The Great Plague - 1720, Cholera
Outbreak - 1820, The
Spanish Flu - 1920, Covid-19 - 2020 all acure 100 years apart. Hence Centur (coming from the term Century or 100 years), Ain (coming from Taint or to infect) and Demic (Meaning to pertain to people or populations) or Centuraindemic. (Sen-ture-ane-demic)