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June 20, 2021

Types of Covid 19 Vaccines

Types of Covid 19 Vaccines

1)    RNA vaccines  

A ribonucleic acid (RNA) vaccine or messenger RNA (mRNA) vaccine is a type of vaccine that  teach our cells how to make a protein—or even just a piece of a protein—that triggers an immune response inside our bodies. That immune response, which produces antibodies, is what protects us from getting infected if the real virus enters our bodies. It uses a copy of a natural molecule called messenger RNA (mRNA) to produce an immune response. Once inside the immune cells, the vaccine's RNA functions as mRNA, causing the cells to build the foreign protein that would normally be produced by a pathogen (such as a virus) or by a cancer cell. These protein molecules stimulate an adaptive immune response which teaches the body how to identify and destroy the corresponding pathogen or cancer cells.

. Instead of introducing the body to an inactivated or weakened version of a virus or a piece of it, they temporarily turn the body’s cells into tiny vaccine-making factories.

 

Pfizer–BioNTech

Moderna

Curevac

Walvax

Brand Name

Comirnaty

mRNA-1273

 

 

Company

Pfizer, America and BionTech, Germany

Moderna, America

Germany

China

 

 

 

Not effective

 

 

  • First, most negative effects occur within 6 weeks of receiving a vaccine, which is why the FDA asked the companies to provide 8 weeks of safety data after the last dose.
  • Second, the mRNA in the vaccine breaks down pretty quickly because our cells need a way to stop mRNA from making too many proteins or too much protein.
  • But, even if for some reason our cells did not break down the vaccine mRNA, the mRNA stops making the protein within about a week, regardless of the body’s immune response to the protein.

Both vaccines can induce strong reactions, especially after the second shot, including headaches, muscle and joint pain, and fever. For example, in the Moderna trial, after the second dose of the shot, most people under 65 experienced fatigue and muscle pain; about half had chills, and 1 in 6 people got a fever. With both vaccines, these side effects are less common in older adults.

Concerns: Gene Therapy, Alteration of DNA.

 

 

2)    Viral vector vaccines (Low Risk)

A viral vector vaccine is a vaccine that uses a viral vector to deliver genetic material coding for a desired antigen into the recipient's host cells. Viral vector vaccines use a modified version of a different virus (the vector) to deliver important instructions to our cells. An adenovirus vaccine is a virus that has been altered so that it can't make you sick, it can't replicate, it cannot integrate into your DNA, so they take out some really important parts of that virus genome. What's done to the virus is that actually a little genetic snippet is exchanged and placed into the adenovirus that is actually from the COVID virus.

Viral vector vaccines do not cause infection with either the virus used as the vector, or the source of the antigen. The genetic material it delivers does not integrate into a person's genome.[1]

Viral vector vaccines enable antigen expression within cells and induce a robust cytotoxic T cell response, unlike subunit vaccines which only confer humoral immunity. Most viral vectors are designed to be incapable of replication because the necessary genes are removed.

 

 

Brand Name

Country of Origin

Effectiveness/ Side effects

Sputnik Light

Sputnik Layt or Lajt. First dose of Sputnik V

Russia

 

Sputnik V

Gam-KOVID-Vak

Russia

 

Oxford–AstraZeneca

Covishield, Vaxzevria

British-Sweden

Rare Blood clotting

Convidecia

 

China

 

Johnson & Johnson

Janssen

America and Neither land

 

Grad-COV2

 

Italy

Underdevelopment

 

  1. First, the vector (not the virus that causes COVID-19, but a different, harmless virus) will enter a cell in our body and then use the cell’s machinery to produce a harmless piece of the virus that causes COVID-19. This piece is known as a spike protein and it is only found on the surface of the virus that causes COVID-19.
  2. Next, the cell displays the spike protein on its surface, and our immune system recognizes it doesn’t belong there. This triggers our immune system to begin producing antibodies and activating other immune cells to fight off what it thinks is an infection.
  3. At the end of the process, our bodies have learned how to protect us against future infection with the virus that causes COVID-19. The benefit is that we get this protection from a vaccine, without ever having to risk the serious consequences of getting sick with COVID-19. Any temporary discomfort experienced after getting the vaccine is a natural part of the process and an indication that the vaccine is working.

 

3)    Conventional inactivated vaccines

An inactivated vaccine (or killed vaccine) is a vaccine consisting of virus particles, bacteria, or other pathogens that have been grown in culture and then killed to destroy disease producing capacity. In contrast, live vaccines use pathogens that are still alive (but are almost always attenuated, that is, weakened). Pathogens for inactivated vaccines are grown under controlled conditions and are killed as a means to reduce infectivity and thus prevent infection from the vaccine. The virus is killed using a method such as heat or formaldehyde.

Inactivated vaccines are not strongly influenced by antibodies in the host body, compared to live vaccines. This means that they can be administered when antibodies are present in the blood, such as during infancy or after being given medication containing antibodies.

Inactivated vaccines cannot replicate and always require repeated doses for immunity to be achieved. The first dose is the one that prepares the immune system to respond, but a protective immune response does not develop until the second or later doses.

 

Brand Name

Country of Origin

Effectiveness

BBIBP-CorV

Sinopharm

Beijing, China

 

Chinese Academy of Medical Sciences

 

China

 

CoronaVac

Sinovac

Sinovac Biotech, China

Low efficiency against Delta Variant

Covaxin

BBV152

Bharat Biotech, India

Phase 3 Trial results awaited.

CoviVac

КовиВак

Chumakov Centre, Russia

 

COVIran Barakat

 

Shifia, Iran

Very low participants for trials

Minhai-Kangtai

 

China

 

QazVac

 

Kazakastan

Even Phase I trials not published

WIBP-CorV

 

China

 

Valneva

 

France

 

 

 

 

4)     Protein subunit vaccines

 

Brand Name

Country of Origin

Effectiveness

EpiVacCorona

EpiVakKorona

Russia

Low Antibodies

RBD-Dimer

ZIFIVAX

China

 

Novavax

 COV2373,

Covovax

America

Underdevelopment

KBP

 

America

Underdevelopment

VAT00002 and VAT00008

Vaccino

Sanofi Pasteur and GSK

France and England

Low immune response in people above 50. Underdevelopment

ARCT021

 

Singapore

Underdevelopment

Abdala

 

Cuba

Underdevelopment

Nanocovax

 

Vietnam

 

SCB 2019

 

China

 

 

Rather than injecting a whole pathogen to trigger an immune response, subunit vaccines (sometimes called acellular vaccines or recombinant, conjugate, and polysaccharide vaccines) contain purified pieces of it, which have been specially selected for their ability to stimulate immune cells. Because these fragments are incapable of causing disease, subunit vaccines are considered very safe. Just like inactivated vaccines, the vaccine is completely "dead", and is therefore less risky.

Other Than above types

5)    Attenuated Vaccines

The key difference between live attenuated and inactivated vaccines is that live attenuated vaccines are vaccines that contain pathogens that have been weakened or attenuated, while inactivated vaccines are vaccines that contain pathogens that have been killed or have been altered.

Live attenuated vaccines are vaccines that contain pathogens (bacteria, viruses) that have been weakened (attenuated). An attenuated vaccine is created by reducing the virulence of a pathogen. But in an attenuated vaccine, the pathogen is still viable. In the process of attenuation, infectious agents are altered to make them less virulent. These vaccines are different from inactivated vaccines that are produced by killing the pathogen. Attenuated vaccines trigger a strong immune response that is long-lasting. Moreover, attenuated vaccines produce a stronger and more durable immune response with a quick immunity onset. The function of an attenuated vaccine is to encourage the body to create antibodies and memory cells in response to a specific pathogen such as bacteria and viruses.

Bacillus Calmette-Guerin (BCG) vaccine underdevelopment with Australia.

6)    Virus Like Particle (VLP)

Under development with Serum institute.

 

7)    Multitope peptide based vaccines.

COVAXX UB-612 (America).

 

8)    DNA Vaccines (Long Term Risky Route)

INO 4800, AG 030, NVoc, GX-19N, ZycovD (India, Cadilla Healthcare)

  

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