It has been a roller coaster eighteen months for many of us as we try to navigate through the many questions and opinions surrounding the Covid pandemic. The hope of this article is to answer some of these questions from the view of a scientist. I have been working in the field of vaccine development for almost twenty years and recognize this as a complex process that requires a team approach from many experts. As we enter a new phase of greater freedoms during this pandemic many of us have a yearning for things to get back to normal. We want security in our future and to regain what was lost during the previous year and a half. Yet, we are faced with conflicting news about new variants, vaccination safety, new outbreaks, and increased death rates globally.

Some people have strong opinions as to whether it is safe or not to get a vaccination and may use medical terminology (sometimes out of context) to a point. Even those of us who are well-versed in medical terminology find ourselves having to refresh our vocabulary in immunology, virology and epidemiology as new information concerning the mechanisms of Covid-19 become available through ongoing research efforts. For those who are not in daily contact with these terminologies, receiving said information can become confusing and overwhelming.

For instance, what are viruses and why and how do they mutate? In short, a virus is a small agent (some would not even call it an independent life form) that needs to infect living cells in order to replicate. During this process, viruses frequently kill the cells they infect, setting off a cascade of negative immune responses in our bodies. Unfortunately, because viruses are vastly different from bacteria, they cannot be killed by medications such as antibiotics.

Since a virus is a collection of genetic codes, (in the case of Covid-19, this genetic code is called RNA) which is surrounded by protein, it can adapt by mutating its genetic code to try and outsmart the host body’s immune response. Each time a virus replicates, it has the possibility to mutate. The more people it can infect, or the longer it can stay in a host without being destroyed, the higher the probability of it mutating and ultimately changing into a new variant such as the Delta variant we have heard about a great deal lately. The formation of a new variant through mutation is especially possible in the case when Covid-19 infects chronically ill patients such as those suffering from HIV/AIDS or tuberculosis.

Fortunately, our bodies have a defense mechanism – the immune system. One way to think of your immune system is to imagine a small army comprised of soldiers with different specialties. When a pathogen (any substance that can make one sick) such as the Covid-19 virus enters our bodies, our personal army goes into full defense, deploying its most common soldiers – the white blood cells. The white blood cells on the front lines are called macrophages, they spring into action defending our bodies by gobbling up anything they recognize as foreign. After they kill the invading virus, they leave behind parts of that virus’s proteins called antigens. Our bodies then identify said antigens as dangerous and stimulates antibodies to attack them. Our second line of soldiers are B-lymphocytes. They are the ones who produce the antibodies that attack the antigens. To further defend us, we also have T-lymphocytes. These little soldiers kill cells in our body that have already been infected. There is also a type of T-lymphocyte called memory T-lymphocytes that memorize each “attack” or infection so that our bodies can spring into action quickly if the same virus is encountered again.

It can take some time (days to weeks) for our bodies to deploy all the defense mechanisms needed to help us get over an infection. Unfortunately, as with Covid-19 in some cases, there could be so many virus particles (viral load) that our soldiers get overwhelmed by the enemy and we get sick or could even die. If our body has been given a proper warning, it has a far better chance to activate our immune system in a timely manner to fight the virus. This is where a vaccine comes in. Fortunately, Covid-19 vaccines help our bodies develop immunity to the virus without us having to get the illness. Although once we get the vaccine, it can take a few weeks for the body to produce T and B-Lymphocytes that helps to protect us.

There are three types of vaccines that can activate our immune system against Covid-19 – mRNA, vector, and protein-subunit vaccines. Remember that none of these vaccines can give us Covid-19 because none of them contain the full genetic code for Covid-19, they only utilize specific parts. The newest type of vaccine is the mRNA vaccine. These vaccines contain a tiny part of RNA, which scientists have synthesized (created) in a lab from one of Covid-19’s spike proteins. This vaccine tricks the body into thinking that it is under attack because an unrecognized protein is being introduced. This activates the T and B-lymphocytes in our defense system which both allows our bodies to remember Covid-19 and go through the process of making antibodies to fight it. Another group of vaccines is called vector vaccines. These vaccines contain a harmless, weakened form of a live virus other than the Covid-19 virus. It then has a small part of the Covid-19 virus inserted through genetic engineering into the live virus’ genetic material. Once someone gets this vaccine, their bodies make copies of the protein from the tiny Covid-19 particle which sets off the process in our bodies to build T and B-lymphocytes to protect us in the future in case we get infected with the real Covid-19 causing virus. There is also a type of vaccine called protein-subunit vaccines. Similarly, to the mRNA vaccine, this vaccine only contains a small piece of Covid-19’s proteins. After vaccination our bodies respond to these unfamiliar proteins and are tricked into making T and B-lymphocytes that would protect us if we were ever infected with the real Covid-19 causing virus.

After getting any of the abovementioned vaccines, our body is left with an arsenal of memory T-lymphocytes as well as B-lymphocytes that are armed with the right information to fight the virus when we are exposed to it in the future. If enough of us take the vaccine, it eventually has nowhere to go and the pandemic could hence be controlled, this is known as herdimmunity. Unfortunately, a great deal of misinformation has made it into social media that causes people to be hesitant in taking the vaccine. It is normal for one to have symptoms such as a sore shoulder and light fever after taking a vaccine. It is a positive sign that our body is activating its immune system. Also, important to know, is that one is not immediately immune to the virus after getting the vaccine since it takes time for the body to manufacture those T and B-lymphocytes. It is possible to be infected with the virus just before or after the shot and it is therefore important to maintain social distancing and other safety measures until our immune response kicks in. Most of the current vaccines also require two shots. The first shot is to start building up our body’s defense and the second is to make sure we have the most protection possible from the vaccine.

Vaccines typically take many years to develop due to finding funds, getting authorizations, ethics permissions and determining manufacturing and distribution. For Covid, due to large investments from governments and philanthropic organizations across the world, the world’s top scientists and researchers were able to start working immediately and collaborating internationally. Because of the severity of the pandemic and because so many people were dying from the disease, approval for each stage of development was prioritized or researchers were given enough resources to assist with animal ethics approval to volunteers for human trials. Typically, researchers spend months or years finding funding or searching for enough trial participants to have statistically significant data to analyze. Because the prevalence of Covid-19 is so high, it was easy for researchers to find thousands of volunteers, and it is easier to track if those volunteers get sick, therefore allowing vaccine trials to be conducted on a faster timeline. In addition, international pharmaceutical companies increased the capacity for vaccines to be manufactured and distributed in large-scale quantities.

We are together in this pandemic. Therefore, as many of us as possible need to build immunity by taking the vaccine. Only then can we achieve our much-needed herd immunity. Just like our T and B-lymphocytes are “soldiers” collectively working together to defend us, we are also “soldiers” who need to work together to defend our communities. Getting a Covid-19 vaccine is one of the most important steps in taking action so that business can reopen, schools can be a safe place for our children, and so we can enter into a world post Covid-19. In the meantime, wearing a mask, washing our hands and maintaining social distancing can buy us time to help reduce our chance of exposure or transmitting it to friends or loved ones.

Ena (Christina) M. Bromley, Ph.D., M.Sc. Dr. Bromley is trained as both a statistical geneticist, genetic epidemiologist. Ena has been contributing to regulatory agencies along with biotech and large pharmaceutical companies in establishing criteria towards precision medicine and targeted therapeutics for complex disease. She has provided her expert opinion in the design, analysis and interpretation of complex data. This include representing companies towards regulatory approval for vaccines, drugs and medical devices. Dr. Bromley also serves as representative on various data safety monitoring committees. Due to the urgent need for expert analytical knowledge of vaccine studies and the development of therapeutics, she has provided her expert opinion for various clinical studies involving SARS-CoV-2 (COVID-19). Previously Dr. Bromley was involved in advising vaccine and therapeutic studies for Ebola, Plague, Rabies, Influenza among an array of infectious diseases. Dr. Bromley is also an active member of ICODA (The International Covid-19 Data Alliance).

Dr. Bromley is an analytical expert, sought after for her broad analytical knowledge across a wide range of therapeutic areas and her ability to combine genetic, analytical and epidemiological factors in the decision process towards targeted therapeutics, vaccine development and drug discovery. Her passion is to provide expertise towards actionable execution of scientific knowledge in clinical studies. Dr. Bromley resides in Nederland, Colorado, and is active in the Nederland Community Center and Nederland Community Presbyterian Church.