Rt tends to 1

Effective reproduction number at time (R_t) is the average number of secondary cases per one case at any given time. This number will vary as the outbreak progresses, and indicates real-time transmissibility. Effective control measures and behavioral changes, such as quarantine (檢疫隔離) enforcement, usage of face masks, travel restrictions, class suspensions, and social distancing, are all factors that may affect the R_t of a virus.

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R_t = 1

Each infected patient will go on to infect one other person. Statistically, this would mean that one new infected patient will replace another who had recovered or passed away from the disease. This also suggests that the outbreak is stabilizing, with no changes in number of infected people over time.