Background. The new Covid-19 variants' emergence and rapid global spread pose a daunting public health emergency. The Covid-19 virus continues mutating by the emergence of new variants with high transmissibility. This paper illustrates the timing and lifespan of COVID-19 variants in California from January 2021 to February 2022 to provide a window showing the time frames of active variants.
Methods: This study used publicly available data on COVID-19, including covid variants of daily cases from the California Department of Health. Data from January 1, 2021, to February 28, 2022, were retrieved.
Results: The findings showed that the distribution of the variants could be divided into two main phases: January 2021 to June 2021 and from mid-summer 2021 to February 2022 from December to March. The first phase has more variations, while Omicron and Delta dominate the second phase.
Conclusions: This research indicates that variants have different characteristics and life spans. Recent variants have mutated faster than other older precedents. The lag between variants' international initiation for the first variants was longer than Omicron and Delta.