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Covaxin Vs Covishield

Published on Apr 13, 2021 and last reviewed on May 06, 2022   -  5 min read


The Indian Central Government first granted emergency use approval to Covishield and then to Covaxin. Read this article to know about these coronavirus vaccines in detail.

Covaxin Vs Covishield

What Is COVID-19?

COVID-19 is a disease caused by a strain of Coronavirus, where "CO" stands for CORONA, "VI" stands for VIRUS, and "D" for DISEASE. SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a unique strain of Coronavirus that has not been identified in humans earlier. The COVID-19 was behind the respiratory illness disorder first discovered in Wuhan, Hubei province, China, in December 2019. Since then, cases have been identified in almost all countries worldwide, and WHO declared it a pandemic on 11th March 2020.

What Is COVID-19 Vaccine?

Vaccines against the SARS-CoV-2 virus are known to produce antibodies that reduce the severity of the disease, symptoms, and spread of COVID-19. They are designed to provide acquired immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19). Since COVID vaccines were developed at a record speed, misinformations about them circulated fast and prevailed for a longer duration. Based on the clinical trials, studies, and data, researchers strongly recommend every individual to get vaccinated.

Before the COVID‑19 pandemic, there was an established knowledge about coronaviruses' structure and function due to research on the other strains of Coronavirus causing the Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS). This quickened the development of various vaccines against COVID-19. The COVID-19 vaccines and WHO Emergency Use Listing (EUL) offer varying levels of protection against infection, mild disease, severe disease, hospitalization, and death. COVID-19 vaccines are generally very effective at preventing severe illness, hospitalization, and death from all current virus variants. They are less effective at protecting against infection and mild disease than earlier virus variants, but the symptoms are more likely to be mild after vaccination.

What Is Covaxin?

Covaxin is India's first homemade vaccine against COVID-19, which has shown high antibody response levels in a mid-stage trial. The vaccine’s efficacy against COVID-19 of any severity was 78 %, 14 or more days after the second dose. The efficacy of vaccines against severe disease is 93 %. Adults aged less than 60 years had a 79 % efficacy rate, while those aged 60 and up had a 68 % efficacy rate.

Bharat Biotech has produced this vaccine in collaboration with the ICMR (Indian Council of Medical Research) and the NIV (National Institute of Virology), Pune. Covaxin is an inactivated vaccine, meaning it contains killed SARS-CoV-2. This makes it safe to be injected to acquire immunity. The manufacturers used a sample of the Coronavirus, which was isolated by India's National Institute of Virology. When administered, our immune system starts producing antibodies against the dead or inactivated virus. In the event of a future infection with this virus, the body will already have the antibodies to fight off the Coronavirus. Covaxin is given in two doses, administered four weeks apart.

Covaxin is produced by chemically treating novel Coronavirus samples to prevent them from replicating. The double-dose vaccine presented a significantly more powerful neutralizing antibody response in Phase II than in Phase I due to the variation in the dosing regimens that changed to a 4-week apart injection program from a 2-week course. But it also noted that the Phase II trial, which had 380 participants, included a small number of people aged between 12 to 18 years and 55 to 65 years. Covaxin was given approval for emergency use in children aged 2 to 18 years. The clinical trials in children are ongoing and the vaccine’s efficacy and immune response generated were found to be similar to that of adults in the trials. More investigations are required to establish immunogenicity in children and older individuals. It also said that while the trial involved participants from over nine Indian states, the study group lacked ethnic and gender diversity.

Covaxin Efficacy:

The WHO’s Strategic Advisory Group of Experts onImmunization(SAGE) says that the vaccine’s efficacy against COVID-19 of any severity was 78 %, 14 or more days after the second dose. The efficacy of vaccines against severe disease is 93 %. Adults aged less than 60 years had a 79 % efficacy rate, while those aged 60 and up had a 68 % efficacy rate. In contrast, the Coronavirus vaccines from Moderna and Pfizer have promoted 94.1 % and 95 % efficacy respectively. Covaxin has been examined on monkeys and hamsters, and the results have revealed that it provides enough immunity against the virus.

Covaxin Dosage:

Covaxin is administered in two doses, and the second dose is injected at an interval of 4 to 6 weeks.

Side Effects of Covaxin:

Side effects are generally rare. Side effects in most vaccinated persons are mild malaise and fever. Rarely skin rashes, dizziness, swelling of the face and the throat, weakness, pain, increased heart rate, nausea and vomiting, difficulty in breathing, itching, and other allergic reactions can occur.


The confined version of the Oxford-AstraZeneca COVID-19 vaccine is called Covishield. Serum Institute of India, the world's biggest vaccine producer by volume, joined with the British-Swedish drugmaker to deliver 1 billion doses of its COVID-19 vaccine.

It uses the common cold virus from the chimpanzee. This weakened version encodes instructions for building proteins from the new Coronavirus to generate an immune response and prevent infection. Two doses of the vaccine, which were given in four weeks intervals, were initially believed to provide the best protection against COVID-19.

The scientists reported that the Oxford vaccine had an overall potency of 70 % but could be around 90 % effective when administered a half dose followed by a total dose a month later. According to the preliminary investigation, the vaccine seemed to be more than 80 % effective in preventing severe illness among older individuals. Therefore, Covishield is a highly effective vaccine over novel coronavirus.

Covishield Efficacy:

Covishield has withstood testing in four countries with a demographically different population, thus guaranteeing that it is safe to be used. According to the Serum Institute of India's data, Covishield has an overall effectiveness of 76 % against symptomatic COVID-19 after more than 14 days after the second dose and 81.3 % if the doses were separated by more than 12 weeks.. However, it is still weaker than the Coronavirus vaccines from Moderna and Pfizer.

Covishield Dosage:

This vaccine is also administered in two doses and the second dose at an interval of 12 to 16 weeks. Covisheild vaccine can be safely stored at temperatures between 2 and 8 degrees celsius.

Side Effects of Covishield:

Side effects are generally rare. Side effects in most vaccinated persons are very mild malaise, mild fever. Rarely the skin rashes and other allergic reactions occur. The side effects of the Covishield vaccine are tenderness, pain, joint pain or muscle ache, generally feeling unwell, warmth, fatigue, redness, chills, itching, headache, swelling, nausea or bruising where the injection is given, feeling dizzy, enlarged lymph nodes, decreased appetite, excessive sweating, itchy skin, a lump at the injection site, flu-like symptoms.


Both the COVID-19 vaccines have some similarities and differences.

Vaccination produces antibodies and helps reduce the severity of the disease, thus reducing the spread of COVID-19. Therefore, the general public should come forward to get vaccinated, use masks, maintain social distance, and save themselves from this COVID-19 pandemic.

Last reviewed at:
06 May 2022  -  5 min read




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