All you need to know about Effectiveness of COVID-19 Vaccine

Are COVID-19 Vaccines worth your time, money and health investment? Do you want to know which of the vaccine will be more effective for you? What does research suggests about COVID-19 Vaccine effectiveness. This article will answer and clarify every single doubt you have regarding COVID-19 vaccine effectiveness.

Introduction to COVID-19 Vaccine’s effectiveness and usage

The outbreak of COVID-19 generated a massive economical and healthcare crisis globally. Many countries with advanced biomedical fields and secure health systems have already joined the race for inventing an operative and effective vaccine.

With the spread of this unprecedented pandemic, researchers across the world have participated in the conduction and performance of different treatments.

Their attempts included Plasma transfer therapy, repurposed antivirals, and different drug prescriptions.

World Health Organization (WHO) has viewed vaccination to be an effective way of stopping the further spread of COVID-19 and considered it as an efficient method to cure and prevent this contagious disease.

The UK successfully initiated a program for the implementation of COVID-19 vaccines in order to determine vaccine effectiveness. The Program already included the use of the Pfizer-BioNTech messenger RNA(mRNA) vaccine and BNT162b2. The UK expanded it with the addition of several other vaccines such as Oxford-AstraZeneca adenovirus vector vaccine and ChAdOx1-S.

A new variant of COVID-19 was discovered in southeast England. This specific mutated version proved to be more dangerous than its first strain. The contagiousness of this strain can be measured by observing its mode and speed of transmission. This particular problem raised many concerns among the researchers regarding vaccine effectiveness. So now that we understand about the upcoming hazards and their treatment via an effective vaccine, let’s dive right into their importance and effectiveness.


With the development of a safe and effective vaccine, researchers would be able to treat this virulent disease in no time. Fortunately, the developmental process has already begun globally. 115 candidates participated in this race and only eight candidates were able to perform Phase 1 and Phase 2 clinical trials.

The only way to prevent yourself from infection is to get vaccinated. It also provides a great deal of help for those who are already infected as it increases the effectiveness of natural immunity. Hence, the need of getting yourself vaccinated is mandatory.

The current status quo of these vaccines has been proven significantly effective against (SARS-CoV-2) strain. Different clinical trials are performed before its provision towards public use. These clinical trials approved seven vaccines for further civilian use. Getting yourself vaccinated will not only prevent you from (SARS-COV-2) but you will also be able to protect other people around you from infection.

To stop this pandemic and continue living a normal life we have to adapt to all the social and healthcare requirements. With the ending of COVID-19, society will once again initiate its economical, educational, and healthcare activities without any restrictions and health hazards.




With the spread of the COVID-19 pandemic like a wildfire, the vaccination development authorities expedited their activities. . (Le, T. T. et al 2020).

You might be thinking how can we determine different vaccine’s effectiveness, well worry not. Here we have explored several research studies and found out the most effective vaccine’s descriptions.

Research suggests that vaccines that are mRNA-based Pfizer are about 95% effective. This does not mention the fact that the other 5% will remain unprotected and will eventually get infected. This is a common misconception regarding such vaccine’s effectiveness. It means that the risk factor among those people who get vaccinated will be decreased up to 95%.

Natural immunity acts as a very weak barrier for the entrance and combating of (SARS-CoV-2). When this specific virus enters our immune system, it causes several life-threatening situations, such as causing both pulmonary and systematic inflammation that can eventually lead to multi-organ dysfunction.

The ability of our innate immune memory helps out this subsequent virus in getting immunity because of its nonspecific protections.

A recent research study was conducted regarding the determination of COVID-19 Vaccine effectiveness on different animal occupants such as transgenic mice, primates (non-human), and other animals such as ferrets and hamsters were tested for the said cure, but after several experimental trials, it was confirmed that these animals are the least susceptible ones towards COVID-19. These animal models were improved with time after major assessment and experimental techniques. New and prevalent viral strains were planted and their immunity towards newly formed vaccines was observed.

After several experimental and clinical trials, remarkable progress has been observed.

The efficacy of a vaccine is shown with the help of its effects on mild to severe symptoms of COVID-19.

So what are the frequently used vaccines throughout the World? Which one is more effective?

Vaccinations that are used globally mainly include Pfizer-BioNTech and Oxford-AstraZeneca.

A study conducted assumed the effectiveness of COVID-19 vaccines on different age groups before and after the research study. Results of pre and post vaccinations in those particular groups were calculated and assessed. Groups containing 80 years old participants were vaccinated with BNT162b2. This group had higher possibilities to be tested COVID-19 positive after 9 days of vaccination. Groups that were targeted at the beginning were more prone to this infection.

The comparison between mentioned vaccinations was conducted and their impacts on human immunity were observed after 10 to 13 days (Lipsitch, M. and Dean, N. E. 2020).

Anyhow, after the 14th day of the vaccination trial, their effectiveness rose to 89%.

In another research study regarding COVID-19 vaccine effectiveness different groups containing participants of 70 years old age were turned to get vaccinated and they were showing uniformity of symptoms with the former group.ChAdOx1-S vaccinations were given to these groups and their results were noted to be projecting upwards. Their effectiveness was shown to be 60% and increasing up to 73% after 28 to 34 days.

Moreover, groups that received one dose of BNT162b2 were less prone towards contagiousness and death risk, while groups that received one dose of ChAdOx1-S showed a reduction in death risk for about 37%. both of these vaccines were proved to be efficient and effective against COVID-19 for about 80%.

The results were quite prominent when both of the mentioned vaccines were deemed to be successful towards the symptoms of (SARS-CoV-2).

Phase 3 clinical trials on different vaccines are still in process and to expedite its effectiveness, innovative and unique features have to be designed.

Research clearly shows the accelerated amount of elderly people affected with COVID-19.

A safe and effective vaccine can lead to elderly protection in two different ways.


1) Direct protection


2) Indirect protection


Direct protection includes those groups that are at higher risk of getting infected. These groups are vaccinated to provide them a shield against contagiousness.

Indirect protection includes those people who are in constant contact with higher-risk groups. Such people are also vaccinated to prevent their further spread.

We all are familiar with the age-structured mathematical strategies regarding the use of vaccinations. These strategies are applied by several governments to make sure that vaccines are used in a proper and organized manner. However, the main purpose behind this strategy is to decrease wastage and increase its proper usage.

But the deployment of these vaccines has been increased since its massive production on a global level. When an extended amount of these vaccines are provided to the civilians. Accordingly, the mathematical strategies will probably change in terms of their distribution and protection among several age groups.

The main reason behind the Phase 3 efforts is to ensure individual-level safety.

First trials are merely conducted to determine COVID-19 vaccine effectiveness that include safety and protection for subgroups. However, their performance ratio is far better when applied in the field of high-risk groups and avoids the idea of high protection strategies.(Kim, J.H., Marks, F., and Clemens, J. D.2021).

The main question that is mostly asked by many people is that what exactly vaccines do? Do they reduce virulent contagiousness or prevent infection?

To answer these questions we must first recognize indirect protection. To understand this phenomenon, different research studies should be conducted for data generation and collection.

WHO’s Solidarity Vaccine Trial

Their main purpose is to Protect the essence of placebo-controlled follow-up. Anyhow, follow-up may last for up to 12 months or more, in case of local deployment of vaccinations.

To provide earlier protection to the high-risk groups but at the same time, it may also be considered as unethical jargon to ask participants for trying every available vaccine.

Phase 3 trials will eventually identify the ideal and effective vaccine to deploy among civilians. After the main step of deployment is carried to an end, the follow-up step will include the post-assessment of vaccine effectiveness.


These trials may include several levels of sub trials such as


1) Individual-level randomized trials

2) Community-level randomized trials


Some of the Phase 3 trials that were conducted to determine COVID-19 vaccine effectiveness, examine and study the viral shedding duration, to recognize and assess the impact of contagiousness. Moreover, the examination of viral shedding can be performed in an artificial environment such as Laboratory settings.

Although many vaccines are developed with different attributions to treat COVID-19, still having enough knowledge about direct and indirect protection can verily help us to generate several strategies regarding effectiveness of COVID-19 vaccines and their usage.



A recent survey showed that during the lockdown, many citizens of France have refused to get themselves vaccinated. The citizens who showed resistance towards COVID-19 vaccinations were estimated to be about a quarter 26% of the adult French population because they were skeptical and doubted the vaccine’s effectiveness.

After several efforts of the researchers, its effectiveness was confirmed and it has been approved for the citizens finally..

Moreover, If 63% of nurses with 50% efficacy in Hong Kong intended to take the COVID-19 vaccinations, it means that the promotion of the effectiveness of COVID-19 vaccine among the general civilians will be more challenging than it seems. (Kwok, K. O et al, 2021)



After several pieces of research and data collected from different articles and subjects, it is ultimately proved that vaccination is the only solution to this lethal and deadly (SARS-COV-2) virus. The quality and range of vaccines have been evolved after many trials and laboratory tests. Now the highly effective and wide-range vaccines covering different strains of COVID-19 are available in the market. But due to some rumors and false information revolving around it has been observed that the general population usually shows resistance against COVID-19 vaccination to prevent themselves from the supposed side effects. Many surveys and analyses now prove that the COVID-19 vaccine shows very mild and short-range side effects and hence highly proficient and effective for the general population.


Kwok, K. O., Li, K.K., Wei,W.I., Tang, A., Wong, S. Y. S., and Lee, S.S. (2021). Influenza vaccine uptake, COVID-19 vaccination intention and vaccine hesitancy among nurses: A survey. International journal of nursing studies, 114,103854.

Kim, J.H., Marks, F., and Clemens, J. D. (2021). Looking beyond COVID-19 Vaccine phase 3 trials. Nature medicine 27(2), 205-211.

Lipsitch, M. and Dean, N. E. (2020). Understanding COVID-19 vaccine efficacy. Science, 370(6518), 763-765.

Le, T. T., Cramer, J. P., Chen, R., and Mayhew, S. (2020). Evolution of the COVID-19 vaccine developmental landscape. Nat Rev Drug Discov, 19(10), 667-8.