Ecological method to control methicillin resistant Staphylococcus aureus

耐甲氧西林金黄色葡萄球菌(MRSA)作为医院感染的病原菌，在过去的20年里一直是一个臭名昭著的病原体，控制医院内的病原菌是当今世界面临的一个紧迫问题。本研究旨在寻找一种不依赖于抗微生物化疗而依赖于利用环境生物的生态学方法来控制耐甲氧西林金黄色葡萄球菌的方法，并培养具有感染控制能力的护理专业人员。对在医院工作的护士进行的鼻前庭检查显示，约40%的护士携带金黄色葡萄球菌，约25%的携带者携带MRSA。每2个月检查3次，明确有恒定携带者、恒定非携带者和间歇性携带者，采集环境微生物，检测每种微生物对MRSA的抑制作用。一些微生物抑制MRSA在琼脂平板和肉汤混合培养中的生长。1株I-1对MRSA的生长有明显的抑制作用。在去除毛发的小鼠皮肤上检测了其抑制活性。接种后10~14天，皮肤被MRSA定植，而GPR I-1菌株在几天内消失。在两组小鼠中，一组接种MRSA，另一组接种MRSA和I-1，MRSA在小鼠体内的定植时间基本相同。GPR I-1菌株在培养上清液中产生MRSA抑制物。将该抑制剂浓缩后涂抹在小鼠皮肤上，接种MRSA。但未发现抑制作用。综上所述，我们在体外发现了许多环境革兰氏阳性杆菌对MRSA的生长有抑制作用。然而，它在动物皮肤表面不起作用。为了研究它是否可以作为抗微生物药物使用，需要对其进行提纯。

Methicillin resistant Staphylococcus aureus (MRSA) as a causative agent of nosocomial infection has been notorious in the past 2 decades, and now control the pathogen in the hospital is a pressing problem in the world. The present study was planned to find a method to control MRSA not depending on anti-microbial chemotherapy but depend on an ecological method using some environmental organisms, and also the study was aimed at cultivating nurse specialists for infection control. Examinations of nasal vestibulum for the nurses working at the hospital revealed that about 40% of the nurses carried S. aureus and about 25% of the carriers had MRSA. In three times examinations every 2 months, it was clarified that there were constant carriers, constant non-carriers, and intermittent carriers.Environmental organisms were collected and each organisms was examined for the inhibition of MRSA. Some organisms inhibited the growth of MRSA on an agar plate and in mixed culture in broth. One strain i-1 markedly inhibited the growth of MRSA. The inhibitory activity was examined on the mouse skin from which the hair was removed. The skin was colonized by MRSA for 10 to 14 days after inoculation but GPR strain i-1 disappeared within a few days. In 2 groups of mice, one inoculated MRSA, another inoculated MRSA and i-1, the period of colonization by MRSA was almost the same. GPR i-1 strain produced MRSA inhibitor in the culture supernatant. The inhibitor was concentrated, applied on the mouse skin, and the MRSA was inoculated. However, no inhibitory effect was found. In conclusion, we found many strains of environmental Gram positive rods which inhibited the growth of MRSA in vitro. However, it was not active on the animal skin surface. The inhibitor should be purified to investigate whether it can be used as anti-microbial drug or not.