Common Questions About COVID-19 Vaccine Answered


With great perseverance from multiple health professionals and the combined diplomatic efforts of national governments, the roll-out of various COVID-19 vaccines have already begun. However, the uncertainty of its medical credibility is now a real problem.


If you find yourself second-guessing whether you’re willing to sign up to get your first COVID19 shot or still weighing its pros and cons, you’re not alone. Even with the many success stories of families being united or talks of the travel industry opening up once more, many people still aren’t sure.

At present, the US government has laid down the groundwork for the rapid development of vaccines against COVID-19 with the importance of relying on new technologies. As they are one of the world’s largest distributors and manufacturers of the vaccine, they have 4 candidates in phase 3 studies that have become the bedrock of a COVID-free future. 

At this crucial part of the process, providing evidence-based information is almost as vital as ensuring everyone in the world gets their dosage. In the age of fake news and fear-mongering, an environment of polarization and mistrust can easily take hold of society. The Centers for Disease Control and Prevention have issued a statement regarding which facts to be true and not in regards to the vaccine.

One of the medical doctors from Boston Medical Center’s Home Care Program, Dr. Won Lee, says on this matter: “There’s so much misinformation out there, and it’s hard for anyone to know what to believe.”

With that, here are some common questions patients are likely to ask about COVID-19 vaccines.

  • Does it matter which type of COVID-19 vaccine I get?

With the different COVID-19 vaccines already approved and have been distributed, they can be distinguished from each other depending on the technology used. There are “classic vaccines”, for instance, which use whole inactivated virus or viral proteins. Then there are those on the other end, using more advanced technologies to introduce the body to a specific gene sequence with the right steps so that it can produce a given viral protein. This genetic information can be introduced directly into the cell (messenger RNA vaccines) or via a viral vector that infects the cell but does not replicate. 

mRNA vaccines, the ones that are introduced directly, include the already approved Pfizer-BioNTech and Moderna vaccines. Viral vector vaccines include the Oxford/AstraZeneca vaccine, the Janssen (Johnson & Johnson) vaccine, and the Sputnik vaccine by the Gamaleya Institute. 

All of them have been tested in people to prove their safety and efficacy throughout the three phases of clinical trials, and so have been proven to be effective in protecting the body from latching on to the virus.

  • How do the vaccines work?

In a nutshell, the messenger RNA vaccines introduce a gene sequence into our cells that codes for protein S, which is a SARS-CoV-2 specific protein (aka the one that will help your body be immune against COVID19). These vaccines contain genetic material synthesized in the laboratory that makes cells react and make copies of said protein S. 

The immune system will then recognizes protein S as foreign and retaliates by generating specific antibodies to ward off the intruder; therefore, when the coronavirus should enter the body, it will already have immunity from it.

Pfizer / BioNTech, and Moderna

These vaccines are based on mRNA. They are the ones to provide the cells with the genetic sequence that codes for the S protein of SARS-CoV-2. In simple terms, the genetic material contained in these vaccines, essentially, gives the cells instructions on how to produce the protein by producing S-specific antibodies that can fight off the dangerous infections from the virus.

Oxford / AstraZeneca and Johnson & Johnson (Janssen)

These vaccines introduce a harmless virus into the cells to, once again, introduce the genetic instructions on how the body can produce the SARs-CoV-2 S protein. The adenovirus (the harmless virus introduced) is called a viral vector and has been genetically modified in the laboratory so it can infect the cells, but will not replicate. The Oxford/AstraZeneca vaccine introduces a chimpanzee adenovirus. For the Janssen one, it carries a modified human adenovirus called the Ad26.

  • Are they safe?

Thanks to the many technological advancements over the past year in lieu of urgency, COVID-19 vaccines have been developed in record time.  However, this does not imply that the process was not rigorous and that the usual steps were not followed. 

Each approved vaccine went through the motions and jumped through the hoops, and underwent all three stages of clinic trials: assessing for the safety of the drug, testing its efficacy, and randomized and blind testing.

Therefore, all vaccines approved by the regulatory agencies are undoubtedly safe and when vaccination campaigns began, tens of thousands of people have already received the vaccine during clinical trials.

  • Will it change my DNA?

Since the vaccine works by essentially injecting another virus into your immune system, that notion alone raises a few brows and have more people hesitating. However, this is how most antibody vaccines have always been made: it basically offers an instruction manual that teaches your cells to recognize and fight the virus.

The messenger RNA doesn’t have access to the nucleus of our cells, too, so it cannot be incorporated into the DNA markup of humans.

“The vaccines do not interact with your DNA in any way,” Dr. Lee explains, “They contain no live virus. You will not get COVID from this vaccine.”

  • Is there still a risk to contract COVID-19 even after I have been vaccinated?

While most advanced vaccines have shown an efficacy rate of above 90%, no vaccine is truly 100% effective. There is still a slight chance you may fall sick with it despite being vaccinated, because virologists and immunologists alike have spoken of the unintended mutation and evolution of the virus.

A great majority of vaccinated people will be protected against the disease, or against severe forms of the disease. Prevention is first and foremost always the best treatment, and getting vaccinated will significantly lessen your chances of coming into contact with COVID-19.

  • Will I get sick from the vaccine? What are the common side effects post-vaccination?

The vaccine is introduced into the body itself, but its genetic material. There are some side effects the day after, as with any vaccine, such as feeling fatigued, pain in the arm, or headache. But these are all signs that your immune system is responding to the agent.


While the rest of the world has celebrated and rejoiced in the global effort to expedite the vaccine distribution and implementation, there are still those who have one foot out the door or are simply waiting for the other shoe to drop. There have been those who questioned the corners that were cut, protocols that were bypassed, and the likes.

With this post, we hope we were able to ease some of the uncertainties regarding the vaccine.

The views expressed in this article are those of the authors and do not necessarily reflect the views or policies of The World Financial Review.