Effect of 2 Inactivated SARS-CoV-2 Vaccines on Symptomatic COVID-19 Infection in Adults

Abstract

Effective vaccines against COVID-19 are urgently needed to control the global pandemic. More than 280 candidate vaccines are in development worldwide, 23 of which are already in phase 3 trials using different platforms.¹ Among the platforms, inactivated vaccines have been extensively studied. They are generally safe and are widely used for prevention of respiratory infections, such as influenza, as well as other infectious diseases, such as hepatitis A, polio, and rabies.² The inactivated vaccines also have the advantage of being easily stored and shipped at 2 °C to 8 °C for years, making them suitable for many low-income countries and places with limited cold-storage capacity.