Covid vaccine emergency use approval: What are the principles in India? Why are 3 vaccines going through hurdle

Pune-based Serum Institute of India is conducting late-stage medical trials of Oxford-AstraZeneca's AZD1222 vaccine beneath the title of Covishield. (Reuters picture)Coronavirus Covid-19 vaccine in India: As crores of Indians are ready for a dose of Covid-19 vaccine, Serum Institute of India, Pfizer-BioNTech, and Bharat Biotech have submitted purposes for emergency use authorization (EUA)
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