Mixing AstraZeneca with mRNA vaccines offers a ‘good protection’: Danish study

Denmark’s State Serum Institute on August 2, 2021, said that combining the AstraZeneca COVID-19 vaccine with the second dose of mRNA vaccines either Moderna or Pfizer-BioNTech’s vaccines offers a ‘good protection’.

Over 1,44,000 people of Denmark, including mostly frontline workers and the elderly, were administered with the first dose of AstraZeneca followed by a second dose of either Moderna or Pfizer-BioNTech vaccines.

The move to administer different COVID-19 vaccines became necessary in Denmark because the country discontinued vaccination with AstraZeneca over concerns of side effects. Many countries across the world are looking into administering different COVID-19 vaccines for second doses.

What did the study tell?

•The study showed that 14 days after completion of vaccination with different COVID-19 vaccines, the risk of infection was reduced by 88 per cent compared to unvaccinated individuals.

•The study noted a ‘high efficacy’ compared to the 90 per cent efficacy rate of two doses of Pfizer-BioNTech’s vaccine.

•The study was conducted over a span of 5 months from February to June 2021. It was published last week.

•The study however did not provide data on whether the combination of different COVID-19 vaccines as mentioned showed protection against the Delta variant, which is rampant in Denmark.

•The study did not report any deaths or hospitalizations due to COVID-19 after administering the combination of vaccines as mentioned.

What are mRNA COVID-19 vaccines?

•mRNA vaccines, known as messenger RNA vaccines, demonstrate the cells of the human body the process of producing the spoke protein to trigger an immune response inside our bodies so that in case of actual exposure to the COVID-19 virus, the body knows the immune response to fight against it.

•Both Moderna and Pfizer-BioNTech’s vaccines are mRNA vaccines.

Moderna’s mRNA COVID-19 vaccine: Efficacy

•Moderna’s vaccine has been found to be 94.1 per cent effective, beginning 14 days after the first dose. It has also been found effective against the Delta variant of COVID-19.

Pfizer-BioNTech’s mRNA COVID-19 vaccine: Efficacy

•Pfizer-BioNTech’s mRNA COVID-19 vaccine has been found to be 97 per cent effective after two doses.

Also read: Mixing COVID-19 vaccines – Possible Benefits and Concerns | Explainer of the Day

India: CDSCO granted approval for trials for mixing of COVAXIN and COVISHIELD

•Regarding the mixing of COVID-19 vaccines in India, on July 29, 2021, The Subject Expert Committee (SEC) of the Central Drugs Standard Control Organization (CDSCO) had granted permission to Christian Medical College in Vellore for conducting trials of mixing COVID-19 vaccines – COVAXIN and COVISHIELD.

Also read: COVID-19 Vaccines: CDSCO grants approval to mixing of COVAXIN and COVISHIELD