FIG. 2.
Distribution of stx prevalence in commercial ground beef by region. The distribution of the regional prevalence of STEC in commercial ground beef samples from seven of the eight BIFSCo microbiological monitoring regions (n = 4,133) is based on PCR screening for the presence of stx1 and/or stx2. The BIFSCo regions are defined in the text. The mean (horizontal bars) and standard deviation (vertical bars) for each region are shown. Each point within a region represents a monthly prevalence value. Note that only some months are represented twice in each region. The prevalence in samples from regions 2 and 5 was less than that of regions 7 and 8 (P < 0.05). None of the other comparisons between regions was statistically significantly different (P > 0.05).