ABSTRACT
Three cases of Bacillus cereus infection or colonization occurred in the same region in France, and milk from the milk bank was suspected as a possible common source of contamination. All Batches delivered to the three cases complied with the requirements of the bacteriological reference method recommended by good practices guidelines. Still, a retrospective analysis with a more sensitive method showed one batch to contain B. cereus, however straincomparison revealed no epidemiological link betweenisolates from patients and those from the milk. Consequently, in accordance with the precautionary principle, we developed a new sensitive method for the screening of pasteurized milk for pathogenic bacteria. From January 1 to August 31, 2017, 2526 samples of pasteurized milk were prospectively included in the study. We showed that a 20 mL sample of pasteurized milk incubated for 18 h at 37 °C under aerobic conditions was favoring the detection of B. Cereus. The nonconformity rate was 6.3% for the reference method and 12.6% for the improved method (p < 0.0001). Nonconformity was due to the presence of B. cereus in 88.5% of cases for the improved method and 53% of cases for the reference method (p < 0.0001). Thus our new method is improves the microbiological safety of the product distributed and only moderately increases the rate of bacteriological nonconformity .
Subject(s)
Bacillus cereus/isolation & purification , Food Contamination/prevention & control , Food Safety/methods , Milk Banks , Milk, Human/microbiology , Food Contamination/analysis , France , Humans , Pasteurization , Retrospective StudiesABSTRACT
This study describes the clinical and microbiological features associated with group B Streptococcus (GBS) bone and joint infections (BJIs). It was a retrospective analysis of adult cases of GBS BJIs reported to the French National Reference Center for Streptococci from January 2004 to December 2014. Clinical data and GBS molecular characteristics are reported. Strains were collected from 163 patients. The most frequent comorbidities were: solid organ cancer (n = 21, 21%) and diabetes mellitus (n = 20, 20%). The main infection sites were knee (47/155 = 30%) and hip (43/155 = 27%), and occurred on orthopedic devices in 71/148 cases (48%). CPS III (n = 47, 29%), Ia (n = 26, 16%) and V (n = 40, 25%) were predominant. Resistance to erythromycin, clindamycin and tetracycline was detected in 55/163 (34%), 35/163 (21%) and 132/163 (81%) strains, respectively. The most frequent sequence types were ST-1 (n = 21, 25%), ST-17 (n = 17, 20%) and ST-23 (n = 11, 13%). The rate of resistance to erythromycin was 0% for ST-17 strains, 52% (n = 11) for ST-1 and 44% (n = 7) for ST-23 (p < 0.001). GBS bone and joint infections predominantly occur in patients aged >50 years and/or with comorbidities such as cancer and diabetes mellitus. CPS type distribution and MLST are very similar to that of other adult GBS invasive infections.
