| Neisseria meningitidis (Nm), Haemophilus influenzae (Hi) and Streptococcus pneumoniae(Sp) are three main conditional pathogenic bacterium,which can be effectively prevented by using vaccine. Health carrier is an important source for the spread of the diseases. Investigating the carriage rate of these three pathogens among healthy people is very valuable to the diseases’prevention and control.For the low rate of the traditional bacterial culture, this research used Real-time PCR method to investigate these three bacteria carriage rates among healthy people, and compared the results with traditional method. The result may provide new idea and method for investigating bacteria carriage rate among healthy people.Two cross-sectional surveys were carried out in this study. On the first time, the study pointed at Nm, the total positive rate of Nm isolation was3.12%.,and at the same time the total positive rate of gene ctrA through Real-time PCR was7.97%. Compared with the bacterial culture, Real-time PCR increased detection rate significantly,the coincidence rate of these two methods was93.41%.Real-time PCR operated simply and was easy to apply. The second survey aimed at Hi, and the quality control of sample collecting, processing and testing were stricter higher than the first survey. Hi strains were isolated and gene ctrA,hpd,lytA were detection by Real-time PCR at one time. Comparing the two results, Real-time PCR testing positive rate was significantly increased after the improvement of quality control during the operation. So it indicated that Real-time PCR was a stable technique, with the grass roots promote which could improve the detection rate in the short term and could be spread to grass roots. In this study the Hi strains isolation rate was38.27%, and the positive rate of gene hpd was69.14%, the positive rate of gene ctrA was18.52%, and the positive rate of gene lytA was56.17%, which were detected by Real-time PCR. Compared with culture, Real-time PCR increased detection rate significantly again. It can be concluded again that Real-time PCR has high valent of use for pathogen carriage detection among health people. Real-time PCR has the following merits, easy to operate in low sampling environmental requirements, short experiment circles, few influenced by human factors, highly automation, easy pollution control, simultaneously multi pathogen-specific genes detecting ability,and so on. It indicated that Real-time PCR is an effective and accurate method to investigate conditional pathogenic bacteria carriage rate among healthy population, it’s also a helpful supplement to traditional bacteria culture. These two methods would be used together to improve the accuracy in vestigations. All of62Hi strains isolated in this research were nontypeable. Classification test of Pulsed-Field Gel Electrophoresis(PFGE) showed the similarity of42.1%and27types.10types of them came from the same source, and there was geographical relationship. It indicated that there were advantage clones which high-rate spreaded, and if it continually developed, the clones may became dominant strain.In this study, a subset of135Nm strains isolated in Hebei Province from2006to2012was selected for antimicrobial susceptibility test in vitro. The sensitive rates of cephalosporins, chloramphenicol, minocycline, rifampicin, meropenem, azithromycin are all100%. The sensitivity to penicillin drugs decreased, included penicillin and ampicillin, and no drug-resistant strain was found.Resistance rates of quinolones nalidixic acid and ciprofloxacin in135strains of this study was up to85.93%and76.300%respectively. Sulfamethoxazole resistance rate was highest in12kinds of antibiotics,which reaching97.04%, no sensitive strains was found.It conclude that, as preferred drugs, Penicillin-type drugs should be very cautiously used, and as preventative drugs, quinolones should be very cautiously taken too. Sulfa drugs should not be recommend for the prevention and control of epidemic cerebrospinal meningitis. |
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