Objective To investigation the plague health education methods and content to meet the need of different people in Kangbao county of Hebei province, and lay a solid foundation for targeted health education and achieve better results. Methods An anonymous questionnaire was conducted to investigate 387 residents in Kangbao county. Results The targeted group's lower rates of knowing were "the treatment of sudden high fever after contact the plague animals or bite with flea"(8.56%), "Kangbao county is the plague natural foci"(20.72%), and "the symptoms of the plague patients"(28.45%). Different occupations need different ways of plague health education(χ²=105.118, P<0.01). Correspondence analysis found that farmers and broadcast,students and lectures, workers and broadcast, cadres and the micro-channel all have strong correlations. The 76.14% of farmers choose broadcast, 66.30% of students choose lectures, and the doctors prefer brochure(37.10%) and TV(37.10%). In addition to the panels, newspapers and text message, the workers like other publicities. The leaders like the other publicities except the panels. Conclusion Use radio and television primarily to strengthen the propaganda for farmers. Organize more health education lectures in school for students. For workers and cadres, take a variety of ways of health education, for example, broadcasting, WeChat and text message. Doctors, considering the professional particularity, should be trained and assessed professionally to improve their emergency relief capability.

Objective To study the genotype and epidemiological characteristics of Yersinia pestis in Hebei foci. Methods Primers were designed according to the confirmed 22 different segments (DFR), to genotype the 116 Y. pestis DNA of Hebei province. Results All of the strains lack these DFR of 01, 06, 07, 13, 15-18, to compare the genetic typing system of DFR, Y. pestis from Hebei province belong to the 17 genotype, distributed in the northern Kangbao county neighboring Huade, Baiqi, and Taipusiqi in the Inner Mongolia Autonomous Region. Conclusion The Y. pestis is stable genetically in Hebei plague foci, and have only one genotype, so the epidemic tends to stabilize.

Objective To evaluate enzyme immunostaining technique for detection of F1 antigen of Yersinia pestis in rodents. Methods Visceral organ specimens of 266 mice infected with virulent Y. pestis and 207 control rodent specimens were detected by horseradish peroxidase labeled plague F1 monoclonal antibody (HRP-F1McAb) enzyme immunostaining technique, and in comparison with the RIHA and RGICA methods．Results Coincidence was 98.52% between HRP-F1McAb enzyme immunostaining technique and RIHA, Kappa=0.970, and the difference was statistically significant in the positive detection rates (χ²=5.140, P=0.016); Coincidence was 98.50% between HRP-F1McAb enzyme immunostaining technique and RGICA, Kappa=0.901, with statistically insignificant difference in the positive detection rates (χ²=0.250, P=0.625). Sensitivity of HRP-F1McAb enzyme immunostaining technique was 100%, specificity was 97.02%, positive predictive value was 97.14%, negative predictive value was 100%, and Youden index was 0.970． Conclusion The enzyme immunostaining technique is sensitive and specific, fast and simple in detection of plague F1 antigen. It is a valuable detection technique in early and rapid diagnosis of plague in rodents．

Objective To study the genotype of Yersinia pestis in Hebei plague foci by variable number of tandem repeat (VNTR). Methods Primers were designed according to the confirmed 14＋12 VNTR, to genotype the 116 Y. pestis DNA of Hebei province. Results All of the strains showed one genetype, but they were different from CO92 and EV. Conclusion There is only one genetype of plague, indicating a genetic stability in Y. pestis in Hebei province.

The plague is categorized as a Class A infectious disease in China. Plague foci are widely distributed, and strains have different features and varied virulence in China. It is of great significance for deducing the sudden outbreak of plague and terrorist attack detection, with the strains of different foci for genotyping. The choice of tandem repeats loci is the key of the multiple loci vntr analysis (MLVA) classification results. This assay mainly introduces tandem repeats in Yersinia pestis genotyping in application progress, and provides a reference for other workers in genotyping.

Objective To characterize the genosome of 116 Yersinia pestis strains isolated from plague foci in Hebei province in China. Methods All the strains were detected by polymerase chain reaction (PCR) with 15 pairs variable number tandem repeat (VNTR) provided by China CDC, then the length of results were analyzed. Results The numbers and lengths of the repeat sequences from all strains are same with the single primer, and different with the different primers, such as the length of all stains with the prime M52 is 153 bp, and the number of the repeat sequences is 3, then with the prime M59, the length and the number is 250 bp and 3 respectively. Conclusion Multiple loci VNTR analysis (MLVA) genetic typing is reliable, and it is stable genetic mark of Y. pestis from Hebei province. To build the database of the plague with MLVA is useful for the investigation of the plague variation and source.

Objective To analyze the current running status of plague control and management information system in Hebei province, China, and to improve the accuracy and reliability of the data obtained from the system. Methods Plague surveillance monthly reports were compared with the direct network report data. Analysis and discussion were made on the problems emerging from the application of the system, as well as the issues identified from the work. Results The system operated smoothly, but problems remained such as cumbersome data entry procedures, incomplete data entry, and data entry error. Incomplete data entry was the most outstanding problem in direct network report, and for example, the net rate was 53.0%-80.2% for the pathogenic test, 25.0%-63.0% for the serum test, 66.0%-80.0% for the quadrant survey, and 42.3%-73.6% for the small rodent survey. Conclusion The plague control information system should be optimized and the team of primary health care staff should be strengthened in order to increase the accuracy and reliability of the network report and to improve the value of the system.

To further study the structure and nature of the foci of plague in Hebei province, this article summarizes the biological characteristics of Yersinia pestis isolates in the regions by analyzing the large amounts of data collected. By introducing the biochemical characteristics, nutritional needs, plasmid characteristics, virulence factors, virulence and toxins and other aspects, the study has concluded that Y. pestis isolated in Hebei province belongs to Group B of the Ordos Plateau, of which the nutritional needs are characterized by glycine semi-dependence and tryptophan dependence. These strains contain 4 kinds of plasmids, of which 13×106 plasmid is specifically carried by Meriones unguiculatus in the Inner Mongolian. Some strains lack the 45×106 plasmid, though all of isolates were F1 antigen and streptozotocin (PstⅠ)-positive. However, only a certain portion of the strains were positive for pigmentation (Pgm) and VW antigen, indicating genetic instability and moderate toxicity.

【Abstract】 Objective To study  the  practicability  of  double  antigens  sandwich  enzyme  linked  immunosorbent  assay（DAgS?ELISA）on the detection of Yersinia pestis F1 antibodies. Methods A total of 558 samples antibodies of anti?F1 antigen were detected by DAgS?ELISA and trace indirect hemagglutination assay (trace?IHA). Results Thirty three samples were positive tested by IHA, 31 positive by DAgS?ELISA, the positive accordance rate was 90.91%, 99.81% for negative accordance rate, 99.28% for the total accordance rate. The positive rate detected by IHA and DAgS?ELISA were 5.91% and 5.56% respectively, and no statistics difference was found (χ2＝0.25，P＝0.625). About 27 the immuno?serum were positive detected by IHA and DAgS?ELISA methods, and the sensitivity of IHA test were all higher than that of DAgS?ELISA (t＝3.023, P＝0.006). Conclusion Sensitivity of DAgS?ELISA is lower than that of trace?IHA, but its specificity is better and no primary inhibitory phenomena, and could exempt from leak detection in the preliminary screening.