Takahashi Hideyuki, Haga Masae, Sunagawa Tomimasa, Saitoh Takehito, Kitahara Takeru, Matsumoto Sohkichi, Ohnishi Makoto
Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan.
Healthcare Center, Hokkaido University of Education, Hokkaido, Japan.
J Infect Chemother. 2016 Jul;22(7):501-4. doi: 10.1016/j.jiac.2015.12.016. Epub 2016 Feb 16.
The detailed epidemiology of meningococcal diseases in Japan has yet to be determined and, moreover, the healthy carriage rate is also unknown. In this study, to obtain insight into the carriage rate of Neisseria meningitidis in healthy individuals in Japan, we developed a new method to detect the N. meningitidis-specific ctrB gene, one of the genes encoding enzymes for capsule synthesis, by Loop-Mediated Isothermal Amplification (LAMP) and examined the meningococcal carriage rate by using self-collected oral throat wash specimens from 836 students at a university. Examination by LAMP showed that 7 out of 836 samples were positive for N. meningitidis DNA, and the results were also verified by the nested PCR method for the meningococcus specific ggt gene. The N. meningitidis carriage rate in healthy individuals was estimated to be 0.84%. Moreover, we further confirmed by the nested-PCR-based serogroup typing method that 5 of the positive samples belonged to serogroup Y, 1 belonged to group B and 1 was unidentifiable. Considering the epidemiology for meningococcal diseases in Japan, the carriage rate and the serogroup profile seem to be consistent with low incidence of meningococcal diseases and serogroup distribution of clinical meningococcal isolates in Japan, respectively.
日本脑膜炎球菌病的详细流行病学情况尚未确定，此外，健康人群的带菌率也不清楚。在本研究中，为了深入了解日本健康个体中脑膜炎奈瑟菌的带菌率，我们开发了一种新方法，通过环介导等温扩增（LAMP）检测脑膜炎奈瑟菌特异性ctrB基因（该基因是编码荚膜合成酶的基因之一），并使用从一所大学的836名学生自行采集的口腔咽漱液标本检测脑膜炎球菌的带菌率。LAMP检测显示，836份样本中有7份脑膜炎奈瑟菌DNA呈阳性，结果也通过针对脑膜炎球菌特异性ggt基因的巢式PCR方法得到验证。健康个体中脑膜炎奈瑟菌的带菌率估计为0.84%。此外，我们通过基于巢式PCR的血清群分型方法进一步确认，阳性样本中有5份属于血清群Y，1份属于B群，1份无法鉴定。考虑到日本脑膜炎球菌病的流行病学情况，带菌率和血清群分布似乎分别与日本脑膜炎球菌病的低发病率和临床脑膜炎球菌分离株的血清群分布一致。
