Vaccination during a pandemic - a public health challenge

Abstract

Since the emergence of COVID 19 virus, scientists all over the world are working at breakneck speed to develop a vaccine. Development of a vaccine is not a competitive race to the finish as it must pass through a stringent process of evaluation. The process includes vaccines’ immunogenicity, duration of immunity, efficacy of protection, interaction with other antigens, dosage, route of administration, packaging, and thermostability and expected adverse events and safety. Efficacy of a new vaccine is measured in clinical trials under ideal conditions, whereas its effectiveness is measured in the field under actual program conditions. (1) In normal circumstances, vaccine development is a prolonged process, averaging over 10 years from start to finish (2). To meet the urgent, need a COVID 19 vaccine may be available in a much shorter-term frame, at the earliest in 18 months.