COVID-19, short for coronavirus disease 2019, is a contagious illness caused by the virus SARS-CoV-2. It emerged at the end of 2019 and quickly spread worldwide, leading to a global pandemic. The disease primarily affects the respiratory system but can impact other parts of the body as well. Symptoms range from none or mild, such as fever, cough, fatigue, loss of taste or smell, to severe respiratory distress. The virus spreads mainly through respiratory droplets and aerosols when an infected person breathes, talks, coughs, or sneezes. COVID-19 can lead to severe complications, especially in older adults and people with underlying health conditions, and some people suffer from long-term effects after infection (long COVID). Preventive measures include vaccination, mask-wearing, good hygiene, and physical distancing.
