How COVID-19 Vaccine Works & How Vaccine Distribution works in India: -

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In this COVID pandemic, it becomes really important to be safe and healthy cause this CORONA Virus can be very fatal for human health. So, there are some ways which can help us to prevent getting this disease.

• Keep Social distance from others.
• Wash hand frequently or sanitize hands at regular intervals.
• Wear a Mask.
• Stay home, don’t go outside until it is not necessary.
• Get Vaccinated.

Here we will talk about how Vaccination works, how vaccination prevents or helps us to fight this COVID pandemic generated by CORONAVIRUS. Right now, each and every country have only one main concern, which is to get Vaccinated for their countrymen. All the vaccines available in various countries are safe and they work by training the human immune system against future infection. These vaccines don’t cause any kind of disease. There may be some small side effects of these vaccines such as Vomiting, headache, fatigue, Fever etc. Every vaccine developer has worked really hard and under pressure to develop a Vaccine for COVID-19 CORONAVIRUS (SARS-CoV-2 Virus).

These vaccines have been developed from different-different sources and technology. All these vaccines serve the same purpose which is to protect from COVID-19. Some of these vaccine manufacturers used the SARS-CoV-2 virus, some used only part of it and some manufacturers don’t use any material derived from the virus. So largely we have the below-mentioned vaccines types -

• Viral Vector Vaccines
• mRNA Vaccines
• Inactivated Vaccines
• Subunit Vaccines

How our Body fights Disease:

First to understand how all these COVID-19 vaccines work we have to first understand how our body fights the disease, when the virus, bacteria attack our body. When a virus attacks a human body, it multiplies quickly which is known as infection, this infection causes the diseases. In our blood, there are several tools such as red blood cells, white blood cells etc. Red blood cells carry oxygen to all the tissues of the organs and white blood cells fight infections.

• Macrophages are known as white blood cells which eat up and digest germs and dead cells. These macrophages leave a part of the invading germs called antigens. Our body thinks of these antigens as dangerous and generates antibodies to fight them.
• B-lymphocytes are defensive white blood cells. B-lymphocytes produces antibodies that attack the pieces of the virus left behind by the macrophages.
• T-lymphocytes are another type of defensive white blood cell. They attack cells in the body that have already been infected.

When a healthy person comes in contact with the COVID-19 virus, it takes some days or a couple of weeks for that body to get over the infection. The immune system of the body remembers this and learn how to fight against that disease.

The T-lymphocytes known as memory cells take action quickly when they come in contact with the same virus again. When the familiar antigens are detected, B-lymphocytes produce antibodies to attack them.

Viral Vector Vaccines: -

This Vaccine doesn’t contain the whole SARS-CoV-2 Virus. In this technology, the manufacturer uses a harmless virus that can allow our cells to make spike protein. Manufacturer like Oxford-AstraZeneca, Sputnik V uses Viral Vector in their COVID-19 Vaccines which uses different-different adenoviruses as the vector. These Adenoviruses can generate the common cold. The Oxford-AstraZeneca vaccine has a chimpanzee’s adenovirus vector commonly known as ChAdOx1. The Russian Vaccine Sputnik V uses two different-different human adenovirus vectors commonly known as Ad26 & As5. These vaccines have the genes for the spike proteins and deliver this into cells after vaccination. Then these cells make the spike protein and present it to our immune system. They also can’t cause COVID-19.

mRNA Vaccines: -

Pfizer-BioNTech and Moderna have developed the First mRNA vaccines for the human after clinical trials for COVID-19. mRNA vaccines don’t have any part of the SARS-CoV-2 Virus. These mRNA vaccines have a chemical synthesis messenger mRNA which contains the necessary information to generate Spike Protein. Our cells in the body generate these spike proteins which presents in our immune system and creates antibodies & long-lasting immunity in the form of T cells and B cells.

Inactivated Vaccines: -

Inactivated Vaccines contains the entire SARS-CoV-2 Virus, though this virus chemically modified and inactive. Bharat Biotech uses a chemical known as beta-propiolactone to inactivate the SARS-CoV-2 virus in the Vaccine. The chemical used in this process modifies the virus’s genetic material. The immunity we get from this vaccine is not long-lasting, so manufacturer use adjuvants in their COVID-19 vaccines for a stronger Immune system. To achieve this, it is necessary to receive booster shots after getting an inactivated COVID-19 vaccine.

Subunit Vaccines: -

This vaccine uses only part of the SARS-CoV-2 virus and these vaccines also provide the protein directly. NOVAVAX COVID-19 vaccine is an example of a Subunit Vaccine. Scientist grows these spiked proteins in the lab. For this purpose, insects’ cells are used to grow the proteins before purifying them. Later this protein form nanoparticles, to get a strong immune response NOVAVAX to add an adjuvant (A chemical that stimulates the immune system)

The distribution system of COVID-19 Vaccines in India:

• In the first couple of phases, the centre procured the entire quantity of the vaccines from the Serum Institute of India and Bharat Biotech and later it distributed it to the states. Then states distribute the stock to the government vaccination centres. But from 1st May centre will procure only 50% vaccines from the manufacturer and remaining 50% will be for open markets.
• In India, the Vaccination drive was launched in several phases.
• In its First Phase, all the health workers and frontline workers were vaccinated, this drive started on 16 Jan 2021.
• In Second Phase all the senior citizens and people who are above 45 years of age, this drive was launched from 1st March 2021.
• In the Third Phase, all citizens who are above 18+ age is going to be vaccinated from 1st May 2021.
• In India Covaxin and Covishield Vaccines are used for the vaccination and recently Sputnik V is also got permission from the Indian government. These all three vaccines are stored between 2–8-degree Celsius temperature.
• In India, a digital platform called Co-WIN tracks vaccine stocks, storage information and identifying beneficiaries. Co-WIN is an indigenously developed technology that provides real-time information on vaccine stocks and storage temperature across all cold chain points in the country. This project aims to regularise the vaccine flow network by ensuring data-driven and efficient management of the immunisation supply chain.