Zapka C, Leff J, Henley J, Tittl J, De Nardo E, Butler M, Griggs R, Fierer N, Edmonds-Wilson S
GOJO Industries, Inc., Akron, Ohio, USA
Department of Ecology & Evolutionary Biology, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA.
mBio. 2017 Mar 28;8(2):e00093-17. doi: 10.1128/mBio.00093-17.
Hands play a critical role in the transmission of microbiota on one's own body, between individuals, and on environmental surfaces. Effectively measuring the composition of the hand microbiome is important to hand hygiene science, which has implications for human health. Hand hygiene products are evaluated using standard culture-based methods, but standard test methods for culture-independent microbiome characterization are lacking. We sampled the hands of 50 participants using swab-based and glove-based methods prior to and following four hand hygiene treatments (using a nonantimicrobial hand wash, alcohol-based hand sanitizer [ABHS], a 70% ethanol solution, or tap water). We compared results among culture plate counts, 16S rRNA gene sequencing of DNA extracted directly from hands, and sequencing of DNA extracted from culture plates. Glove-based sampling yielded higher numbers of unique operational taxonomic units (OTUs) but had less diversity in bacterial community composition than swab-based sampling. We detected treatment-induced changes in diversity only by using swab-based samples ( < 0.001); we were unable to detect changes with glove-based samples. Bacterial cell counts significantly decreased with use of the ABHS ( < 0.05) and ethanol control ( < 0.05). Skin hydration at baseline correlated with bacterial abundances, bacterial community composition, pH, and redness across subjects. The importance of the method choice was substantial. These findings are important to ensure improvement of hand hygiene industry methods and for future hand microbiome studies. On the basis of our results and previously published studies, we propose recommendations for best practices in hand microbiome research. The hand microbiome is a critical area of research for diverse fields, such as public health and forensics. The suitability of culture-independent methods for assessing effects of hygiene products on microbiota has not been demonstrated. This is the first controlled laboratory clinical hand study to have compared traditional hand hygiene test methods with newer culture-independent characterization methods typically used by skin microbiologists. This study resulted in recommendations for hand hygiene product testing, development of methods, and future hand skin microbiome research. It also demonstrated the importance of inclusion of skin physiological metadata in skin microbiome research, which is atypical for skin microbiome studies.
手部在个体自身、个体之间以及环境表面的微生物群传播中起着关键作用。有效测量手部微生物组的组成对于手部卫生科学至关重要,这对人类健康具有重要意义。手部卫生产品采用基于标准培养的方法进行评估,但缺乏用于非培养微生物组特征分析的标准测试方法。我们在50名参与者进行四种手部卫生处理(使用非抗菌洗手液、酒精基洗手液[ABHS]、70%乙醇溶液或自来水)之前和之后,采用棉签法和手套法对手部进行采样。我们比较了培养平板计数、直接从手部提取的DNA的16S rRNA基因测序以及从培养平板提取的DNA测序的结果。基于手套的采样产生了更多数量的独特操作分类单元(OTU),但与基于棉签的采样相比,细菌群落组成的多样性较低。我们仅通过基于棉签的样本检测到了处理引起的多样性变化(<0.001);我们无法通过基于手套的样本检测到变化。使用ABHS(<0.05)和乙醇对照(<0.05)后细菌细胞计数显著下降。基线时的皮肤水合作用与受试者的细菌丰度、细菌群落组成、pH值和发红情况相关。方法选择的重要性很大。这些发现对于确保手部卫生行业方法的改进以及未来手部微生物组研究非常重要。根据我们的结果和先前发表的研究,我们对手部微生物组研究的最佳实践提出了建议。手部微生物组是公共卫生和法医学等多个领域的关键研究领域。尚未证明非培养方法评估卫生产品对微生物群影响的适用性。这是第一项将传统手部卫生测试方法与皮肤微生物学家通常使用的更新的非培养特征分析方法进行比较的对照实验室临床手部研究。这项研究对手部卫生产品测试、方法开发和未来手部皮肤微生物组研究提出了建议。它还证明了在皮肤微生物组研究中纳入皮肤生理元数据的重要性,这在皮肤微生物组研究中并不常见。