, whereas about 200 million doses of the Pfizer vaccines has been booked by The European Union, about 80 million by Japan, and 50 million by the United States among others
Ok in that case. How much will these vaccines cost?
Pfizer vaccine is expected to cost around 19.5 US$ for a single dose whereas the Moderna vaccine will cost you about 32-37 US$ per dose. AstraZeneca vaccine is estimated to come at around 3-4 US$ per dose.
Is there any advantage of Moderna over Pfizer or vice versa?
Despite having similar efficacy and safety profiles the practical advantage that Moderna holds over Pfizer is that its temperature requirement for safe distribution of vaccine is much simpler. Moderna requires 4°C of temperature, which is found in the household fridge for distribution whereas Pfizer needs -70°C, which may be found only in major hospitals. For storage beyond a month, Moderna requires -20C, which is still easier to secure as compared to Pfizer’s -70°C.
Another advantage of Moderna over Pfizer is that it can be stored in the fridge for 30 days whereas Pfizer can last for a maximum of 5 days.
Why are some people reluctant to get vaccines once they are available?
Globally, the fear of side effects followed by concerns about the clinical trials moving too fast seems to be the major cause of reluctance among people to take COVID-19 vaccines.
In that case. What do you think should be done to generate higher acceptance for the vaccine?
I think transparency is key here, people should be made aware of the side effects related to vaccines. People administrating vaccines should make people aware that these adverse reactions can feel severe but are temporary, the companies need to warn people so that they do not feel they are being kept in the dark, public health professionals come up with ways to convince people the use of vaccines far outweighs the possible side effects.
The companies need to assure people that the side effects of these vaccines are seen mostly after the second dose means the vaccine is working well and the body had a good immune response to the first dose.
Any final words before we wrap up the interview?
We are amidst a global pandemic and it will take time even after the vaccines have been distributed for the disease to completely go away, so continuous cooperation and coordination is required between different authorities. Currently preventing the spread of the disease by following local policies of the country, proper usage of masks and handwashing, and waiting for the vaccine is the best bet in the effective management of COVID-19. To simply put 3 C’s should be avoided to stay safe from the virus. Avoid the following:
- Crowded places
- Close-contact setting
- Confined spaces
Thank you for taking the time to speak to us. I learned a lot of new things today about Coronavirus disease, herd immunity vaccines. Thank you, doctor.
And until our next Q&A session please share us and like us so that we may continue to provide you with the latest in medicine, health, and fitness free of charge. You may also join the Gilmore Health newsletter to receive the latest in health news. If you are interested in any subject that you wish us to cover please share it with us in the comments area below!
Gilmore Health Q&A Sessions: