Zhang Shanshan, Sun Xiaoxi, Chang Wenjiao, Dai Yuanyuan, Ma Xiaoling
School of Medicine, Shandong University, Ji'nan, 250061, PR China.
Department of Clinical Laboratory, Affiliated Provincial Hospital of Anhui Medical University, Hefei, 230001, PR China.
PLoS One. 2015 Aug 19;10(8):e0136082. doi: 10.1371/journal.pone.0136082. eCollection 2015.
Vancomycin-intermediate Staphylococcus aureus (VISA) and heterogeneous VISA (hVISA) are associated with vancomycin treatment failure, and are becoming an increasing public health problem. Therefore, we undertook this study of 91 published studies and made subgroup comparisons of hVISA/VISA incidence in different study years, locations, and types of clinical samples. We also analyzed the genetic backgrounds of these strains.
A systematic literature review of relevant articles published in PubMed and EMBASE from January 1997 to August 2014 was conducted. We selected and assessed journal articles reporting the prevalence rates of hVISA/VISA.
The pooled prevalence of hVISA was 6.05% in 99,042 methicillin-resistant S. aureus (MRSA) strains and that of VISA was 3.01% in 68,792 MRSA strains. The prevalence of hVISA was 4.68% before 2006, 5.38% in 2006-2009, and 7.01% in 2010-2014. VISA prevalence was 2.05%, 2.63%, and 7.93%, respectively. In a subgroup analysis of different isolation locations, the prevalence of hVISA strains was 6.81% in Asia and 5.60% in Europe/America, and that of VISA was 3.42% and 2.75%, respectively. The frequencies of hVISA isolated from blood culture samples and from all clinical samples were 9.81% and 4.68%, respectively, and those of VISA were 2.00% and 3.07%, respectively. The most prevalent genotype was staphylococcal cassette chromosome mec (SCCmec) II, which accounted for 48.16% and 37.74% of hVISA and VISA, respectively. Sequence Type (ST) 239 was most prevalent.
The prevalence of hVISA/VISA has been increasing in recent years, but has been grossly underestimated. Its incidence is higher in Asia than in Europe/America. hVISA is isolated from blood culture samples more often than from other samples. These strains are highly prevalent in epidemic MRSA strains. This study clarifies the epidemiology of hVISA/VISA and indicates that the detection of these strains and the control of nosocomial infections must be strengthened.
万古霉素中介金黄色葡萄球菌（VISA）和异质性VISA（hVISA）与万古霉素治疗失败相关，正日益成为一个公共卫生问题。因此，我们对91项已发表的研究进行了此项研究，并对不同研究年份、地点及临床样本类型中的hVISA/VISA发病率进行了亚组比较。我们还分析了这些菌株的基因背景。
对1997年1月至2014年8月在PubMed和EMBASE上发表的相关文章进行系统的文献综述。我们筛选并评估了报告hVISA/VISA患病率的期刊文章。
在99,042株耐甲氧西林金黄色葡萄球菌（MRSA）中，hVISA的合并患病率为6.05%，在68,792株MRSA中VISA的合并患病率为3.01%。2006年前hVISA的患病率为4.68%，2006 - 2009年为5.38%，2010 - 2014年为7.01%。VISA的患病率分别为2.05%、2.63%和7.93%。在不同分离地点的亚组分析中，亚洲hVISA菌株的患病率为6.81%，欧美为5.60%，VISA的患病率分别为3.42%和2.75%。从血培养样本和所有临床样本中分离出的hVISA频率分别为9.81%和4.68%，VISA的频率分别为2.00%和3.07%。最常见的基因型是葡萄球菌盒式染色体mec（SCCmec）II型，分别占hVISA和VISA的48.16%和37.74%。序列型（ST）239最为常见。
近年来hVISA/VISA的患病率一直在上升，但一直被严重低估。其在亚洲的发病率高于欧美。从血培养样本中分离出hVISA的频率高于其他样本。这些菌株在流行的MRSA菌株中高度流行。本研究阐明了hVISA/VISA的流行病学情况，并表明必须加强对这些菌株的检测及医院感染的控制。
