COVID-19 overview and impact of the SARS-CoV-2 virus

COVID-19 is a contagious disease caused by the SARS-CoV-2 coronavirus, which led to a global pandemic starting in January 2020. Symptoms vary and can include fever, fatigue, cough, breathing difficulties, and loss of taste or smell. While approximately one-third of infected individuals do not show noticeable symptoms, others may experience mild to moderate illness, severe respiratory issues, or critical conditions such as respiratory failure and organ dysfunction.

Transmission occurs through infectious particles inhaled via the air or through contact with contaminated surfaces and mucous membranes. Individuals can remain contagious for up to 20 days. Long-term complications, known as long COVID, can persist for months or years, and ongoing studies continue to investigate these lasting effects.