Influenza pandemic occurs after 7 - 10 years. This kind of disease distributions in time is known as?

Secular trend

Cyclical trend

Seasonal trend

Short time fluctuation

The influenza pandemic occurs every 7 to 10 years and is known as a cyclic or periodic distribution

This cyclical pattern is characteristic of certain infectious diseases,

including influenza, which exhibits periodic outbreaks or epidemics on a global scale.