Vaccination: the light at the end of the tunnel

The COVID-19 pandemic has changed the world as we know it. The strict public health measures and the government’s response to the pandemic are still not enough to stop the grief COVID-19 has brought us in the form of our broken families, shattered economies, desperate people, and generations’ worth of damage. Life cannot go on the way it has been for the last ten months. An effective way to recover from this damage is through vaccination. I hope to encourage people to take the vaccine by providing insight into the newly released Pfizer-BioNtech and Moderna vaccines and debunking the myths associated with it.

Vaccination can only be understood when we have some background knowledge of the structure of the virus. Coronavirus, also known as SARS-COV-2 virus, was first detected in Wuhan, China in late 2019. It is known to have crown–like “spike” proteins on its surface that are complementary in structure to one of the receptors in our cells (known as ACE2). The “spike” protein on the surface and the receptor bind to each other, resulting in the onset of the infection. Vaccination is the process where we are exposed to an inactive form of the foreign infectious agent (“spike” protein), which stimulates our immune system (mainly T and B cells) to fight against it without getting infected. This also results in immunological memory (this means that our body can fight off the infection if we are exposed to the same infectious agent again in the future, as meant by the word “memory”). A vaccine is only administered to healthy individuals. Now that we have a vaccine with us, it’s the implementation that comes next.

The Canadian government’s strategy of implementing the vaccine and having the whole population vaccinated will play a key role in helping the population to achieve immunity. The Canadian government received 249,000 Pzifer doses by the end of December 2020, with their target population being the most vulnerable groups, health care workers, and  the elderly. Canada currently expects six million doses of the Pzifer vaccine to arrive by the end of March 2021, which is considered to be enough for three million of the 38 million people in Canada. The general immunization will begin in April 2021, as stated by Health Canada. While the government is still in the process of strategizing a well-thought-out plan, the government hopes to get the whole population covered by the end of the year 2021.

Although it is true that the government hopes to get the whole population covered by the end of the year, having only three million out of the 38 million populations being vaccinated after the end of the first quarter of 2021 clearly shows that not each and every individual in the population will have access to the vaccine by the end of this year. Thus, this raises the question of how the whole population could achieve immunity as by the end of the year, if not everyone will have access to the vaccine. The concept of herd immunity might help us to answer this question.

Herd immunity is the indirect protection from infectious disease provided to non-immunized individuals when vaccination levels in a community are relatively high. In a sufficiently vaccinated population, herd immunity lowers the probability of contact between a non-immunized individual and an infected individual, lowering the amount of virus spread in the whole population. As a result, it helps to ensure that vulnerable groups who cannot get vaccinated are kept safe. A herd immunity threshold has to be achieved in order for the herd immunity to take effect, where the proportion of individuals who are immunized exceeds one-one/Ro. This is based upon the simplest model of herd immunity where Ro is the number of secondary infections caused by one single infected individual. Suppose we assume an R estimate of two for SARS-COV-2 (on average, each infected individual will give rise to two other infections), our herd immunity threshold will be approximately 0.67 or 67 percent. Thus, the proportion of immunized (vaccinated) individuals must exceed 0.67 for herd immunity to take effect. This model relies on simple assumptions such as homogeneous population mixing or uniform sterilizing immunity in recovered individuals, which can be quite hard to obtain in a real-world population. The real-world population is far more complex than the simple population as discussed above, due to variation in population structure, transmission dynamics in the population, and weakened immune systems. This basic model is better off to be used as a rough estimate for the number of Canadians needed to be vaccinated to reach herd immunity. International travels must remain banned for it to take effect.

The problem that arises in vaccine distribution is having the vaccine delivered at the correct temperature—in the case of the RNA vaccine its -70 degrees Celsius. While the company ensures that enough of the vaccine will be produced and delivered at the right temperature, only time will tell if they are successful. Questions still arise, such as if enough people will be willing to be vaccinated in order to exceed the herd immunity threshold. Do people have faith in the World Health Organization (WHO) and other health agencies  which state that the vaccine could cure them?

The public needs to be well educated on vaccines by dispelling the myths and fear surrounding them, which will ensure that enough people will be willing to be vaccinated. The first common myth is that often prevents people from vaccination is believing that a link exists between the MMR vaccine (which provides overall immunity against measles, the mumps, and rubella) and autism, when there isn’t. Andrew Wakefield, an English gastroenterologist, published a paper in 1998 about this myth in the medical journal Lancet. However, his theory defied immunological concepts so it is widely accepted as false information. People might also neglect to take this vaccine due to the belief that the COVID-19 vaccine preparation was rushed. The technology that underlies the production of this vaccine has been in the development process for decades and has been used as a preparation for pandemic situations such as COVID-19. The approval of any vaccine takes into consideration its side effects, any apparent adverse effects, as well as the length of time it provides immunity. There are many potential ways for the public to be educated; this involves publishing correct information in newspapers, broadcasting the benefits of vaccination in news channels, and thorough discussions of the topic in podcasts and on social media such as Facebook and Twitter. Since our generation is heavily involved with technology, it can be used as a source for dictating the actual science behind vaccines and build up the faith between the people and the health agencies.

While the future is still uncertain, it is important to acknowledge the hard work of those plugging away endless hours in hopes to change our current abnormal reality. COVID-19 has had many adverse effects in the whole world, but it will serve as a meaningful point in history and have us better prepared for any infectious disease that could occur in the near future.