influenza pandemic

An influenza pandemic occurs when a new flu virus emerges worldwide, for which most people have little or no immunity. This allows the virus to spread rapidly across countries and continents, causing widespread illness. Unlike seasonal flu outbreaks, which are predictable and usually less severe, a pandemic can result in a high number of infections, hospitalizations, and deaths, impacting healthcare systems and economies. Pandemics happen when a virus combines traits of animal, human, or other flu viruses, enabling it to infect humans easily and transmit efficiently from person to person.