Epidemic waves occur due to a combination of factors:
Pathogen Evolution: Pathogens can mutate, leading to new variants that may evade immunity or be more transmissible. Population Immunity: Initially, a large number of individuals are susceptible. Over time, immunity builds up through infection or vaccination, reducing transmission. Behavioral Changes: Human activities such as social distancing, mask-wearing, and mobility changes can influence the spread of the disease. Seasonality: Some viruses, like influenza, exhibit seasonal patterns affecting their transmission dynamics.
