背景:乌干达的几种诊断环境缺乏实时性,强大的高通量技术,可对微生物进行全面分型,这是传染病监测的一个挫折。这项研究结合了各种湿式实验室诊断,以了解从乌干达动物中分离出的致病性葡萄球菌的流行病学以及对全球卫生安全优先事项的影响。
方法:采用中央诊断实验室(CDL)存档的记录和致病性葡萄球菌(来自动物)进行回顾性研究,马凯雷雷大学,乌干达,2012年1月至2019年12月。通过基质辅助激光解吸/电离飞行时间质谱(MALDI-TOFMS)鉴定细菌,并测试毒力因子[β内酰胺酶,卵磷脂酶,脱氧核糖核酸酶,溶血素]和对临床和兽医相关的十种抗菌药物的耐药性。还测试了四环素和甲氧西林抗性基因。
结果:流行的疾病是牛的乳腺炎和狗的皮肤感染。在MALDI-TOFMS检测的111种葡萄球菌中,79(71.2%)为金黄色葡萄球菌,假中间葡萄球菌27例(24.3%),Schleiferi葡萄球菌5例(4.5%)。所有这些菌株都表达溶血素。卵磷脂酶菌株的流行,青霉素酶,头孢菌素酶和DNA酶为35.9%(14/39),89.7%(35/39),0.0%(0/39)和87.2%(34/39),分别。葡萄球菌主要对早期青霉素(超过80%)耐药,四环素(57.7%),和氯霉素(46.2%)。氯唑西林的耐药性最低(0.0%),环丙沙星(9.6%),和头孢西丁(3.8%)。普通葡萄球菌的多药耐药(MDR)患病率为78.8%,金黄色葡萄球菌为82.2%,假中介的73.1%,和60.0%的S.schleiferi。牛分离株中的多药耐药葡萄球菌明显高于狗分离株(P<0.05)。通过对头孢西丁和mecA携带的耐药性测试,耐甲氧西林葡萄球菌(MRS)的患病率为3.8%。这四个菌株都是从狗皮肤感染中分离的。tetK基因是最主要的(35.4%),其次是tetM(25.0%)。
结论:在资源受限的设置中,综合诊断方法有望实现可持续的疾病监测和解决当前的能力差距。伴侣动物中MRS(人畜共患细菌)的出现可能会减少相关人类感染的治疗选择,对全球健康的威胁。
BACKGROUND: Several diagnostic environments in Uganda lack real-time, robust and high-throughput technologies for comprehensive typing of microbes, which is a setback to infectious disease surveillance. This study combined various wet laboratory diagnostics to understand the epidemiology of pathogenic staphylococci isolated from animals in Uganda and the implications for global health security priorities.
METHODS: A retrospective study was conducted employing records and pathogenic
staphylococci (from animals) archived at the Central Diagnostic Laboratory (CDL), Makerere University, Uganda, between January 2012 and December 2019. The bacteria were speciated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and tested for virulence factors [beta lactamases, lecithinase, deoxyribonuclease (DNase), haemolysins] and resistance to ten antimicrobials of clinical and veterinary relevance. Tetracycline and methicillin resistance genes were also tested.
RESULTS: The prevalent diseases were mastitis in cattle and skin infections in dogs. Of the 111
staphylococci tested by MALDI-TOF MS, 79 (71.2%) were Staphylococcus aureus, 27 (24.3%) were Staphylococcus pseudintermedius and 5 (4.5%) were Staphylococcus schleiferi. All these strains expressed haemolysins. The prevalence of strains with lecithinase, penicillinase, cephalosporinase and DNase was 35.9% (14/39), 89.7% (35/39), 0.0% (0/39) and 87.2% (34/39), respectively. Staphylococci were primarily resistant to early penicillins (over 80%), tetracycline (57.7%), and chloramphenicol (46.2%). Minimal resistance was noted with cloxacillin (0.0%), ciprofloxacin (9.6%), and cefoxitin (3.8%). The prevalence of multidrug resistance (MDR) was 78.8% for general
staphylococci, 82.2% for S. aureus, 73.1% for S. pseudintermedius, and 60.0% for S. schleiferi. Multidrug resistant
staphylococci were significantly more prevalent in the cattle isolates than in the dog isolates (P < 0.05). The prevalence of methicillin-resistant
staphylococci (MRS) tested by resistance to cefoxitin and mecA carriage was 3.8%. These four strains were all isolated from dog skin infections. The tetK gene was the most predominant (35.4%), followed by tetM (25.0%).
CONCLUSIONS: In resource-constrained settings, the approach of integrated diagnostics promises sustainable disease surveillance and the addressing of current capacity gaps. The emergence of MRS (zoonotic bacteria) in companion animals creates a likelihood of reduced treatment options for related human infections, a threat to global health.