Objective To identify rodent residues using DNA barcoding technology in plague areas of Shaanxi and to analyze the feasibility of DNA barcoding method.Methods DNA extraction,PCR,electrophoresis and sequence determination and alignment were used to determine the cytochrome C oxidase Ⅰ (COI) gene sequence from 62 residues of 7 species identified by morphology in 8 different parts.COI gene sequence was analyzed using BLAST software of American National Center for Biotechnology Information (NCBI) for sequence homology comparison and the phylogenetic tree was constructed by using the neighbor joining(NJ)method of COI gene sequence.Results In addition to the hair,CO I genes of the feet,the tail,the fur,the muscle,the ribs,the ear,and the eye were amplified,respectively,and the size of amplified fragment was similar to the size of the product with an expected fragment(700 bp),and the fragment was a single band.COI genes of 59 residue specimen were obtained by DNA sequencing and there were high degree of homologies between CO I gene sequences of Meriones unguiculatus,Cricetulus barabensis,Meriones meridianus,Dipus sagitta,Phodopus roborovskii,Rattus norvegicus and Allactaga sibirica and their corresponding host genes in NCBI(99.0％,98.1％,99.8％,98.9％,99.5％,99.1％,98.3％).NJ method showed that 7 NJ phylogenetic trees were constructed with COI sequence of 59 species residues.The CO I sequences of same rodent with different residues were clustered into one group.Condusion DNA barcoding technology can identify host animal residues in plague areas,and the identification results are reliable.

We studied the genetic characteristics of Spermophilus in Shaanxi Province,China.The COI,Cyt-b gene were sequenced and the results were compared with those of dauricus from Inner Mongolia Keyouzhong Banner and Zhengxiangbai Banner,and S.alaschanicus from Haiyuan County of Ningxia.And genetic distance was analyzed and Neighbor-Joining tree was built.Results showed that the genetic distance of COI gene sequences between Spermophilus from Dingbian County in Shaanxi and S.alaschanicus in Ningxia was ≤0.5％,and the genetic distance was ranged from 7.9％ to 9.3％ with Citellus dauricus from Inner Mongolia.The genetic distance of Cyt-b gene between Spermophilus from Dingbian County in Shaanxi and S.alaschanicus in Ningxia was ≤2.2％,and ranged from 8.9％ to 11.2％ with Citellus dauricus from Inner Mongolia.The Neighbor-Joining tree of COI,Cyt-b gene showed two major clusters.One of them were clustered by Spermophilus from Dingbian County in Shaanxi and S.alaschanicus in Ningxia,and another one was Citellus dauricus from Inner Mongolia.The Neighbor-Joining tree of COI gene showed that all samples from Shaanxi Province clustered in a group.In conclusion,the Spermophilus in Shaanxi Province were S.alaschanicus.

Objective To apply DNA barcoding technology for exploring its taxonomic status and differences in the molecular biology of Cricetulus barabensis in Shaanxi Province.Methods Sixty-five samples of Cricetulus barabensis were collected from Dingbian,Jingbian Counties in northern of Shaanxi and Dali County in Guanzhong plain (Dingbian 58 samples,Jingbian 2 samples,and Dali 5 samples).According to the mitochondrial cytochrome C oxidase subunit I gene (CO I) sequence,the genetic distance was calculated and Neighbor-Joining tree was constructed.Results The genetic distance between two samples (13.16,13.21) and other 56 samples of Dingbian was 9.2％-10.0％.The genetic distance between the 56 samples of Dingbian and Jingbian was less than 1％ and Dali was 7.2％-8.3％;the average intraspecific genetic distance of Jingbian and Dali was less than 1％.The Neighbor-Joining tree showed that all the Cricetulus barabensis samples from the three counties were separated into two large branches.The samples of 13.16,13.21 from Dingbian together were classified into a class and the rest of the samples into another separate branch.At the same time,other samples from Dingbian except 13.16,13.21 and Jingbian were distributed in a small branch,and Dali samples were occupied another small branch.Conclusion Using the DNA barcoding technology,we have determined three subspecies of Cricetulus barabensis in Shaanxi Province,Dingbian has two kinds and Dali has a different subspecies.

Objective To learn the diagnosis and treatment of brucellosis patients in Suide County of Shaanxi Province in 2015,and to provide a scientific basis for making accurate prevention and control measures.Methods All the cases diagnosed as brucellosis in Suide County from January 1 to December 31 in 2015 and lived in this county were retrospectively investigated by case questionnaire survey,including basic information,medical procedures,and epidemiological contacts.Descriptive statistical analysis was performed using SPSS 18.0 software.Results In 2015,75 cases of brucellosis were diagnosed in Suide County,75 questionnaires were distributed,with 53 completed questionnaires returned.The average age of respondents was (49 ± 14) years old,of which 84.9％ (45/53) were male and 94.3％ (50/53) were farmers,except one case was actively monitored by Suide County Centre for Disease Control and Prevention then treated,the rest of the patients were treated after the onset of the disease.Of the 52 patients,one patient was diagnosed after one visit,accounting for 25.0％ (13/52);one patient was diagnosed after at least 4 visits,accounting for 3.8％ (2/52).The cumulative diagnosis rate at provincial-level hospitals was 1/3 and that at disease prevention and control institutions was 92.7％ (51/55),there were no confirmed cases in municipal hospitals,county hospitals,township hospitals,village clinics and individual clinics.For the first reason to see a doctor,65.4％ (34/52) of the patients were fever or accompanied by sweating,fatigue,arthralgia and waist and leg pain.The medians from onset to treatment between the first diagnosis,and 2,3,4 visits were 15,18,27,45 days,respectively;the median from onset to diagnosis was 21 days,ranging from 2 to 182 days.Totally 84.9％ (45/53) patients had a history of exposure to animals,of which 97.8％ (44/45) had contacted the sheep.Conclusions The cases in Suide County are mainly adult male farmers,and the diagnosis rate at hospitals below municipal level is low.It is recommended to strengthen the health intervention of high-risk groups and improve the level of diagnosis and treatment of primary medical staff.

Objective To apply the DNA barcoding technology for identification on host animal and to establish the host animal DNA bar code database on natural foci of plague in Shaanxi.Methods 139 host animals belonging to 3 orders,6 families and 12 genera and 62 residues belonging to 7 species from 8 different parts of the province,were detected.DNA barcoding technology was used to analyze the DNA CO Ⅰ gene sequence on the natural foci of plague in Dingbian county.Results The intra-specific genetic distance was less than 2％ while the inter-specific distance ranged from 8.9％ to 15.1％.Fourteen major clusters were apparently showed on a Neighbor-Joining tree.Residue samples could be detected regarding the objective gene.Alashan ground squirrel was previously noticed to carry 14 major clusters,which were previously mistakenly named as Citellus dauricus in Dingbian county.Conclusion DNA barcoding technology could overcome the shortcomings caused by the morphological identification so could be used to identify the host animal and residues in the natural focus of plague.

Objective To investigate the ability in diagnosing and reporting brucellosis of primary medical personnel in Suide County of Shaanxi Province,and provide scientific basis for making prevention and control strategies.Methods Convenience sampling method was adopted in October 2016.A questionnaire survey was conducted among the county hospitals,township hospitals,village clinics and individual clinics in Suide County to collect information on the ability in diagnosing and reporting brucellosis of primary medical personnel.The specific content includes the basic information,the awareness of brucellosis diagnosis and reporting capabilities,the situation of brucellosis training,and the views about the diagnosis of brucellosis.SPSS 18.0 software was used to carry out descriptive statistical analysis.Results A total of 77 primary healthcare workers were surveyed.Their average age was (38 ± 9) years old,57.1％ (44/77) workers were undergraduates,and 53.2％ (41/77) were working in county hospitals.9.1％ (7/77) were completely aware of the major infectious diseases,29.9％ (23/77) were fully aware of the transmission mute,28.6％ (22/77) and 66.2％ (51/77) known the high risk population and the epidemiological history of brucellosis.Twenty-six percent (20/77) of the medical staff were thoroughly aware of the main clinical manifestations,68.8％ (53/77) were clearly aware of the clinical stage of brucellosis;24.7％ (19/77) could understand the specificity of the laboratory tests of brucellosis;44.2％ (34/77) had a strong ability in reporting brucellosis.71.4％ (55/77) of the medical staff received the training about the knowledge of brucellosis;49.4％ (38/77) thought that the clinical manifestation was the most difficult to grasp in the criteria about diagnosis of brucellosis.Conclusions The ability of diagnosis and reporting of brucellosis is weak in primary healthcare workers in Suide County,the epidemiology and clinical knowledge of brucellosis are not comprehensive.It is suggested to strengthen the understanding of brucellosis among medical staff,especially in primary healthcare workers.We should carry out the training of disease epidemiology and clinical knowledge of brucellosis and standardize patient management.

Objective To introduce the concept of health promotion to brucellosis comprehensive prevention and control and then the effect was evaluated.We expect this article could provide scientific basis for prevention and control of brucellosis.Methods The study began in March 2014,a high-incidence district of brucellosis in Dali County was selected.Our study populations were divided to primary target groups and secondary target groups by the extent of exposure to sheep.We implemented general health campaigns,targeted health education,intervention and inducement,promotion of establish leading groups,and released relevant policies and rules for target population.According to the information from the questionnaire survey designed by us,before and after the intervention,the difference between the awareness rate of knowledge on brucellosis control,the health behavior formation rate and the effects of different intervention measures in primary target groups,were compared.The correct diagnostic rate in time (in 3 months),the eligible rate of trained health works,the change of the incidence of brucellosis in human cases,the perfection of the relevant policies on brucellosis control were analyzed,and the effectiveness of comprehensive prevention and control and health promotion strategies were evaluated.Results The disease awareness rate of target audience was 62.49％ (12 695/20 315) after the intervention which was 20.23％ (3 746/18 517) before the intervention.The awareness rate of primary target groups and secondary target groups was increased by 39.69％ [before intervention:33.75％ (1 624/4 812),after intervention:73.44％ (3 569/4 860)] and 43.57％ [before intervention:15.48％ (2 122/13 705),after intervention:59.05％ (9 126/15 455)],respectively.South of Luohe and north of Luohe increased by 37.70％ [before intervention:36.81％ (731/1 986),after intervention:74.51％ (1 453/1 950)] and 35.86％ [before intervention:35.06％ (711/2 028),after intervention:70.92％ (1 366/1 926)] after the intervention.The success rate of prevention and control skill on brucellosis in medical staff was 88.52％ (594/671);the correct diagnostic rate of new cases was 93.73％ (370/383).The proportion of new cases in the selected county in 2014 was 18.26％ (269/1 473) of the whole Shaanxi Province,the ratio decreased compared to that of the previous year.The proportion of new cases in 2015 was 6.14％ (75/1 221).The proportion of new cases in 2016 was 3.48％ (33/948).Conclusions Through the implementation of health promotion,health education and health promotion comprehensive measures,the disease awareness rate in target population has increased substantially.These measures are also able to lead focused population to develop health behavior and to decrease the incidence of brucellosis among people,and to realize the sustainable control of human brucellosis.

Objective:To analyze the incidence of brucellosis and the genotypes of Brucella isolates or nucleic acids in Shaanxi Province, to get the epidemiological and molecular genetic characteristics, and to provide scientific basis for precise prevention and control of human brucellosis. Methods:Log into the Chinese Disease Control and Prevention Information System, collect the incidence data of human brucellosis of Shaanxi Province in 2020, and analyze the epidemiological characteristics. Bacteriology and PCR methods were used to identify the isolates or nucleic acids, and multiple locus variable-number tandem repeat analysis (MLVA) was used for molecular typing. BioNumerics (Version 7.6) software was used to analyze the results of MLVA.Results:In 2020, 1 086 cases of human brucellosis were reported in Shaanxi Province, the incidence rate was 2.80/100 000, involving 86 counties (districts), the epidemic peak was from March to September (865 cases), male-to-female ratio was 2.68 ∶ 1.00 (791 ∶ 295), 79.74% (866 cases) in the age group of 30 to 69 years old, and 83.43% (906 cases) of the cases were farmers. Biotype identification of 36 isolates showed that 4 isolates were mutant Brucella melitensis, 3 isolates were Brucella melitensis 1 and 29 isolates were Brucella melitensis 3. The 36 isolates and 7 nucleic acids were identified as Brucella by BCSP31-PCR and Brucella melitensis by AMOS-PCR. MLVA-16 genotyping, panel1 showed two genotypes: type 42 (1-5-3-13-2-2-3-2) and type 63 (1-5-3-13-2-3-3-2), panel2A showed 4-41-8 and panel2B showed high variability. Thirty-six isolates and 7 nucleic acids were divided into 33 genotypes, of which 27 genotypes were single isolates and 6 genotypes were shared. Conclusions:The situation of human brucellosis prevention and control in Shaanxi Province is grim. MLVA-16 is a mature genotyping method, which determines the existence of multiple genotypes of Brucella isolates or nucleic acids in Shaanxi Province, which can provide scientific information for precise prevention and control of human brucellosis, outbreak analysis and epidemiological traceability.

Objective:To understand the changes of brucellosis prevention and control knowledge awareness among breeders in Chunhua County, Xianyang City, Shaanxi Province before and after the publicity intervention.Methods:A multi-stage cluster sampling method was adopted to select 10 townships with more reported cases of human brucellosis in Chunhua County from January 2019 to June 2020, and each township was given priority to select the administrative village with the largest number of reported cases for investigation. At least 20 breeders aged 20 years old and over in each administrative village were selected, and if the number was insufficient, supplementary surveys would be conducted in other administrative villages with the larger number of breeders in the township. Questionnaire survey was conducted on all subjects, including general demographic characteristics, brucellosis prevention and control knowledge and related protective behaviors. After the baseline investigation, 6 months of brucellosis prevention and control knowledge publicity was carried out in the administrative villages included in the investigation, and the awareness rate of brucellosis prevention and control knowledge before and after the publicity intervention was compared to evaluate the effect of publicity intervention.Results:After the publicity intervention, a total of 240 breeders were investigated, and 176 people were aware of brucellosis prevention and control knowledge, with an overall awareness rate of 73.33% (176/240), which was significantly higher than that before the publicity intervention (57.50%, 115/200), and the difference was statistically significant (χ 2 = 12.21, P = 0.005). After the publicity intervention, the awareness rates of breeders on "can cattle and sheep transmit diseases to humans" and "do you know that cattle and sheep can only be purchased after passing the quarantine inspection" were relatively high, they were 95.83% (230/240) and 95.00% (228/240), respectively, and the differences were statistically significant (χ 2 = 50.04, 112.64, P < 0.001) compared with that before the publicity intervention [71.50% (143/200) and 51.00% (102/200)]. The awareness rate of breeders on "how brucellosis is transmitted from livestock to humans" was the lowest, it was 53.33% (128/240), which was not significantly different (χ 2 = 0.82, P = 0.370) from that before the publicity intervention (49.00%, 98/200). Conclusions:After the publicity intervention, the overall awareness rate of brucellosis prevention and control knowledge of breeders in Chunhua County has improved, but the awareness rate of some individual issues is still low. It is suggested to strengthen the pertinence of publicity and education.

Objective:To analyze the epidemic characteristics of human brucellosis in Xianyang City, Shaanxi Province, to grasp the epidemic trend and provide scientific basis for further prevention and control of human brucellosis.Methods:Descriptive epidemiological methods were used to statistically analyze the incidence data and epidemic data of human brucellosis in Xianyang City, Shaanxi Province from 2011 to 2020 in the "Infectious Disease Surveillance System of China Disease Control and Prevention Information System".Results:A total of 864 human brucellosis cases had been reported in Xianyang City from 2011 to 2020, and there was no dead case. The annual incidence began to increase rapidly from 2014, the highest annual incidence in 2019 was 5.79/10 5. There were statistical differences between the incidence of different years (χ 2 = 900.40, P < 0.001). Human brucellosis cases in Xianyang City were mainly concentrated in dairy goat breeding counties, with a total of 571 cases reported, accounting for 66.09%. Cases were reported in all months of the year, and the peak incidence of human brucellosis was from April to August, accounting for 64.35% (556/864). The age of cases was mainly concentrated in the 40 - 69 years old group, accounting for 68.29% (590/864); the ratio of male to female was 2.40 ∶ 1.00 (610 ∶ 254). The occupation was mainly farmers, accounting for 83.45% (721/864). There had been an increase in the proportion of scattered children, students and preschool children. The total serological positive rate was 3.14% (283/9 009) in Xianyang City, and pathogenic culture showed variant strains. The median of interval between onset time and diagnosis time was 8 days. Conclusion:The prevalence of human brucellosis in Xianyang City, Shaanxi Province shows an overall upward trend, which needs to be paid more attention to and control efforts should be strengthened.