Normally, the Classic period in Mesoamerica is characterized as the stage in which the arts, science, urbanism, architecture, and social organization reached their peak. This period was also dominated by the influence of Teotihuacan throughout the region, and the competition between the different Mesoamerican states led to continuous warfare.
The most common name for the killer virus, the Spanish flu, implied, of course, that it originated in Spain. Perhaps this was because there were serious outbreaks in both Madrid and Seville that infected eight million people in May of 1918 alone, even almost taking out the king himself, Alfonso XIII.
Flu is also known as Influenza. Influenza (aka flu) is a contagious respiratory viral illness that can cause mild to severe illness including death. There is treatment available to decrease symptoms, but it is better to prevent the flu is by getting the vaccine every year.