Panera-Martínez Sarah, Capita Rosa, García-Fernández Camino, Alonso-Calleja Carlos
Department of Food Hygiene and Technology, Veterinary Faculty, University of León, 24071 León, Spain.
Institute of Food Science and Technology, University of León, 24071 León, Spain.
Microorganisms. 2023 Sep 4;11(9):2232. doi: 10.3390/microorganisms11092232.
The prevalence of in 30 samples of poultry was determined using culture-dependent (isolation on OCLA and confirmation by conventional polymerase chain reaction -PCR-, OCLA&PCR) and culture-independent (real-time polymerase chain reaction, q-PCR) methods. was detected in 15 samples (50.0%) by OCLA&PCR and in 20 (66.7%) by q-PCR. The concentrations (log cfu/g) of (q-PCR) ranged from 2.40 to 5.22 (total cells) and from <2.15 to 3.93 (viable cells). The two methods, q-PCR using a viability marker (v-PCR) and OCLA&PCR (gold standard), were compared for their capacity to detect viable cells of , with the potential to cause human disease. The values for sensitivity, specificity and efficiency of the v-PCR were 100%, 66.7% and 83.3%, respectively. The agreement between the two methods (kappa coefficient) was 0.67. The presence of nine virulence genes (, , , , , , , and ) was studied in 45 isolates (three from each positive sample) using PCR. All the strains harbored between six and nine virulence genes. Fifteen isolates (33.3% of the total) did not show the potential to form biofilm on a polystyrene surface, as determined by a crystal violet assay. The remaining strains were classified as weak (23 isolates, 51.1% of the total), moderate (one isolate, 2.2%) or strong (six isolates, 13.3%) biofilm producers. The strains were tested for susceptibility to a panel of 15 antibiotics. An average of 5.11 ± 1.30 resistances per isolate was observed. When the values for resistance and for reduced susceptibility were taken jointly, this figure rose to 6.91 ± 1.59. There was a prevalence of resistance or reduced susceptibility of more than 50.0% for oxacillin, cefoxitin, cefotaxime, cefepime ciprofloxacin, enrofloxacin and nitrofurantoin. For the remaining antibiotics tested, the corresponding values ranged from 0.0% for chloramphenicol to 48.9% for rifampicin. The high prevalence and level of with numerous virulence factors in poultry underline how crucial it is to follow correct hygiene procedures during the processing of this foodstuff in order to reduce the risk of human listeriosis.
采用依赖培养的方法（在OCLA上分离并通过常规聚合酶链反应-PCR-进行确认，即OCLA&PCR）和不依赖培养的方法（实时聚合酶链反应，q-PCR）测定了30份家禽样本中[具体病原体名称未给出]的流行情况。通过OCLA&PCR在15份样本（50.0%）中检测到了[具体病原体名称未给出]，通过q-PCR在20份样本（66.7%）中检测到了[具体病原体名称未给出]。[具体病原体名称未给出]（q-PCR）的浓度（log cfu/g）范围为2.40至5.22（总细胞）以及<2.15至3.93（活细胞）。比较了两种方法，即使用活力标记的q-PCR（v-PCR）和OCLA&PCR（金标准）检测[具体病原体名称未给出]活细胞的能力，该病原体有可能导致人类疾病。v-PCR的敏感性、特异性和效率值分别为100%、66.7%和83.3%。两种方法之间的一致性（kappa系数）为0.67。使用PCR研究了45株[具体病原体名称未给出]分离株（每个阳性样本3株）中9种毒力基因（[具体基因名称未给出]）的存在情况。所有菌株携带6至9种毒力基因。通过结晶紫试验确定，15株分离株（占总数的33.3%）没有在聚苯乙烯表面形成生物膜的潜力。其余菌株被分类为弱生物膜产生菌（23株，占总数的51.1%）、中度生物膜产生菌（1株，占2.2%）或强生物膜产生菌（6株，占13.3%）。测试了这些菌株对一组15种抗生素的敏感性。观察到每株分离株平均有5.11±1.30种耐药性。当将耐药性和敏感性降低的值合并计算时，这个数字上升到6.91±1.59。对苯唑西林、头孢西丁、头孢噻肟、头孢吡肟、环丙沙星、恩诺沙星和呋喃妥因的耐药性或敏感性降低的流行率超过50.0%。对于其余测试的抗生素，相应的值范围从氯霉素的0.0%到利福平的48.9%。家禽中[具体病原体名称未给出]的高流行率和大量毒力因子表明，在这种食品加工过程中遵循正确的卫生程序以降低人类李斯特菌病风险是多么关键。
