COVID-19, short for Coronavirus Disease 2019, is an infectious disease caused by the SARS-CoV-2 virus. The virus, which emerged in Wuhan, China, in December 2019, rapidly spread across the globe, leading the World Health Organization (WHO) to declare it a pandemic on March 11, 2020. While the WHO announced the end of the public health emergency in May 2023, the disease continues to circulate. COVID-19 primarily affects the respiratory system, with symptoms ranging from mild, such as fever, cough, sore throat, and loss of taste or smell, to severe, including shortness of breath and the potential for pneumonia.
The virus spreads through respiratory droplets and small particles produced when an infected person breathes, coughs, or sneezes. Transmission is more likely in close contact or in shared indoor spaces. Although most people recover fully, older adults, individuals with underlying health conditions (like cardiovascular disease, diabetes, or obesity), and those with weakened immune systems are at higher risk of developing severe illness. Globally, there have been over 780 million cases and more than 7.1 million deaths reported to the WHO since the start of the pandemic, though the actual numbers are believed to be higher due to underreporting and variations in testing practices. Vaccination remains a key preventative measure against COVID-19.
