The world has experienced many pandemics, each one leaving behind serious human and economic consequences. When does a disease become a pandemic?

The Black Death was a plague that struck Europe and Asia in the mid-14th century. It was one of the most devastating pandemics humanity has ever experienced.

The Spanish flu pandemic of 1918 was one of the deadliest pandemics in history. It infected an estimated 500 million people worldwide (about a third of the population at the time) and killed 50 million. The 1918 flu pandemic was first detected in Europe, the United States, and parts of Asia before quickly spreading throughout the world. At the time, there was no vaccine or effective treatment for the disease.

We are experiencing days full of anxiety about the acute pneumonia caused by the new strain of coronavirus (Covid-19) when the number of infected people is constantly increasing, especially the epicenter in Wuhan city, China. The disease has spread to many countries around the world, people are afraid that this disease will become a new pandemic of humanity. In fact, we humans have experienced many major epidemics around the world, with very dangerous levels of destruction.