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| COVID-19 vaccination at Joint Base Pearl Harbor - Hickam 29th Dec 2020. USN Photo. |
Less than a year ago, during the early days of the pandemic, we witnessed COVID-19 outbreaks onboard naval vessels such as the aircraft carrier USS Theodore Roosevelt and the Taiwanese supply ship ROCN Panshih. Thankfully, military leaders around the world have learnt from these incidences and have since implemented the necessary measures such as pre-deployment quarantine, mask-wearing and safe-distancing to drastically reduce the likelihood of such large scale outbreaks among service personnel. Though effective, these disease preventing measures are highly disruptive and restrictive and have a negative impact on moral, work efficiency and productivity.
Now, slightly more than a year since the first cases were reported in the Chinese city of Wuhan, a new tool is made available to fight the novel coronavirus SARS-CoV-2. I am referring to the COVID-19 vaccines that are now starting to be administered to the masses in many countries. It will be through the widespread inoculation of vaccines that will give the world a fighting chance of ending the pandemic so that life can eventually return to normal, well at least a post-pandemic normal.
In many democratic societies, COVID-19 vaccinations are given on a voluntary basis and the current challenge is that many people are unsure if they should receive the vaccines. There are even some who would refuse to believe in the science of disease prevention and would reject the vaccines outright. Herd immunity and therefore the protection of the larger population cannot be achieved if not enough people take up the vaccine.
During this initial vaccine roll-out phase where availability is low, governments are trying their best to prioritize vaccinations for frontline medical personnel and essential services personnel, apart from those who are most vulnerable, like the frail and elderly nursing home residents. For military personnel, if your commander " volunteered " you for the vaccine, or if vaccination is listed as an operational requirement, it might be difficult or even impossible to refuse.
So, are the COVID-19 vaccines safe? The short answer is YES. And I will attempt to explain the science of vaccination in simple terms from the perspective of one who has already received the first dose of the COVID-19 vaccine.
Disclaimer : I do not work for any governmental organizations or NGO. I do not own shares or have any direct interest in any pharmaceutical companies, including those that research or produce vaccines.
How Vaccines Work
Vaccines protect us from infectious diseases by training our immune system to recognize and eliminate those external threats to our bodies with much greater efficiency than it would if left to its own devices. When our immune system first encounters a pathogen such as a bacteria or a virus, it takes time to establish it as foreign to the body. It also takes time to organize an appropriate response to neutralize the threat, usually through some kind of antibody or cellular action.
The process of vaccination presents the immune system with the necessary information to prime it to react almost instantly should it encounter the real threat at a subsequent time. It is like a full-dress rehearsal, or a military exercise to prepare the soldiers for no-duff encounters. Once the immune system had familiarized itself with the infectious agent, it forms memory cells, B-lymphocytes that basically archives whatever the immune system has learnt. Any future encounter with the actual pathogen will result in an immediate activation of immune responses including rapid ramping up of antibody production and cellular defenses, usually with lethal consequences to the invading microbe. And hopefully this instant immune response will spare the host ( that's us ) from contracting the disease or at least avoid severe symptoms.
Preventive Medicine
Ever since the English physician and scientist Edward Jenner created the first modern vaccine against smallpox in 1796, our knowledge in immunology and expertise in vaccine development has increased exponentially. There exist today many safe and effective vaccines against a variety of infectious diseases including influenza, measles, yellow fever, hepatitis B, dengue and human papilloma virus, just to name a few.
Collectively, vaccines have helped save literally hundreds of millions of human lives in the past centuries. Smallpox killed an estimated 300 million people in the 20th century alone before it was finally declared eradicated in 1980.
In addition to the of loss of lives, many of these infectious diseases cause severe morbidity and long term sequelae which can include blindness ( smallpox ), flaccid paralysis ( poliomyelitis ), permanent mental retardation and recurrent seizures ( Japanese encephalitis ) that can threaten the livelihood of any survivors and their care givers.
Where as most treatment methods in modern western medicine are curative and does nothing to help people avoid getting sick, the process of vaccination is one of a handful that is truely preventive in nature and is considered the most cost effective way to ward off infectious diseases.
Historical Vaccine Development
Developing a new vaccine against any infectious agent is no mean feat. It takes years, sometimes even a decade or two, to research, design, produce, trial, obtain regulatory approval and finally market a vaccine. Even then the job is never finished as post-market surveillance for adverse reactions continues for many, many more years. It requires the combined effort of a multi-disciplinary team of researchers from immunologists, pharmacists, micro-biologists, geneticists, bio-engineers, epidemiologists, statisticians to clinicians. Success is never guaranteed.
The costs involved can be staggering too. The International Monetary fund ( IMF ) estimated R&D costs of between USD200 to USD500 millon for each vaccine and an investment of another USD500 to USD1500 million for facilities to produce the vaccine in scale.
So how could COVID-19 vaccines be possibly developed, approved and mass produced within less than a year? Can they still be safe?
Developing A Safe Pandemic Vaccine
The COVID-19 pandemic represented an unprecedented global threat to humankind through its medical, socio-economic and environmental impacts. As of today, 104 million have contracted the disease of which 2.27 million had died. Entire cities, even whole countries are in protracted and sometimes recurrent lock-downs in mostly futile attempts to control the epidemic. Jobs and livelihoods are lost as trade and movement of people and goods are severely disrupted. Desperate times calls for desperate measures and fortunately advances in science and technology have made it possible for the accelerated but safe development of the pandemic vaccines. These are some of the enabling factors :
Genomics - advances in the field of genomics have allowed scientists to map out entire genomes of organisms through rapid DNA-sequencing. The structure and function of the genome can then be analysed and determined. Back in 2003 when the human genome was first sequenced, it had cost a billion dollars and had taken 13 long years to complete. Today, the vast increase in computing power, among other things, has allowed the human genome to be sequenced in just 2 days, for about $1000. The COVID-19 epidemic started in Wuhan in early December 2019. By 10th Jan 2020 the entire genome of the SARS-CoV-2 was sequenced, uploaded and freely available to the global scientific community of researchers.
Co-operation - Countries, governments, institutions, corporations and the academia are joining hands in ways never imagined before to combat the global scourge of COVID-19. Through efforts such as GISAID ( Global Initiative on Sharing All Influenza Data ) scientific information on the influenza and the corona viruses are shared on a global scale. Universities are partnering big pharma to research on vaccines like the Oxford-Astra Zeneca duo and the Duke-NUS-Arcturus pairing. Vaccine candidates may also have their clinical trails done concurrently in several countries where the disease burden are the highest and that necessitates the highest level of co-ordination among governments and researchers.
Funding - In the past, vaccine research is mainly funded by individual pharmaceutical companies. Now, governments are pouring hundreds of millions of dollars to drastically accelerate vaccine research and development, usually in exchange for the priority to procure the vaccines when eventually available at an agreed special low price. While money may not be the solution to every problem encountered, the timely accessibility of funds can certainly pave the way for smooth processes.
Accelerated Clinical Trials - Regulatory authorities such as the FDA ( Food and Drug Administration ) have drastically shortened the time required to complete each phase of the clinical trial, without compromising on safety, partly by monitoring the vaccine trials on the fly. Where as in the past data for each phase was submitted for approval only at the end of the phase, now data is continuously uploaded for the authorities to review in real time, so that approval can be granted immediately for progression to the next phase, provided there are no safety issues involved. Another trick is to combine clinical trial phases. Some trials combine phase I and II while other might combine phase II and III. Also during a pandemic where there are high incidences of infection, the time required to reach a clinical end point ( for example, after X number of people involved in the trial got infected ) can be achieved much faster than during normal times when the disease burden is low, and the phase can be concluded earlier.
New Vaccine Technology - messenger RNA ( mRNA ) vaccines represent a new way of manufacturing vaccines and have never been utilized on other vaccines approved before the pandemic. Compared to the traditional way of vaccine manufacturing, these new vaccines have the advantage of using non-infective elements, have much shorter manufacturing time, have the potential to be engineered to target several diseases at the same time and can be developed in a laboratory using DNA templates and readily available materials. All these means that mRNA vaccine production can be more easily standardized and scaled up without affecting the yield, allowing for cheaper and faster roll-out. The Pfizer-BioNTech and Moderna vaccines are examples of mRNA vaccines and are both among the first to complete large scale clinical trials with flying colours. Here's the link to learn the difference between RNA vaccines and conventional vaccines.
Capacity Building - Pharmaceutical companies are preparing and expanding their manufacturing facilities for large scale vaccine production as the vaccines are concurrently being developed so that production can be ramp up rapidly once approval is given. The logistic and transportation industries are similarly preparing for vaccine distribution with expansion to cold storage facilities and delivery fleets. Production of ancillaries required for vaccine production, delivery and administration such as special low temperature glass vials, dry ice and special low dead-space syringes are also increased in anticipation of a huge surge in demand.
All these measures, coordinated on a global scale, have made it possible to produce safe and effective vaccines within a record breaking period of less than a year. With this in mind, let's take a closer look at the Pfizer-BioNTech vaccine, the world's first successful mRNA vaccine, now being administered in the US, UK, Israel, Singapore and several countries that acted early enough to procure it in sufficient quantities.
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| In Pfizer We Trust Photo : Wikipedia |
Pfizer-BioNTech COVID-19 Vaccine
The American pharmaceutical giant Pfizer's collaboration with BioNTech AG, a German biotechnology company specializing in precise immunotherapies for the treatment of cancers and infectious diseases, started in Aug 2018 with the original aim of producing mRNA-based influenza vaccines. When the COVID-19 outbreak started in Dec 2019, the focus turned towards the development of a coronavirus vaccine.
Pfizer's development of a novel vaccine against COVID-19 was initiated on 10th Jan 2020, the very day the genetic sequences of the SARS-CoV-2 virus was released by the Chinese Center For Disease Control and Prevention via GISAID. It would ultilize BioNTech's already mature mRNA technology. Several variants were created, four of which entered early clinical trials ( combined Phase I/II ) which began in April and May. It would eventually emerge that the most promising vaccine candidate with the best safety profile was the one with the code name BNT162b2. Phase III trials for BNT162b2 started in July involving 43538 participants from the US, Germany, Brazil and Argentina with diverse racial and ethnic backgrounds. By early November, preliminary data suggested the vaccine to be over 90% effective with no serious side-effects. The final results indicated an efficacy of 95% in preventing serious COVID-19 disease, paving way for the declaration of Emergency Use Authorization ( EUA ) by the UK on 2nd Dec and by the FDA on 11th Dec 2020.
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| mRNA vaccine at the cellular level. Illustration : New England Journal of Medicine |
BNT162b2 is a lipid nanoparticle-formulated, nucleoside-modified mRNA encoding the full-length spike of the SARS-Cov-2 virus. Modifying a key nucleoside of the mRNA strand was crucial in reducing the unpleasant side effects of the vaccine while the lipid encapsulation protects the extremely fragile mRNA and facilitates its entry into the cells of the vaccine recipient. The mRNA would then instruct the cell to produce many copies of the spike-protein which would then trigger an immune response, leading to the eventual production of protective antibodies against the virus. The spike-protein is just an antigenic part of the coronavirus and is safe and non-infectious. The mRNA do not enter the nucleus of the cell where all the genes are located and therefore could never ever come into contact with or modify your DNA. They would be completely degraded and destroyed by all sorts of enzymes in the cells within probably less than 48 hours of vaccination.
The BNT162b2 COVID-19 vaccine is marketed under the brand name Comirnaty, with an international non-proprietary name ( INN ) of Tozinameran. It is supplied in vials of 5 doses and must be stored in ultra-cold temperatures between -60C to -80C, making its distribution and storage a logistical nightmare. It is transported with dry ice in special cold boxes with thermal sensors and GPS trackers to ensure compliance with the manufacturer's recommendations. It must be thawed before use. Its shelf-life is only 5 days when stored at the normal fridge temperatures between 2C to 8C and must be used within 6 hours of reconstitution with saline.
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| Receiving the first shipment of COVID-19 vaccine at Naval Hospital Camp Pendleton 15th Dec 2020. Note ski gloves and thermal sensor. Photo : USN |
The vaccination schedule requires 2 injections of 0.3ml 3 weeks apart. Effective protection against COVID-19 disease is observed just 10 days after the first shot, with the second shot acting as a booster dose to further enhance the level of protection. Possible side effects, mostly mild and transient, include the usual array of pain or swelling at the injection site, fatigue, headache, nausea, giddiness, post-vaccination fever, allergic reactions with rashes and rarely anaphylaxis, a potentially life threatening form of drug allergy, with an incidence of 11.1 per million.
Anyone can receive the Pfizer-BioNTech vaccine apart from those with a past history of anaphylaxis, those who are severely immuno-deficient, pregnant women and young people below the age of sixteen years old. The latter two groups because they were not included in the vaccine's clinical trials so no data on the safety of the vaccine exist at the moment for them. Clinicians do not yet know the protective duration of the vaccine as it is so new but it is hoped that the protection can at least last for 2 to 3 years, if not longer. Otherwise, the vaccination will have to repeated at regular intervals. Another unknown at this stage are the long term side-effects of the vaccine, if any. But from the basic science of immunology governing the design and production of vaccines and our collective experience dealing with many other vaccines, I believe the risks of long term side effects are not high. Vaccine side effects are usually observed within days or at most, within weeks after inoculation, not after months or years!
Pfizer manufactures the BNT162b2 vaccine in Michigan and Belgium. It has plans to deliver 50 million doses of the vaccine by end of 2020 and 1.3 billion doses in 2021. How much does it cost? BioNTech's chief strategy officer Ryan Richardson had said that the vaccine would be priced " well below typical market rates ". The vaccine would also have differential pricing depending on where and to which region it is being sold. It is common knowledge that the US government paid Pfizer $1.95 billion for an initial 100 million doses of the vaccine. So that works out to $19.50 per shot or $39 to vaccinate each person.
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| Hospital corpsman prepares Moderna vaccine at US Naval Hospital Okinawa, 29th Dec 2020. Photo : USN |
Adverse Reactions? What Adverse Reactions?
I was given my first shot of the Pfizer-BioNTech vaccine on 19th Jan 2021. Before the vaccine was given, a series of questions were asked to ensure the vaccine recipient was not feeling unwell, was not on anti-coagulants, did not have a past history of severe drug allergy, did not receive any other vaccines within the past 14 days, were not to be pregnant or breast feeding and other nitty gritty stuff.
The vaccination process was mostly painless as a fine gauge needle ( 25G ) was used and the injection volume was small ( 0.3ml ). It was an intramuscular injection into the deltoid muscle ( upper arm ) and was completed within a couple of minutes. I had then to wait for 30 minutes at a holding area to be monitored for any possible adverse reactions before being allowed to leave for home. I was issued with a certificate of vaccination with the date for the second shot exactly 3 weeks later.
The only minor side effect that I encountered was a slight soreness at the site of injection which had began 12 hours post-vaccination. Even at its peak intensity at 24 hours, it was at best a mild tenderness which did not affect any of my routine activities. The ache was largely resolved by 36 hours post-vaccination. The injection site was never swollen or red at anytime and I did not develop any fever.
My stamina was not affected by the vaccine as I had attained the same timing for all four of my 10 km runs, the first of which was done 2 hours prior to vaccination and the rest on each of the 3 consecutive days immediately following the vaccination. I even managed to obtain the fastest ever timing for my usual 29 km weekend long run on day 10 post-vaccination.
In case anyone wonders why I seem to be training a little more than the average person, exactly a year ago, I had failed in my first 100 mile ultra-marathon attempt, just before COVID-19 closed many borders to travelers. Another 100 km ultratrail event which I had enrolled in for the month of May was cancelled. I intend to return to complete these unfinished events sometime in the near future. So COVID-19 or not, I continue to motivate myself to train hard, and hope for borders to reopen soon.
Admittedly, not all vaccinations are smooth going. Perhaps I am just lucky. A friend of mine who is a major in an elite commando unit who had also received the Pfizer vaccine a few days after me had complaint of pain in his arm which lasted for several days. There are a few others whom I have known that had to take a couple of days off from work because they felt feverish or fatigued, but none are really serious events. I have since learnt that the second dose of the vaccine might possibly illicit a slightly stronger reaction from the body and I will update this article accordingly.
* 9th Feb Just completed second and final dose of the Pfizer vaccine. The soreness at the site of injection seemed to begin slightly earlier at 5 hours after vaccination but its nothing more than a niggling ache.
* 14th Feb The soreness, though slight, persisted for a total of more than 4 days. There was a slight swelling at the injection site which lasted for about 3 days. Completed a 78km overnight long run on day 4 post-vaccination with no problems except for some blisters.
So it seems true that once primed by the first dose, the body's reaction to the subsequent dose is slightly more intense, but still well manageable.
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| #SINKCOVID : One of the vaccine awareness campaign poster, US Navy. |
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| Commemorative sticker, Washington DC Veteran Affairs Medical Center. 15th Dec 2020 Photo : USN |
Why Should Anyone Be Vaccinated
The most obvious answer to this question is that COVID-19 infection is a potentially serious disease that can kill, regardless of age. The younger population with a more robust immune system generally fair better but are certainly not completely spared the debilitating symptoms, long term sequelae and even the possibility of death with COVID-19 infections. The SARS-Cov-2 case fatality rate can range from a relative low of 0.2% in the 20 to 29 years old group, to more than 20% for those above 80 years old.
Even if a person survives the acute infection, there are still the protracted post-infection sequelae or what is commonly known as " long COVID " to worry about. Chronic fatigue syndrome, asthenia, coronary syndromes, pulmonary embolism and stroke have all been reported with increased incidences among convalescent COVID patients.
One of the major reasons for vaccine hesitancy is the concern over the safety of these new and untried vaccines which are pushed out in record time. This worry is then exacerbated by inaccurate and frequently false information circulating on the internet and social media. In some communities, COVID vaccines are said to cause infertility. In others, they are the conspiracy theories that governments are trying to implant microchips into our bodies through the process of vaccination to ultimately control us. Some reports would highlight deaths occurring within days of vaccination, but none would eventually be proven to be caused by the vaccines directly. The Russians even claimed that mRNA vaccines will alter our genes and turn us into chimpanzees, absolutely impossible and laughable to a trained scientist, but would seem very real and plausible to the lay person not so well versed in science. Then there are people who had never taken the vaccine but would talk about the side effects and adverse reactions as if they were the experts, except they weren't!
Another important but often overlooked and understated reason to get vaccinated against COVID-19 is the fact that there is still NO CURE for the disease. All those antiviral agents like Remdesivir, Lopinavir, anti-parasitic agents like Ivermectin and anti-inflammatory agents like Dexamethasone and Hydroxy-Chloroquine do not eradicate or even completely inhibit the coronavirus. They are merely useful at different stages of the infection to slightly reduce the morbidity and mortality rates among a carefully selected cohort of COVID-19 patients. All the hospital and intensive care treatments, ventilators, extra-corporeal membrane oxygenation ( ECMO ) machines, are by nature supportive only to help the severely ill patients through a very serious and stressful period and provide them with whatever their bodies would require to recover from the infection. Sadly, there are many who do not make it despite having the best care money can possibly buy.
And then we will have to ask ourselves how we can protect those in our communities who in one way or other missed out on the vaccine. The most obvious groups would be the children and teenagers under the age of 16 years old, those who are pregnant and those with a past history of severe life threatening drug allergies. They are excluded in this initial round of vaccination. But what about those who had received the vaccine but subsequently failed to develop a lasting immunity against the coronavirus? The fact that the Pfizer vaccine is 95% effective and that the Moderna vaccine is 94.1% effective against the development of symptomatic COVID-19 disease means that of every 100 persons vaccinated, roughly 5 would fail to acquire the intended protection. The figure is worst for the above 65 years old population as the Pfizer vaccine was found to be only 85% effective among the elderly. How then to protect the 15 out of every 100 elderly people whom though vaccinated still effectively missed out on the protection? If only every single vaccine eligible persons within the community could step out and receive the vaccine, they would create the herd immunity that would ring-fence and protect the vulnerable, those who had missed out on the vaccination through one reason or other. That way the entire community is protected and further transmission of the virus would cease and the pandemic might be put under control. Building up of the herd immunity through the act of vaccination is possibly the most cost-effective, scientific, morally and politically correct way to fight the coronavirus. The alternative would be to have the community acquire herd immunity through natural infection. Up to 70% or more of the population would have to be infected before herd immunity could be achieved by which time millions could have succumbed to the disease.
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| An electronics technician ( nuclear ) assigned to attack submarine USS Jefferson City ( SSN-759 ) receives the COVID -19 vaccine at Joint Base Pearl Harbor - Hickam 23rd Dec 2020. USN Photo. |
As mentioned earlier, for the civil population in most democratic countries, COVID-19 vaccination is voluntary. This is good as with such high levels of vaccine skepticism and hesitancy, people are given a choice and are not coerced or forced to receiving the vaccine if they do not wish to for whatever reason. However, those serving in the military or other federal or municipal essential services sector like the police or the coast guard or the fire service may not have such luxury of choice when it comes to COVID-19 vaccination. As they frequently have to be in close contact with other people during the course of their work, they are at high risk of being infected. The critical nature of their jobs also means that they cannot afford to be falling sick and be taken off for sick leave for any protracted duration. Many will have to be deployed on overseas missions on land or at sea in regions that may have high rates of coronavirus transmission. Yet others might have the burden of national security on their shoulders, like for example the Gold and Blue crew of the Ohio-Class ballistic missile submarine, who absolutely cannot afford to have a coronavirus outbreak onboard their boat during a several month long nuclear deterrent mission. That is exactly why the members of the Strategic Services get top priority for vaccination in the US military.
Several people in active military service that I have spoken to have either already received the first dose of the vaccine or were told that they would be having it soon, without any options to decline, much as I had expected. For many, it would come as an explicit order from the unit commander : get vaccinated, period.
Global COVID-19 Vaccination Drive
The UK became the first country to approve a stringently evaluated coronavirus vaccine on 2nd Dec and the first in the western world to start mass vaccination on 8th Dec 2020. At the time of writing, the biggest vaccination campaign in the history of humankind is taking place in 66 countries and so far a total of 107 million shots had been administered*. At present the rate of vaccination globally is approximately 4.22 million shots per day. Israel leads the pack with at least 20% of its population vaccinated while the UK and US have each achieved 10% and 7% respectively. With more than a hundred million doses administered cumulatively worldwide and no major adverse events reported, surely logic would tell us that the myriad of COVID-19 vaccines in general are safe.
In the coming days and weeks, more countries will begin their vaccination campaigns, just as more COVID-19 vaccines are being approved for emergency use by the regulatory health authorities. Never in history had so many vaccines been administered in so short a time.
* Around 2nd Feb 2021, the number of vaccinated persons ( 107 million ) as surpassed the number of infected persons ( 104 million ) globally for the very first time since the start of the pandemic. A watershed moment.
The Legacy Of The COVID-19 Pandemic
The impact of the pandemic on every aspect of our life has mainly been negative but one of the rare positive outcome from this global epidemic would definitely be its role in accelerating the advancement in vaccine research and development. If not for COVID-19, who knows how long it would take for the first successful mRNA vaccine to be developed and when we would get our first ever approved vaccine against a human coronavirus disease. Before COVID-19, nobody with the right mind would predict that dozens of vaccines against the same disease could be concurrently developed and successfully achieve regulatory approval in a year or less. Already, a number of winners have appeared among the 150 or more COVID-19 vaccine candidates that started out a year ago. Now the World Economic Forum has an even more ambitious goal of producing a vaccine within 100 days of a pandemic.
While the dust had more or less settled in the race to develop the first effective COVID-19 vaccine, another race had just began. And that is the race between countries to vaccinate as many of their own population as possible. The current challenge is for the manufacturers to churn out vaccines quickly to alleviate the acute shortage that every country faces. It will certainly go a long way to stem vaccine nationalism behaviors that some countries are increasingly exhibiting, like imposing vaccine export controls and vaccine hoarding. But these are mostly things above our pay scale. For the majority of us, we just have to do our part by accepting the vaccine when it comes our way ....
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| COVID-19 ward, early 2020, China. Photo : China Daily |
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| Johns Hopkins Global COVID-19 Map |
Take Home Messages
COVID-19 disease is real and serious. It is not a hoax and it will not go away on its own.
There is still no cure for COVID-19. Existing treatments are merely supportive in nature.
The COVID-19 vaccines approved by stringent regulatory authorities such as the US FDA and the UK MHRA for emergency use are generally safe and efficacious.
The risk of adverse reactions from COVID-19 vaccines are very low and are mostly transient and manageable.
There has been no COVID-19 vaccine related deaths so far. **
Achieving herd immunity through mass vaccination is our best bet to control the pandemic.
Unless vaccination is contraindicated, every eligible person should be vaccinated, if possible.
Get vaccinated as soon as available. Do not wait for others.
Get vaccinated even if there are low levels of COVID-19 transmission within your community. The situation is always fluid and can potentially deteriorate rapidly.
Many of the COVID-19 vaccines continue to demonstrate high levels of efficacy against the new mutant COVID-19 strains and can be readily adapted to deal with future mutations.
Vaccines alone will not put an end to the pandemic. Safe distancing, mask wearing and good personal hygiene must continue to be strictly observed even after vaccination has been completed.
Nobody is safe unless everybody is safe. No country is safe until every country is safe.
Do not believe in everything that you see or hear on the internet or social media. Fact check where necessary and make good use of your critical thinking skills. Believe in science, not rumours. Above all, NEVER drink bleach!
** Update 21 Apr 2021. Unfortunately this is no longer true. The Oxford AstraZeneca and Johnson & Johnson vaccines have been implicated in causing a rare but severe form of blood clotting event characterised by LOW platelet counts. Several have died. Known as vaccine-induced immune thrombotic thrombocytopenia ( VIIT ), it has an incidence of 1 in 250000 vaccinations. This is still way lower than the risk of dying from severe COVID-19 disease, which stands at 2 in 1000 even for a young adult.
This adverse reaction is peculiar to the two vector-based vaccines and are not observed in other vaccine brands such as the Pfizer or Moderna vaccines. The AZ and J&J vaccines are still generally safe to use especially for high risk individuals in communities with high transmission rates and where alternative vaccine brands are not available.
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