Explore the recorded discovery and history of SARS-CoV-2, with source links and stated limits.
SARS-CoV-2 causes COVID-19. Illness can range from mild to severe. Symptoms may change with variants and can differ depending on vaccination status. This profile summarizes possible symptoms rather than predicting an individual's illness.
WHO was informed of a pneumonia cluster in Wuhan in December 2019. This is an outbreak report, not proof of the first infection or biological origin.
WHO declared the outbreak a public health emergency of international concern on 30 January 2020.
WHO characterized COVID-19 as a pandemic on 11 March 2020.
The earliest reported cluster is not a confirmed first-ever infection. These sources do not establish a patient zero or the virus’s biological origin.
Source check: 2026-09-19. Educational content; independent scientific review remains pending.