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Covishield Vaccine Facts

Covishield Vaccine Facts And What You Need To Know

Updated on May 17, 2024 by Mathukutty P. V.

We are all going through the Covid-19 pandemic. The good news is that many countries have developed vaccines to fight against this disease. Covishiled vaccines have become very famous. This article is about the basics of what is a vaccine, and the phases of trials a vaccine undergoes after it is developed before it reaches the consumer. This article and video detail the current evidence that we have for the Covishield vaccine which is approved for use in India.

Covishield Vaccine Basic Information

Before starting with the Covishield vaccine, let’s have an idea about vaccines. You might have heard the term vaccine, but do you know what is a vaccine, what is the importance of vaccination, and how a vaccine is developed and ready for vaccination in humans? Continue reading and be sure to watch the video to learn the basic information about the Covishiled vaccine.

What is a vaccine?

A vaccine is a product that stimulates a person’s immune system to produce immunity to a specific disease, protecting the person from that disease.

What is vaccination?

Vaccination is the administration of a vaccine to help the immune system develop protection from disease. Vaccination is a simple, safe, and effective way of protecting people against harmful diseases before they come into contact with them. It uses your body’s natural defences to build resistance to specific infections and makes your immune system stronger.

Why is vaccination important?

Vaccination is a safe and effective way to prevent disease and save lives – now more than ever. When we get vaccinated, we aren’t just protecting ourselves, but also those around us.

How does a vaccine work?

Vaccines reduce the risks of getting a disease by working with your body’s natural defences to build protection. When you get a vaccine, your immune system responds.

  • Recognizes the invading germ, such as the virus or bacteria.
  • Produces antibodies.
  • Remember the disease and how to fight it.

Are vaccines safe?

Vaccination is safe and side effects from a vaccine are usually minor and temporary, such as a sore arm or mild fever. More serious side effects are possible, but extremely rare.

References: WHO Vaccines and immunization

Covishield Vaccine Facts And What You Need To Know

Basically, what are vaccines? 

Vaccines are agents that are given to the body to help the body to produce antibodies. So these vaccines can be prepared from components of the organism or they can be prepared from synthetic substances which act as the antigen which is given to the body and the body creates a response to fight against these antigens and through the response, the body produces antibodies which will fight against the actual invading organism if and when someone comes in contact with that organism. So this is what is a Vaccine.

Covishiled vaccine

Now, this form of the causative agent is injected into the body. The body recognises that there is an invasion so it prepares and dispatches soldiers to combat these invasions.  These soldiers are known as antibodies and they destroy the invading enemy which in this case is antigen a causative agent of a particular disease. So next time when the actual disease organism adjourns into the body, the antibodies will return back and destroy them. So while taking a vaccine you are preparing yourself to fight against a particular disease and you are strengthening your immunity. 

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How is a vaccine prepared?

What are the stages a vaccine undergoes before it reaches us so that we can take it?

First of all, the two courses of testing a vaccine are to test first the vaccine for its safety, and second is tested for its efficacy. So one safety warning means to test whether the vaccine has a lot of side effects and whether it has got a lot of adverse drug reactions.

Efficacy means we have to test how effective this vaccine is in preventing that particular disease or preventing the symptoms of that particular disease. So these are the two goals of testing a vaccine.

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What are the phases of testing that a vaccine undergoes?

Now let’s talk about what are the phases of testing that this vaccine undergoes.

Broadly this can be divided into two phases. One is the preclinical phase and the other is the clinical phase.

Preclinical phase

In the preclinical phase this particular vaccine, after it is developed, is tested on animals. We can also call it the animal testing phase. Usually, on animals, the vaccine is tested in rats. The vaccine is administered to the animal and the animal is monitored for safety to make sure that it does not develop any side effects or if it develops side effects, how severe are the side effects?  Second, the test is to see whether this vaccine can produce antibodies in that particular animal. So the vaccine is given to the animal and the animal is exposed to the actual disease-producing organism. And then we see whether the antibodies have been produced and whether the antibodies in the animal can fight against the actual organism. So that is what is happening in the preclinical animal testing phase. Now from the preclinical phase, we move on to the clinical phase.

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Clinical Phase 1

In the clinical phase, there is phase 1. Phase 1, is human trials. Now once we know that this vaccine has been effective and safe in animals, we are going to administer this to humans. What are the criteria? Now the first criteria in others are going to be given on a very small sample size. So let’s say less than a hundred people are going to receive this vaccine. The vaccine is tested again for safety, how many side effects are produced, are the side effects very severe or are the side effects mild, is any adverse drug reaction.

The third is we are going to determine what is the minimum dosing and the maximum dosing of this vaccine. So we are going to see how many vaccines or how much quantity of vaccines has to be given to produce a proper effect in humans. So in this clinical-stage phase 1, we are going to study the minimum dose and maximum dose. And of course, we are going to test the efficacy of the vaccine. So we are going to give the vaccine and then we are going to expose it to the organism and then we are going to see whether they have produced antibodies as was the intent of giving the vaccine. So that is what happens in phase one of the clinical stage.

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Clinical Phase 2

Now next after it has cleared phase one it goes to phase 2. In the phase 2 human clinical trial, we are going to test this vaccine on a larger sample. Let’s say from 100 to 1000 people. So 100 to 1000 people are going to get this vaccine. Again we’re going to check for the side effects of the vaccine on these people, we are going to check whether the minimum and the maximum dose that you determined in stage 1 of Phase 1 is still the same. W

e are going to check the efficacy or effectiveness of the vaccine in producing the antibodies. Now one clear difference between Phase 1 and Phase II clinical is it is one chemical sample; our sample is healthy individuals. We are going to select only healthy people. Now in phase 2 the sample or the people to whom the vaccine is going to be given is going to be mixed demography. Now mixed demography simply means we are going to give to healthy individuals, there are going to be people who have conditions, and there are going to be people from all genders, races, and different age groups about the age of 18. So we are going to give to a heterogeneous population on which we are testing this vaccine. 

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Clinical Phase 3

Next, we go onto clinical Phase 3. Now again we determine that this vaccine is effective and produces antibodies in phase 2 and the side effects are mild that’s not life-threatening side effects. Let’s move on to phase 3 which is again a human clinical trial. Now, this is going to be in a much larger population, there are a lot of demographics so usually, the population is more than a thousand. People from different races, of different gender, different age groups of the age of 18, people healthy, people who are not healthy and already have some other health conditions, everybody falls here.

Again in phase 3 clinical trials, we test the vaccine for its safety that is side effects and adverse reactions, we will also test whether these vaccines are producing antibodies. Now how this is done is once the vaccine is given to all the individuals they left out into the real world. They can go out into the real world, they can go out doing the normal routine activities that they usually undertake. And then what is tested is we are going to test whether they develop any side effects, we are going to do RT-PCR on them and see whether they get infected. So that is basically how the Phase 3 trials.

Covaccine Phases of testing vaccine
Phases of testing vaccine

Approval from the authorities

Now once the drug has begun a Phase 3 clinical trial and it is determined that it is safe to be used and effective in producing antibodies and it is effective in preventing disease in the real world then it goes for FDA approval. 

Now in the present scenario, we thought COVID-19 vaccines, there is a pandemic and it needs to be used on an urgent basis. It does not go to the FDA, it goes to emergency use authorisation (EUA). The emergency use of authorisation is given when there is an agency giving the vaccine. In this pandemic, there is an emergency. So this particular vaccine gets EUA approval. Now in India, two vaccines have got EUA approval. The first one is Oxford University AstraZeneca Covishield Vaccine and the second one is  Bharat Biotech’s Covaccine.

Now AstraZeneca’s Covishield Vaccine is authorised for use in five countries as of now. This vaccine is developed by the University of Oxford in collaboration with AstraZeneca and their Institute of India as the manufacturing and trial partner. Its efficacy was based on 11636 participants from Phase III trials and the analysis has shown that the vaccine was 70.04 % effective in preventing symptomatic COVID-19 occurring more than 14 days after receiving two doses of the vaccine. And the safety data comes from over 20,000 participants across 4 clinical trials which shows that the vaccine is well tolerated and that there are no serious side effects related to the vaccine.

Things that you need to know before you get vaccinated with Covishield

What are certain important things that you need to know before you get vaccinated with Covishield?

Now the purpose of this video, we are going to discuss the Covishield vaccine. What are the things that you need to be careful about, or you need to know before getting a Covishield vaccine?

Covishiled vaccine can be taken by anybody above the age of 18 years. So below the age of 18 years, you cannot take this vaccine Above the age of 18 years the vaccine can be taken.  You must inform your doctor or Health Care provider in case of the following situations.

  • If you ever had a severe allergic reaction to any particular food, any waxing or medication
  • If you have a fever
  • If you have a bleeding disorder or if you are on any medicine such as Aspirin, Heparin Warfarin or any medicine that can cause bleeding. 
  • If you are immunocompromised or any medication that suppresses your immunity
  • If you are pregnant or plan to get pregnant
  • If you are breastfeeding and getting another COVID-19 vaccine

Read Pregnancy And Breastfeeding Guidelines – COVID-19

Covishield is given as an intramuscular injection preferably in the deltoid muscle. So there are two doses of the vaccine each of 0.5 ml and it is given four to six weeks apart. So let’s say we have got the first quarter of 0.5 ml and after four to six weeks we get the second shot of the vaccine. If you miss the 2nd quarter you need to contact your doctor or you need to contact the health provider and inform them about the missed dose.

Then there are certain side effects of this vaccine as it is with all other vaccines, but major side effects or major reactions or life-threatening reactions are very rarely observed in the clinical trial of the Covishield vaccine.

Read How To Self Protect Against COVID-19 – WHO

Reported side effects of Covishield vaccine

Now the side effects reported are that more than 1 in 10 people have tenderness, pain, redness, swelling, itching etc at the injection site. Some people reported feeling unwell, feeling tired, chills, feverish, headache, nausea, joint pain or muscle pain. The commonly reported symptoms are to 1 in 10 people lump at the injection site, fever, vomiting, flu-like symptoms, increased temperature, sore throat, runny nose, cough and chills. Very uncommon side effects are 1 in 100 people reported feeling dizzy, reduced appetite, abdominal pain and large lymph nodes, excessive sweating, itchy skin or rash.

These are all the reported side effects and if you experience any other side effects or experience any other discomforts, it is important that you get to your health care provider and reports those symptoms.

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Covishield vaccine – Commonly asked questions

1. Can you get COVID-19 because you got the Covishield vaccine?

Well, No. You can’t get Covid-19 from the vaccine because the SARS-Cov-2 virus which is the causative agent of Covid-19 is not given in this vaccine. So you can’t get Covid-19 because you get injected with the Covishield vaccine. 

2. Should I get vaccinated?

Another very common question is should I get vaccinated? Well, that is up to you whether you want to get vaccinated or you don’t want to get vaccinated.

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That is about the basic information on the Covishield Vaccine. The most important is self-protection from the Coronavirus. Wear masks, use sanitisers and soap, and keep social distancing and other guidelines from the Govt and health departments. When you follow the guidelines, you are protecting yourself as well as your family and the community.

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Reference: YouTube Rinta Rajan

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