With the rapid socioeconomic development, increasingly frequent personnel exchanges, and blossoming of tourism, a large number of people enter the natural plague foci for tourism and sightseeing, which greatly increases the chance of exposure to plague-infected animals and vector insects for floating populations. Once plague is transmitted to humans, it will be introduced into the urban areas within a very short period of time by modern means of transport such as airplanes, trains, and automobiles, which increases the risk of prompt transmission of plague. Qinghai province has the natural plague focus of Marmota himalayana which have spread across the province. Based on the tourism development and potential risk of plague in Qinghai province, it will assure and accelerate the healthy development of tourism to take corresponding prevention and control measures according to the practical situation of tourism.

Objective To develop a marmot information collection and reporting system to improve the efficiency of surveillance of epizootic plague in marmots, and to provide a scientific basis for the formulation of plague prevention and control strategy and the basic research. Methods A field investigation was performed in marmot plague foci of Qinghai province, China, 2014, and the spatial distribution and location data of marmots were collected by the Global Positioning System(GPS), involving 352 sample sites of Yushu Tibetan autonomous prefecture, Guoluo Tibetan autonomous prefecture, Wulan county, Jianzha county, Xinghai county, and Qilian county. Five environment variables of height, slope, slope aspect, vegetation coverage, and grassland type, as well as the latitude and longitude of sample sites were obtained. The data of the sample sites were displayed in China Geodetic Coordinate System 2000 using ArcGIS 10.2 software. By analyzing the work requirements and workflow of Marmota himalayana surveillance, database model design, system structure design and system model construction were carried out. Through the application of ArcGIS Runtime SDK for Android related components and the lightweight spatial database supported by SpatiaLite mobile terminals to develop the marmot information collection system in the Eclipse development environment by intergrating various data into the mobile geographic information system platform. Results Based on the habitat information of M. himalayana in natural plague foci of Qinghai province, the established marmot information collection system V3.0 had the following basic functions:management and analysis of plague surveillance data; generation of spatial data, attribute data, and associated pictures, as well as storage and export of spatial data and attribute data with database files; import of data about historical plague foci, route planning, real-time positioning and navigation, route playback, etc. The marmot information collection system changed the traditional paper-based combined GPS, reduced the workload of investigators, and improved the work efficiency. The unified survey method ensured the consistency of data and the standardization of work. Conclusion The marmot information collection and reporting system V3.0 can improve the monitoring mode of marmot plague, increase the probability of detection of animal plague, and assist in making decisions on emergency response to animal or human plague.

Objective To provide a scientific basis for plague prevention and control in Guoluo Tibetan autonomous prefecture, Qinghai province, China (hereinafter referred to as Guoluo prefecture), by etiological analysis and determination of the antibiotic resistance-related genes of Yersinia pestis in that area. Methods A series of experiments including sugar alcohol fermentation test, toxicity test, virulence factor assay, plasmid analysis, and different region (DFR) genotyping were conducted on 13 Y. pestis strains isolated from Guoluo prefecture from 1978 to 2016. According to the gene sequences (aminoglycosides streptomycin-resistant strA and strB; beta-lactam antibiotics-resistant tem and ctx-m; and sulfonamides-resistant sul1 and sul2) published by the National Center for Biotechnology Information (U.S.), a pair of primers were designed for each gene. Polymerase chain reaction (PCR) amplification of the above 6 antibiotic resistance-related genes was carried out using the DNAs from the above 13 Y. pestis strains as templates, to detect whether they carried antibiotic resistance-related genes. Results According to the biochemical grouping, of the 13 test strains, 9 belonged to Qing-Tibet Plateau ecotype, and 4 belonged to Qilian Mountain ecotype. As shown by the results of the toxicity test, all the 13 strains were velogenic strains and 11 contained four Y. pestis-specific virulence factors. The test strains contained 2 types of plasmids with a molecular weight of 6×10 ⁶, 45×10 ⁶, and 65×10 ⁶ versus 6×10 ⁶, 45×10 ⁶, and 52×10 ⁶, respectively. The DFRs were divided into 4 genomovars, i.e., genomovar 5 (7 strains), genomovar 8 (4 strains), genomovar 36 (1 strain), and genomovar 01b (1 strain). In case of valid positive and negative controls, PCR assay of the antibiotic-resistant genes revealed a negative result for all the above 13 Y. pestis strains, and no strain was found to be resistant to streptomycin, beta-lactam antibiotics, or sulfonamides. Conclusion The strains isolated from Guoluo prefecture show the characteristics of Y. pestis from Qinghai-Tibet Plateau. Despite the fact that no antibiotic-resistant strains were found, which demonstrate high toxicity; therefore, it is necessary to enhance plague surveillance and health promotion to prevent plague spreading from animals to humans.

Objective To investigate the etiological characteristics and epidemiological significance of Yersinia pestis strains in Haibei Tibetan Autonomous Prefecture, Qinghai province, and to provide a scientific basis for the prevention and control of plague in this area. Methods Carbohydrate fermentation test, virulence factor detection, virulence determination, plasmid analysis, and different region (DFR) analysis were performed on a total of 104 Y. pestis strains isolated from Qilian, Menyuan, Haiyan, and Gangcha in Haibei Tibetan Autonomous Prefecture from 1956 to 2011. Results According to the biochemical typing, 73 of the 104 strains tested were classified as the Qinghai-Tibet Plateau ecotype, 25 as the Qilian Mountain ecotype, and 6 as the ecotypes different from those in the natural plague foci of Qinghai province. Plasmids with molecular weights of 6×10 ⁶, 45×10 ⁶, and 52×10 ⁶ were found in all of the strains. Seventy-seven (74.04%) of the 104 strains contained four virulence factors, and 98.51% (66/67) were velogenic strains. According to the DFR analysis, six genomovars were found:genomovar 8 (75 strains), genomovar 44 (20 strains), genomovar 5 (6 strains), genomovar 6 (1 strain), genomovar 7 (1 strain), and genomovar 11 (1 strain). Conclusion The Y. pestis strains isolated in Haibei Tibetan Autonomous Prefecture, Qinghai province have the specific characteristics of Y. pestis strains in Qinghai-Tibet plateau, with complex ecotypes and strong virulence. Monitoring, prevention, and control of plague, as well as dissemination of relative knowledge, should be strengthened in this area.

Objective To investigate the epidemic of plague in the past 10 years along the Qinghai-Tibet Railway, and to provide a scientific basis for the prevention and control of plague in future. Methods The monitoring results and clinical data for the human plague epidemic along the Qinghai-Tibet Railway from 2003 to 2013 were collected and analyzed using descriptive epidemiological methods. Results The emergence of plague in both animals and humans mainly occurred in the areas of Geermu (Tanggulashan Township), Tianjun, and Wulan in the Qinghai section of the Qinghai-Tibet Railway from 2003 to 2013. Sixty-nine strains of Yersinia pestis and 86 sera with positive F1 antibody were detected in these areas; 7 cases of human plague occurred, and 3 cases died. Conclusion Serious epidemic of plague remains in the Qinghai section of the Qinghai-Tibet Railway. Frequent occurrence of plague between animals and sporadic human plague epidemic are mainly related to illegal marmot hunting in these key areas.

Objective To investigate the epidemic of plague in the past 10 years along the Qinghai-Tibet Railway, and to provide a scientific basis for the prevention and control of plague in future. Methods The monitoring results and clinical data for the human plague epidemic along the Qinghai-Tibet Railway from 2003 to 2013 were collected and analyzed using descriptive epidemiological methods. Results The emergence of plague in both animals and humans mainly occurred in the areas of Geermu (Tanggulashan Township), Tianjun, and Wulan in the Qinghai section of the Qinghai-Tibet Railway from 2003 to 2013. Sixty-nine strains of Yersinia pestis and 86 sera with positive F1 antibody were detected in these areas; 7 cases of human plague occurred, and 3 cases died. Conclusion Serious epidemic of plague remains in the Qinghai section of the Qinghai-Tibet Railway. Frequent occurrence of plague between animals and sporadic human plague epidemic are mainly related to illegal marmot hunting in these key areas.

Objective To determine the flea fauna and distribution in Three Rivers’ Headwaters region of Qinghai province. Methods Based on the results of the investigation and surveillance on plague foci, fleas were collected in vitro from the captured small mammals in the regions, and taxonomic identification was conducted. Results A total of 104 species of fleas had been found in Three Rivers’ Headwaters region in Qinghai (including sub?species), belonging to 33 genera, 6 families, the dominant species being Ceratophyllidae, Leptopsyllidae and Ctenophthalmidae, accounting for 33.65% (35/104), 27.88% (29/104) and 24.04% (25/104), respectively. Thirty four species, 16 genera and 33 families in the Qiangtang Plateau sub?region, 100 species, 16 genera and 6 families in South Tibet sub?region were also found, including 28 unique species in Three Rivers’ Headwaters region. Conclusion Further biological investigation on fleas should be strengthened along with vector control research in order to provide data for the prevention and control of plague.

【Abstract】 This paper briefly discusses the biology and ecological characteristics of host animals and vectors infected naturally by Yersinia pestis district and the time and location of first isolation in Sanjiangyuan. It is to understand the species of animals and vectors infected and the function they plays in the plague epidemiology in order to provide the basis for the prevention and control of plague in Sanjiangyuan.