COVID Vaccines: Introduction, Covishield Details, Comparative Study of COVID-19 Vaccines and Other Vaccines in Pipeline

achaurasiya

5 years ago

COVID Vaccines

COVID vaccines give a sense from its name and following renowned companies are involved to develop-

Oxford Uni-AstraZenica
Moderna
Pfizer-BioNTech
Gamaleya

Covishield

Covishield vaccine is developed by the Oxford-AstraZeneca and is being manufactured locally by the Serum Institute of India, the world’s largest vaccine manufacturer that produces more than 50 million doses a month. This vaccine is made from a weakened version of a common cold virus, an adenovirus from chimpanzees.

Note: Please come wearing comfortable clothes as COVID-19 vaccine is given intramuscularly at the upper arm and thus he had to take off his tight clothes as shown above clip.

Route of administration: Intramuscular (deltoid region)

Doses: two

Volume: 0.5 ml

Pain: Just like an ordinary ant bite

Next dose: Within 4 to 6 weeks but not more than 12 weeks

Note: COVID vaccine can’t cause COVID-19 infection since SARS-CoV-2 particles are not used to prepare this vaccine but the Covishield is made of a common cold virus, adenovirus from chimpanzees.

Vaccine type: Latest generation (recombinant vector vaccine)

Age group: 18 years and above age group are allowed to take this vaccine.

Who are not eligible to take Covishield vaccine?

Age below 18 years
Pregnant and breast-feeding women
A person who has faced a severe side effect in any earlier vaccination.
Active COVID-19 infection
A person with acute severe illness or acute severe febrile illness
COVID-19 patients who have taken monoclonal antibodies or convalescent plasma therapy.
People having bleeding or coagulation disorders

Note: For the above points ( 4,5,6 and 7), the vaccine is only given in certain conditions.

Side effects of Covishield vaccine-

Common: affect up to 1 in 10 people

A lump at the injection site
Fever
Vomiting
Flu-like symptoms such as temperature, sore throat, running nose, cough and chills.

Uncommon side effects-

May affect up to 1 in 100 people

Dizzy
Decreased appetite
Abdominal pain
Enlarged lymph nodes
Excessive sweating
Itchy skin
rash

Effective rate

62-90%

The Mechanism of a Vaccine

In an ideal scenario, whenever a vaccine is first administered, it is phagocytized by an antigen-presenting cell.
Recent research suggests that it is particularly important that the vaccine be taken up by a dendritic cell.
This is because dendritic cells play a key role in activating T cells, which become helper T cells.
From there, the activated Th cells go on to activate mature B-cells.
These activated B-cells divide into two cell types, antibody-producing plasma cells and, most importantly, memory B cells.

Importance of Secondary Immune Response

During the secondary immune response, the body mounts a quicker, more robust attack on the pathogen.

Thus, the pathogen is cleared from the body before it has the chance to cause an infection.

Comparative Study of COVID-19 Vaccines

Comparative study of COVID-19 vaccines are given in a table –

Other Vaccines in Pipeline

The other COVID vaccines which are in different stages of trials in India to test safety and efficacy include-

ZyCov-Di (developer-Ahmedabad-based Zydus-Cadila)
In partnership with US-based Dynavax and Baylor College of Medicine, Hyderabad-based Biological E, the first Indian private vaccine company, is developing a vaccine.
In partnership with Seattle-based HDT Biotech Company, HGCO19, India’s first mRNA vaccine developed by Pune-based Genova, uses bits of genetic code to induce an immune response. A nasal vaccine (Bharat BioTech)
The Sputnik V vaccine (developers- Dr. Reddy’s Lab and Gamaleya National Centre in Russia)
A second vaccine being developed by Serum Institute of India and American vaccine development company Novavax