FIG 3.

Species-level nasal microbial community analysis reveals S. aureus DNA in all nostrils. Subjects with known SANC status, as determined by culture, self-collected fresh nasal swabs which were immediately processed for total DNA extraction followed by microbial DNA enrichment. Shotgun sequencing was performed for 7 “noncarrier” and 6 S. aureus carrier nostrils. (A) Reads mapping to S. aureus (SA) genomes (strains) were present in all nostrils regardless of culture-defined SANC status. (B) Acinetobacter spp.: S. aureus ratio for noncarrier versus S. aureus carrier nostrils. The arrow indicates a carrier who nearly cleared S. aureus 4 days later. (C and D) DNA abundance ratio of S. epidermidis (SE, panel C) and C. pseudodiphtheriticum (D) to S. aureus for the same groups. Error bars represent the mean ± the standard error of the mean (SEM). P values are indicated for each comparison (unpaired t tests).