On 2020-03-01 a superspreading event most likely occurred in United Kingdom. 18 days later (2020-03-19) it started to super-spread through the community. A total of 290 copies of this genome (that represents the core of the outbreak), were reported in Gisaid, a proxy for primary transmissions, along with 1289 genomes that are one-step mutation with respect to the core genome (a proxy for secondary transmissions). The signature for the likely superspreading event ends at about 2020-04-18, 47 days after it started, with 22344 sequences found in total.
The last sequence of the superspreading event was collected on 2020-06-17.