Supplemental Digital Content 1: Pulsed field gel electrophoresis (PFGE) profiles of Kingella kingae isolates PFGE patterns, obtained with the enzyme EagI, of K. kingae oropharyngeal isolates before (first sampling) and 15 days after (second sampling) antibioprophylaxis using rifampin. Lane 1 and 20 : Lambda ladder molecular weight marker (Biorad) Lane 2 to 6 : K. kingae oropharyngeal isolates before antibioprophylaxis in infants; STF-5A, 12A, 13A, 15A and 16A, respectively. Lane 7 to 14 : K. kingae oropharyngeal isolates after antibioprophylaxis in infants; STF-2B, 6B, 7B, 13B, 15B, 16B, 19B and 35B, respectively. White arrow showing the additional band in the profile of isolate STF-6B from infant STF-6 (PCR and culture negative at first sampling). Lane 15 : Staff member’s oropharyngeal isolate at second sampling (PCR and culture negative at first sampling). Lane 16 to 19: The last four strains are unrelated controls chosen among reference strains (see http://www.pasteur.fr/cgi-bin/genopole/PF8/mlstdbnet.pl?page=browse&file=kingellak_isolates.xml): type strain (ATCC 23330) belonging to ST1 (lane 16); and 3 strains (HAN-26314, ATCC 23332, N10-6318; lane 17 to 19, respectively) representative of the major ST complexes (STc) circulating in France (STc6, STc14, STc23 respectively).