背景：
在农业和医疗保健环境中预防和治疗新出现的人畜共患猪链球菌感染主要依靠抗生素。然而，在包括泰国在内的许多流行国家中，继续使用抗生素有助于抗生素抗性猪链球菌的出现和普及。同时，需要了解细菌病原体的抗生素敏感性模式以克服抗菌素耐药性问题，泰国分离的猪链球菌菌株的抗生素敏感性信息仍然有限。本研究旨在评估泰国分离的猪链球菌菌株对不同抗生素类别的敏感性，以便深入了解泰国不同地区猪链球菌菌株抗生素抗性模式的分布。

结果：
该研究揭示了在泰国不同地区分离的262株猪链球菌菌株的抗菌素耐药性和多药耐药性。易感性测试表明该国对猪链球菌菌株的大环内酯类和四环素类具有广泛的耐药性。 β-内酰胺类抗生素药物（包括头孢噻肟和头孢噻呋），万古霉素，氯霉素以及氟苯尼考可能是治疗猪和人类猪链球菌感染最有效的治疗药物。从无症状猪中分离青霉素G，庆大霉素，恩诺沙星和诺氟沙星的猪链球菌中间易感性的高流行率可能是猪链球菌抗生素耐药性出现的前提。在从无症状猪中分离的猪链球菌菌株中也发现了抗性，表明它们可以作为抗生素抗性基因的储库。

结论：
据我们所知，这是第一份关于泰国猪和人类分离的大量猪链球菌菌株抗菌素耐药性的报告。它揭示了猪和人类猪链球菌菌株的多药耐药性。从这项研究中获得的信息提高了人们的认识，并鼓励在人类健康和农业部门使用适当的抗生素药物处方和使用的最佳做法。

BACKGROUND:
Prophylaxis and treatment of emerging zoonotic Streptococcus suis infection in agricultural and healthcare settings mainly rely on antibiotics. However, continued use of antibiotics contributing to emergence and widespread of antibiotic resistant S. suis becomes a significant challenge in many endemic countries, including Thailand. Meanwhile, the knowledge of antibiotic susceptibility patterns of bacterial pathogens is required for overcoming the antimicrobial resistance problem, the information of antibiotic susceptibility of S. suis strains isolated in Thailand remains limited. This study aims to assess the susceptibility of Thai-isolated S. suis strains to different antibiotic classes in order to gain an insight into the distribution of antibiotic-resistant patterns of S. suis strains in different regions of Thailand.

RESULTS:
This study revealed the antimicrobial resistance and multidrug resistance of 262 S. suis strains isolated in different regions of Thailand. Susceptibility testing indicated widespread resistance to macrolides and tetracyclines of S. suis strains in the country. Beta-lactam antibiotic drugs (including cefotaxime and ceftiofur), vancomycin, chloramphenicol, as well as florfenicol were potentially the most effective therapeutic drugs for the treatment of S. suis infection in both pigs and humans. High prevalence of intermediate susceptibility of S. suis isolated from asymptomatic pigs for penicillin G, gentamicin, enrofloxacin, and norfloxacin could be the premise of the emergence of S. suis antibiotic resistance. Resistance was also found in S. suis strains isolated from asymptomatic pigs indicating that they could act as reservoirs of antibiotic resistance genes.

CONCLUSIONS:
To the best of our knowledge, this is the first report on antimicrobial resistance of a large collection of S. suis strains isolated from pigs and humans in Thailand. It revealed the multidrug resistance of S. suis strains in pigs and humans. The information gained from this study raises an awareness and encourage best practices of appropriate antibiotic drug prescribing and use among human health and agriculture sectors.

https://www.ncbi.nlm.nih.gov/pubmed/30606175