Pandemics are regarded as large-scale outbreaks of infectious disease that has the potential to significantly increase morbidity and mortality over a wide geographical area, which is accompanied by economic, social and political disruption. The likelihood of pandemic, especially caused by viral infectious diseases has increased over the past few years. The 21st century is just two decades old but it has already witnessed some of the deadliest viral pandemics having far-reaching consequences. These include Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) (2002), Influenza A virus subtype H1N1 (H1N1) (2009), Middle East Respiratory Syndrome Coronavirus (MERS-CoV) (2012) and Ebola virus (2013) and the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) (2019-present). The viruses may adopt various mechanisms to invade and hijack the cellular machinery of the host cell, followed by infection-mediated immunomodulation and progressive inflammation, which in turn, may affect the functioning of different organ systems of the body. Although effective commercial vaccines are unavailable for most of these viruses, those against SARS-CoV-2 are being developed at an unprecedented speed with few of the vaccines already being approved for commercial distribution. Significant policy attention is required to limit the outbreak of such pandemics and to expand and sustain investment to build preparedness and health capacity.