The COVID-19 pandemic (also known as the coronavirus pandemic), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began with an outbreak of COVID-19 in Wuhan, China, in December 2019. It spread to other areas of Asia, and then worldwide in early 2020. The World Health Organization (WHO) declared the outbreak a public health emergency of international concern (PHEIC) on 30 January 2020, and assessed the outbreak had become a pandemic on 11 March.
COVID-19 symptoms range from asymptomatic to deadly, but most commonly include fever, sore throat, nocturnal cough, and fatigue. Transmission of the virus is often through airborne particles. Mutations have produced many strains (variants) with varying degrees of infectivity and virulence. COVID-19 vaccines were developed rapidly and deployed to the general public beginning in December 2020, made available through government and international programs such as COVAX, aiming to provide vaccine equity. Treatments include novel antiviral drugs and symptom control. Common mitigation measures during the public health emergency included travel restrictions, lockdowns, business restrictions and closures, workplace hazard controls, mask mandates, quarantines, testing systems, and contact tracing of the infected.
The pandemic caused severe social and economic disruption around the world, including the largest global recession since the Great Depression.