Viral Pandemics in the Past Two Decades: An Overview

An epidemic that occurs worldwide, involving many countries and affecting a large population is called as a pandemic. The ongoing corona virus disease (COVID-19) pandemic has not only adversely affected the global healthcare infrastructure, but has significantly impacted world economy, socio-political and cultural environment. There are 219 different types of viruses, known at present to be able to infect human beings. This number is just a tip of the iceberg, with the possibility of a substantial pool of undiscovered human viruses and millions of other virus species (which affect plants and non-human animals) that can be potentially infectious to humans as well. Throughout human history there have been numerous pandemics and disease outbreaks that have not only led to huge loss of life, but also hindered economic growth and development. Therefore, in this review article we wanted to highlight major viral pandemics that have occurred in the last two decades, to understand factors contributing to their emergence, transmission and suggest ways to curb future outbreaks.