COVID-19, caused by the novel coronavirus SARS-CoV-2, emerged in Wuhan, China, in late 2019 and quickly became a global pandemic. The disease primarily affects the respiratory system, causing symptoms ranging from mild (fever, cough, and fatigue) to severe (pneumonia, difficulty breathing, and organ failure). Older adults and individuals with underlying health conditions are at higher risk of severe illness.

COVID-19 spreads mainly through respiratory droplets when an infected person coughs, sneezes, or talks. It can also spread by touching surfaces contaminated with the virus and then touching the face. Governments worldwide implemented measures like lockdowns, social distancing, mask mandates, and vaccination campaigns to control the spread of the virus.

The development of vaccines by companies like Pfizer-BioNTech, Moderna, and AstraZeneca marked a significant step in controlling COVID-19. Vaccines have been shown to reduce the severity of symptoms and lower the risk of severe illness or death. However, the virus has continued to mutate, leading to new variants such as Delta and Omicron, which pose ongoing challenges in vaccine effectiveness and public health strategies.

Public health organizations, including the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC), continue to monitor the virus, adapt guidelines, and promote vaccination. While many countries have lifted strict restrictions, COVID-19 remains a health concern globally, highlighting the importance of continued vigilance, vaccination, and investment in healthcare infrastructure.