After the world was grappled with the deadly virus in 2020, several countries released the vaccine in January this year. Most countries have been spreading vaccine awareness and many have started their vaccination drives. The vaccines have been introduced only after regulatory bodies have given their assurances regarding the safety and efficacy of the vaccine.
The majority of the news is dominated by vaccine awareness topics lately. While there has already been enough information regarding the vaccines being administered to volunteers, we have begun disseminating the information regarding the manufacturing, working, and production of vaccines to raise awareness and allay fears of the global citizenry.
Today, we will learn about the ingredients of the vaccines and the phases of trials involved before the vaccine was manufactured on a large scale.
Ingredients of the vaccine:
Vaccines are nothing but the weakened or dead particles of viruses and pathogens themselves. But a vaccine is not just that. They contain various other ingredients to make them more efficient and safer. These ingredients have been in use for decades, and each component has a specific purpose of serving. Each ingredient is tested separately to ensure safety before beginning the manufacturing process.
- Antigen: Antigen is a tiny particle of a disease-causing pathogen that acts as an active component in triggering the immune response against the disease. It can even be a whole organism, but it is mainly weakened, inactivated, or killed.
- Preservatives: While some vaccines don’t need preservatives as they are discarded after a single dose as stored in a single-dose vial, some need preservatives to prevent them from getting contaminated. The latter is the case if the vaccine is to be administered to multiple persons. 2-Phenoxyethanol is the most widely used preservative in vaccines and has been in use for decades. It is safe as it has very little toxicity, and hence it is even used in baby care products.
- Stabilizers: As said, there are chances of side effects even after passing the vaccine through multiple safety standards, although minute, due to the chemical reactions occurring within the vaccines. Stabilizers, thus, prevent chemical reactions from occurring within the vaccines to keep the vaccines’ components intact within their places and avoid them from sticking to vials. Lactose, amino acids, gelatin, and proteins are some of the stabilizers which are most commonly used in vaccines.
- Surfactants: Surfactants further prevent the components from clumping and settling. These are most commonly used for vaccines in liquid forms. They ensure that all the components in the vaccine are always blended. They are sometimes used in food items like ice creams too. So, the chance of toxicity of surfactants is almost zero.
- Residuals: These are tiny amounts of particles usually included during the manufacturing or production of vaccines. Residuals are not active ingredients and might be present in the form of egg protein, yeast, or antibiotics. These are present in small quantities as parts per million or billion.
- Diluent: It is a liquid substance used to dilute the vaccines to the required concentration. The most widely used diluent is sterile water.
- Adjuvant: Adjuvants are a tiny amount of aluminum salts included in the vaccine to help improve the immune system’s response to the vaccines. Aluminum doesn’t cause any long-term health consequences as humans ingest it regularly through their diet.
Phases of clinical trials of vaccine:
- Phase 1: Phase 1 of clinical trials includes administering the vaccine to a small number of volunteers to assess the vaccine’s safety and determine the proper dosage. In this stage, vaccines are tested on young and healthy adult volunteers.
- Phase 2: The vaccine is then administered to hundreds of volunteers to ensure its safety of usage on a large section of people. This stage also assesses the vaccine’s capability of triggering the immune response. This stage includes multiple trials to evaluate the efficacy of vaccines on a diverse section of people. The vaccines’ effects on different people are compared to conclude.
- Phase 3: In phase 3 trials, vaccines are used on thousands of populations to determine the efficiency and study the safety in a much larger group. This stage involved administering and testing vaccines in multiple countries and locations to ensure that the vaccine’s performance applies to diverse populations.
In a series of other steps, after completing three phases of trials, the efficacy and safety of the vaccine are reviewed and sent for regulatory and other public health policy approvals. After repeated reviews and approvals, vaccines are released on a large scale.
Even then, continuous monitoring of the vaccine’s performance by recording the effects enables the scientists to track the impact of the vaccine and make adjustments if needed. Hence, vaccines are approved for human usage only after expert monitoring, reviewing, and approval, which guarantees the safety and efficacy of vaccines. It is important to raise vaccine awareness and get vaccination done in order to fight with the pandemic.