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Network based on epidemiological data. 14 apparently unrelated epi-clusters were identified, with 163 cases (circles) and 149 transmission links (arrows). Epi-clusters are numbered (number located on the index case) and circles’ diameter is proportional to the number of secondary cases. Color of the circles represent date of symptoms' onset: recorded (black circles) or not (grey circles). Arrows represent the transmission chain, from the infector to the infected.
