Serological Survey of Zika Virus in Humans and Animals in Dejiang Prefecture, Guizhou Province, China / 生物医学与环境科学（英文）

OBJECTIVE@#The current outbreak of Zika virus (ZIKV) poses a severe threat to human health. Two ZIKV strains were isolated from mosquitoes collected from the Dejiang prefecture in China in 2016, which was the first isolation of ZIKV in nature in China.@*METHODS@#In this study, serum samples were collected from 366 healthy individuals and 104 animals from Dejiang prefecture in 2017, and the plaque reduction neutralization test (PRNT) was used to evaluate the seroprevalence of ZIKV.@*RESULTS@#None of the 366 residents from whom the samples were collected were seropositive for ZIKV. None of the 11 pigs from whom the samples were collected were seropositive for ZIKV, while 1 of 63 (1.59%) chickens and 2 of 30 (6.67%) sheep were seropositive for ZIKV.@*CONCLUSION@#The extremely low seropositivity rate of ZIKV antibodies in animals in the Dejiang prefecture, Guizhou province in this study indicates that ZIKV can infect animals; however, there is a low risk of ZIKV circulating in the local population.

Fat-to-muscle Ratio: A New Anthropometric Indicator for Predicting Metabolic Syndrome in the Han and Bouyei Populations from Guizhou Province, China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the prevalence and possible factors influencing metabolic syndrome in people from Guizhou Province and to explore the predictive value of the fat-to-muscle ratio in diagnosing metabolic syndrome.</p><p><b>METHODS</b>A multistage stratified sampling method was used in this cross-sectional study of 20-80 years old Han and Bouyei populations from Guizhou Province, southwestern China, from October-December 2012. The study included 4,553 cases of metabolic syndrome, that was defined according to 2005 International Diabetes Federation criteria. The receiver operating characteristic curve was used for determining the sensitivity, specificity, and predictive ability of the fat-to-muscle ratio for the diagnosis of metabolic syndrome.</p><p><b>RESULTS</b>The age-standardized prevalence of metabolic syndrome was 11.38% (men: 9.76%; women: 12.72%) for Han and 4.78% (men: 4.43%; women: 5.30%) for Bouyei populations. In Guizhou Province, the cut-off value for the men fat-to-muscle ratio was 0.34, the area under the curve was 0.95, and the sensitivity and specificity were 0.94 and 0.85, respectively. The cut-off value for the women fat-to-muscle ratio was 0.55, the area under the curve was 0.91, and the sensitivity and specificity were 0.93 and 0.79, respectively.</p><p><b>CONCLUSION</b>The fat-to-muscle ratio is highly predictive of metabolic syndrome in Guizhou Province, and a useful reference indicator.</p>

Genotype features of norovirus associated with acute gastroenteritis through sentinel surveillance in Guizhou Province, 2011 / 病毒学报

To study the genotype of Norovirus associated with acute gastroenteritis in Guizhou Province 2011, the patients' fecal specimens were collected from the Guizhou Province People's Hospital in the period of May to December 2011. Noroviruses in specimens were detected by a real-time reverse transcription polymerase chain reaction (Real-time RT-PCR). VP1 genes of norovirus-positive strains were then cloned and sequenced. Out of 70 clinical samples, the positive rates for norovirus G I (1 strain) and G II (34 strains) were 1.43% and 48.57, respectively. The VP1 sequencing results of seven norovirus G II showed thatthree strains were genotype G II . 4 and four strains were genotype G II . 3 Those genotype GIL . 4 strains were new variants (GII . 4 2011),closest to GII . 4 2006b variant. One amino acid appeared back mutation. Those genotype G II . 3 strains were divided into 2 gene clusters. One cluster was closest to Korean strain (HM635118) and Shanghai strain(GU991355). One cluster was closest to Japaness strain (AB629943) and 2007 Indian strain (EU921389), Four amino acids appeared back mutations.

Analysis on molecular epidemiological features of enterovirus type 71 in Guizhou Province, 2008-2011 / 病毒学报

To study the genotype and molecular epidemiological features of enterovirus type 71 (EV71) in Guizhou Province. The hand-foot-mouth disease(HFMD) patients since 2008 in Guizhou Province were surveyed. EV71 RNA positive samples, including mild cases, death cases and cases of serious conditions, were used for subsequent cell culture and sequencing of VP1 complete gene. Genotypes were compared between domestic and foreign epidemic strains. The results showed that the main pathogenwas EV71 subtype C4a in 2008, 2009 and 2011. The nucleotide homology was 95. 3 - 99. 7% among 109 sequenced strains isolated in Guizhou Province. Guizhou strains were more similar to the representative strains from neighbor Province or City, including Shandong, Shanghai, Nanjing, Jilin and Ningbo. There was no distinct sequence difference among the isolates from either of death, mild case or case of serious condition at the nucleotide and amino acid levels. The diversity of nucleotide sequence of isolates was less within same region and year than those trans-regional strains or strains in different year.

Identification and genetic characteristics on the bacteria isolate from a case of human Brucellosis in Guizhou province / 中华流行病学杂志

<p><b>OBJECTIVE</b>A suspected Brucella (B.) strain(GZZA), isolated from a case of anti-Brucella antibody positive patient was identified and its' genetic characteristics was analyzed, to provide etiologic basis for the confirmation of patient in Guizhou province.</p><p><b>METHODS</b>Conventional methods and polymerase chain reaction(PCR)were used to identify the bacteria strain, with genetic characteristics analyzed by MLVA-16.</p><p><b>RESULTS</b>The bacteria strain was identified as B. melitensis biovar 3 under the conventional and PCR methods. Results from the MLVA-16 analysis indicated that the bacteria strain was closely clustered with B. melitensis biovar 3, and differences of repeated numbers at VNTR loci bruce42, bruce04, bruce09 and bruce16 were also displayed.</p><p><b>CONCLUSION</b>Both traditional and molecular methods to identify one bacteria strain isolated from the human patient as B. melitensis biovar 3 and the genetic characteristics of the strain was closely related to that of B. melitensis biovar 3. Differences of repeated numbers at part of VNTR loci were also showed. The results of this study provided etiologic evidences for the confirmation of Brucella infection of the patient, also providing scientific basis for the control and prevention of Brucellosis in Guizhou province.</p>

Fever monitoring program in areas with high incidence of typhoid and paratyphoid fever in Guizhou province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the incidence rates of both typhoid fever and paratyphoid fever in the high prevalent areas of Guizhou province so as to provide evidence for the development of programs on comprehensive intervention and effectiveness evaluation.</p><p><b>METHODS</b>Six townships in Pingba county were selected as intervention areas while six townships in Kaiyang county were taken as control. All hospitals and clinics were classified into A, B and C types according to its level and the capacity of the blood culture. Surveillance on typhoid and paratyphoid fever was conducted based on all population and all hospitals, clinics and county CDCs among the patients with unknown fever.</p><p><b>RESULTS</b>In the surveillance area in those two counties, there were 12 944 blood samples from patients with unknown fever which have been tested and cultured. Among them, 200 strains of Salmonella including 16 typhoid strains, 184 paratyphoid A strains were identified, with the total positive rate as 1.55%. The positive rate before the intervention program was higher than the after. The detection rate was 1.91% in the type A hospitals. 39 strains of Salmonella have been cultured from 2039 samples which accounting for 19.50% (39/200) of the total strains. 4315 blood samples were cultured at the 'Class B' sites which isolated 82 strains of Salmonella, accounting for 41.00% (82/200), with a detection rate as 1.90%. 6590 samples were cultured at the 'Class C' sites, which identified 79 strains of Salmonella, accounting for 39.50% (79/200), with a detection rate as 1.20%. The detection rate was much higher before the use of antibiotics than after using them (P < 0.05). The annual peak time of positive detection was in spring and fall. The outbreaks or epidemics often appeared in the same places, with farmers, students as the high-risk populations. Symptoms of both typhoid and paratyphoid fever were not typical.</p><p><b>CONCLUSION</b>Typhoid and paratyphoid monitoring programs which covered primary health care institutions in the high incidence area seemed to be effective in reflecting the pictures as well as the burden of both typhoid and paratyphoid.</p>

Etiologic diagnosis and analysis of the first case of human brucellosis in Guizhou province / 中国地方病学杂志

Objective To etiologically diagnose and analyze a patient with suspected cases of brucellosis,and to provide a experimental basis for the confirmation of the first case of human brucellosis in Guizhou province.Methods Conventional and molecular techniques [genus specific Brucella surface protein 31 PCR (BCSP31-PCR)and Brucella suis species-specific PCR (AMOS-PCR)] were used to identify suspicious bacteria strains isolated from the suspected patient of brucellosis.Results The results showed that the Brucella suspicious colonies were identified as Brucella melitensis biotype 3 using conventional tests and were further identified as Brucella spp.by genus specific Brucella surface protein 31 PCR (BCSP31-PCR) and classified as Brucella melitensis with Brucella abortus,Brucella melitensis,Brucella ovis,Brucella suis species-specific PCR(AMOS-PCR).Conclusions Laboratory diagnostic results show that the bacteria strain isolated from the suspected patient of brucellosis is Brucella melitensis biotype 3.It is the first case of human brucellosis in Guizhou province.

Analysis of the genetic differences in the nucleoprotein between rabies virus and its vaccine strains in Guizhou province from year 2005 to 2010 / 中华预防医学杂志

<p><b>OBJECTIVE</b>This study was to explore the differences in the nucleoprotein gene between rabies virus (RABV) and its vaccine strains in Guizhou province from year 2005 to 2010.</p><p><b>METHODS</b>Samples from 4 rabies patients and cerebral tissue samples of 28 rabies infected dogs were collected from different districts in Guizhou province between year 2005 and 2010. Direct Immunofluorescence Assay (DFA) and RT-nested PCR assay were applied to detect the overall length of N gene sequence. Meanwhile, based on the comparison between the homology and phylogenetic tree, the differences in N gene sequence between the prevalent RABV and the RABV vaccine strains collected from NCBI database in these years.</p><p><b>RESULTS</b>According to DFA and RT-nested PCR assay, the antigen and nucleic acid of the 21 dogs and 4 human samples were both confirmed positive; whose full length of N gene sequences were both 1353 bp. The homological analysis showed that the 25 strains of RABV virus and the RABV type I virus stored by GenBank database shared a high homology in N gene nucleotide and amino acid sequences, which were 89%-100% and 98%-100%, respectively. Besides, the homology between the 25 strains of RABV virus and its vaccines in nucleotide and amino acid sequences were separately 86%-95% and 96%-100%. The N gene of vaccines for livestock shared the highest homology with HEP-Flury strain in the nucleotide and amino acid, which were 88%-89% and 98%-99%, respectively. The vaccines for human use showed its greatest homology with the CTN strain in nucleotide (86%-100%) and amino acid (96%-100%). The phylogenetic tree analysis indicated that the 25 strains of RABV virus, RABV type I virus and the CTN vaccine strains constituted one individual cluster, which was least different from the CTN vaccine for human use.</p><p><b>CONCLUSION</b>The prevalent RABV virus, the vaccine HEP-Flury for livestock and the vaccine CTN for human use were found to be highly similar in N gene expression in Guizhou province from 2005 to 2010.</p>

Molecular typing of Leptospira interrogans strains isolated from Rattus tanezumi in Guizhou Province, Southwest of China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To identify and type three leptospires isolated from Rattus tanezumi in Guizhou Province by using three molecular techniques (PFGE, MLVA, and MLST), reveal the molecular characteristic of causative agents of local leptospirosis and evaluate these three molecular methods based on their detection resolution and efficiency.</p><p><b>METHODS</b>Three Leptospira strains were isolated from the kidney of Rattus tanezumi and cultured with EMJH medium. PFGE, MLVA, and MLST assays were applied to type the three strains isolated from Rattus tanezumi in Guizhou Province.</p><p><b>RESULTS</b>PFGE, MLVA, and MLST typing showed that the three leptospiral isolates matched with leptospiral serogroup Icterohaemorrhagiae serovar Lai. The findings of the genotyping methods were consistent. MLVA and MLST defined genotypes, whereas PFGE allowed the recognition of additional subgroups within the genotypes, and the findings of molecular typing were also consistent with those of traditional techniques.</p><p><b>CONCLUSION</b>Three leptospiral isolates from Guizhou Province matched with leptospiral serogroup Icterohaemorrhagiae serovar Lai, and PFGE, MLVA, and MLST, as reliable molecular techniques for identifying and typing of Leptospira interrogans, would contribute to the active surveillance, outbreak investigation and source tracking for leptospirosis in Guizhou Province.</p>

Analysis of surveillance results of Brucellosis in human being in Guizhou province from 2005 to 2008 / 中国地方病学杂志

Objective By analyzing the surveillance result of Brucellosis in human being of Guizhou province from 2005 to 2008,to understand the current situation of relevant population with brucella infection,and then to provide the basis for the development of prevention and control measures.Methods According to the Brucella Disease Monitoring Standards (GB 16885-1997),in Guizhou province,Huaxi,Wudang,Xingyi,Dushan,Ceheng,Long Lane,Xifeng,Carey,Ziyun and so on other areas(city,county) were selected as monitoring points,and occupational groups of animal husbandry in agricultural areas,as well as farmers and students contacted with livestock were selected as monitoring subjects.Rose bengal plate agglutination test(RBPT) and tube agglutination test (SAT) were used to detect Brucellosis antibody.Results From 2005 to 2008,Brucellosis antibody detection rate was 0.63％(37/5904) in target groups of Guizhou province,specifically,the rates in Huaxi,Wudang,Xingyi and Ceheng counties(towns or districts) were 2.28％(19/832),0.16％(2/1274),1.84％(15/815) and 0.14％ (1/735),respectively; the rates in livestock workers,peasants and students contacted with livestock in rural areas were 1.29％ (36/2800),0.04％ ( 1/2814) and 0.00％ (0/290),respectively.In all antibody positive carriers,most were dairy cattle raisers which accounted for 83.78％ (31/37) in the total infected persons.Conclusions Dairy cattle and goat raisers in some counties(towns or districts) of Guizhou province have infected Brucellosis,and direct contacts with brucella-carrying cattle is the major route of Brucellosis transmission in human being.Strengthen livestock quarantine and dispose infected livestock timely are the key of Brucellosis control.

Analysis on nucleoprotein gene sequence of 25 rabies virus isolates in Guizhou Province, China / 病毒学报

To analyze 25 nucleoprotein gene (N gene) sequences of rabies viruses circulating in Guizhou province during 2005-2010, China, and to explore the epidemic characteristics and the probable mutant of rabies in Guizhou Province. Rabies virus RNA in human brain tissues, human saliva, and domestic dog brain tissues derived from different prefectures of Guizhou Province were detected with RT-nested PCR, and the amplified products were then sequenced. Bioinformatics software was used to determine the genetic characteristics of these rabies viruses. The sequences of N gene of 25 Guizhou provincial isolates were identical with homogeny between 97.5% - 99.3% and 98.4% - 99.8% at nucleotide and deduced amino acid level, respectively, while the identities between them and isolated strains from other province of China were 88% - 99.1% and 88% - 99.7%. There were several amino acid substitutions in the nucleoprotein of 25 Guizhou isolates compared with the known genotype 1 isolates. The analysis of phylogenetic tree of 25 Guizhou isolates was demonstrated to be genetically divided into two groups, indicating that the virus presented a unique characteristics in geographic distribution and in a time dependent-manner. And phylogenetic tree of 25 Guizhou isolates and 7 genotype 1 strains isolated from other Province of China was also divided into two groups, which were further composed of several subgroups, respectively. From these observations, the rabies viruses derived from Guizhou province were still genotype 1. These isolates of rabies virus were diverged from the strains isolated from other provinces in both gene sequences and deduced amino acid sequences, and these divergences were characterized in geographic distribution and in a time-dependent manner.

Study on the status of infection and distribution of rabies virus in China / 中华流行病学杂志

Objective To investigate the status of infection and distribution of rabies virus (RV) in different epidemic areas in China. Methods Brain specimens from animals and suspected patients were collected at the districts of high-, medium- and low incidence rates of human rabies and detected by both direct Immunofluorescence assay (DFA) and RT-PCR. Results 254 of 3007 specimens of dog brains showed RV positive by DFA (positive rate of 8.4% ). Among these 254 samples, 78 showed positive (positive rate of 30.7% ) by RT-PCR. 93 specimens from dogs and cats that had attacked human beings, 63 of them showed positive by DFA (positive rate of 67.7%) and all of them were also positive by RT-PCR. In addition, RV could also be detected in Apodemus agrarius,ferret badger, and suspected patients specimens from the districts under survey. There was no statistical difference between the infection rates of RV in different provinces and regions with different incidence of rabies. Conclusion There might be a relatively high infection rate of RV among the domestic dogs/cats in the endemic areas in China. Wild animals might have been infected with RV in the districts under survey.

Self-management behaviors among children after exposure to rabies in two severe rabies epidemic areas of China / 中华流行病学杂志

Objective To understand the situation of rabies exposure and self-management behaviors among primary school students from rabies epidemic areas in China. Methods This population-based investigation was conducted in Guizhou and Guangdong provinces which had been severe epidemic areas of rabies in China from January 2007 to May 2008. Primary schools from two prefectural, two county, four township and four village levels were selected in the 2 provinces.Students were sampled from each grade of the 12 schools to collect information on post-exposure prophylaxis. Results In the 2408 primary school students interviewed, 290 person/times exposure were found from 2007 to 2008. The self wound-treatment rates was 47.93%, with 16.55% of themwent to the clinic for care-seeking initiatively and 63.79% informed their parents or teachers. However 23.10% of the students did nothing after exposure. Students in Guangdong province had lower exposure rate and higher rate of good management behaviors than in Guizhou. No significant statistical difference was found between the self-management behaviors among male and female students or among different levels of primary schools. The proportion of disinfection on wounds with alcohol and seeking medical treatment in rabies clinic initiatively were both low in all grades of the students but the proportion of telling their parents or teachers about the exposure among children was high in all grades of students. Conclusion Some students after rabies exposure did not have any disposal in Guangdong and Guizhou provinces. Related education should be strengthened.

Survey and anslysis of infection rate of dog rabies in the regions with high incidence of human rabies / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the situation of dog rabies and analyze it's relationship with human rabies.</p><p><b>METHODS</b>In Guizhou, Guangxi and Hunan provinces which suffered from rabies most heavily, one or two cities were selected respectively from regions with high-, middle-, low-incidence rate of human rabies as investigation spots where Dogs' brain specimens were collected and detected with both direct immunofluorescence assay (IFA) and RT-PCR.</p><p><b>RESULTS</b>A total of 2887 specimens were collected and 66 of these were positive for IFA and RT-PCR. Therefore, the rate of positive specimens was 2.3%. However, there was not a close relationship in the incidence rate of dog rabies and human rabies.</p><p><b>CONCLUSION</b>Dog's infection situation of rabies contributed to the severe epidemic of human rabies.</p>

Characterization of rabies virus phosphoprotein in high prevalence provinces of China / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>Characterization of rabies virus phosphoprotein through analyzation of genetic variations about rabies virus phosphoproteins in high-incidence regions in China.</p><p><b>METHODS</b>The nucleotide sequence of the P gene of Guangxi, Guizhou and Hunan provinces positive sample's were sequenced, and the P region's similarity and phylogenetic analyses were completed by using softer wares.</p><p><b>RESULTS</b>The similarity of P region's nucleotide sequence is 82.1%-100%, while, the similarity of amino acid sequence is 87.5%-100%. A little variation in phosphoprotein cannot influence its biological functions.</p><p><b>CONCLUSION</b>All rabies viruses isolated from Guangxi, Guizhou and Hunan provinces belong to genotype 1 and share same phylogenesis and same genome characteristic; Virus distribution presents unique Characterization; Some virus isolates from Hunan province and Thailand may come from the same virus.</p>

An epidemiological study of rabies virus in domestic dogs, cats and wildlife and the immunogenicity study for rabies vaccines derived from different cell cultured virus strains / 病毒学报

For epidemiological investigation of the rabies virus carrier rates of domestic dogs, cats and wild animals like rodent animals and bats,three kinds of regions where rabies had higher incidence (Hunan and Guizhou Provinces), lower incidence (Jiangsu Province, Wuhan City) and provisionally rabies-free (Shenyang City) were selected. Then the antigenic types, the genovariation of the isolaled viruses and the currently vaccine matching of the virus strains were analyzed. The results showed that in China the principal host of rabies is dog,the total virus carrier rate of the captured dogs was 2.56%, and the highest positive isolation rate was 20.0% in some monitoring site. However,there was no evidence about the rabies virus carrier rate in rodent animals,bats or other wild animals. The rabies vaccines which prepared from aG and CTN strains have already been produced successfully in China. The research showed that the nucleotide sequences of the newly isolated viruses were more similar with the glycoprotein gene of CTN strain. In order to evaluate the safety and the efficacy of the vaccines currently used, two groups (50 people each) were injected with vaccine of aG strain and CTN strain respectively in five surveillance points. The neutralizing antibody tested were 0.49 IU/mL-0.52 IU/mL and 6.7 IU/mL-7.53 IU/mL after the 7 and the 14 days of vaccine injection respectively. In addition, the rates of antibody positive seroconversion were 45.1%-47.9% and 100% respectively, and there was no moderate or severe adverse reactions observed. These data showed the vaccines have satisfactory effect on safety and protection.

Analysis on the factors related to rabies epidemic in China, in 2005 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To analyse the related epidemic factors of rabies and to provide basic evidence for developing rabies control and prevention programs in China.</p><p><b>METHODS</b>Possible factors that causing rabies epidemics in the southern part of China were obtained through collecting both epidemic and surveillance data of rabies in 2005, and to analyse every factor by software of Excel 2002.</p><p><b>RESULTS</b>The number of rabies cases was 2548 in 2005. Among 885 cases being investigated, 60.56%, 49.04%, 96.16% had not had any chance to receive treatment, vaccine or immunoglobulin. Among the exposed persons, 89.95% received treatment on wounds and 94.93% were immunized, and 8.56% received immunoglobulin. 94.86% of them accomplished the full rabies post-exposure prophylaxis course, but 8.56% of them did not accomplish it. 88.50% of the cases and 92% of the persons under exposure were bitten by dogs. The density of dogs was 3.20-13.37 per 100 persons. The vaccination coverage rates among dogs were 5.31% -75.11% with a positive rate of 2.93 % -6.40%.</p><p><b>CONCLUSION</b>Factors as: low rate of post-exposure prophylaxis and failed to have finished the necessary post-exposure treatment (PET) of the cases, nonstandard PET in hospital or local clinic, low rabies vaccination coverage and high infectivity of rabies virus in animal host (mainly for dog) might be responsible for rabies epidemics in China, in 2005.</p>

Surveillance on hemorrhagic fever with renal syndrome in Guizhou during 1984-2000 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the relations between different areas on hemorrhagic fever with renal syndrome (HFRS) in Guizhou.</p><p><b>METHODS</b>Various forms of infectious areas were surveyed continuously through epidemiologic surveillance system.</p><p><b>RESULTS</b>In fixed areas under surveillance system, the mean positive rate of HFRSV among Apodemus agrarius was 3.39%, comparing with Rattus norvegicus 1.61% in Apodemus infectious areas of Zunyi county, 3.19% in Rattus norvegicus, but no HFRSV of Apodemus agrarius was identified in Rattus infectious area of Shiqian county. Both Apodemus and Rattus infectious areas were relatively stabilized. In both banks of Luowang river, Kaiyang county, which had been identified as areas of infections for Apodemus in the eastern part, Rattus infectious area in the west, slow change was noticed. In 1983 - 1984 was not found in Apodemus agrarius HFRSV, however the infectious rate of HFRSV in Apodemus agrarius was 13.85% (Ag 1/65, Ab 8/65) in the western part of the province in 1995 - 1998.</p><p><b>CONCLUSION</b>Both Apodemus and Rattus infectious areas were stabilized but changed slowly. Mixed type and the result of mutual penetration were noticed.</p>

Study on ribotyping of Lyme borreliosis spirochete in Guizhou province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To define the main genotypes in Guizhou agricultural areas by molecular epidemiologic investigation of 21 Borrelia burgdorferi sensu lato of Lyme disease spirochetes and to provide the scientific bases for formulating a preventive policy.</p><p><b>METHODS</b>Polymerase chain reaction (PCR) technique was used to amplify the 23S(rrl)-5S(rrf) intergenic spacer, and amplified products were analyzed by restriction fragment length polymorphism (RFLP) and nucleotide sequencing.</p><p><b>RESULTS</b>There were two genospecies in the strains: 20 strains belong to Borrelia valaisiana, 1 strain is Borelia sp.</p><p><b>CONCLUSION</b>Borrelia valaisiana was the main genotype in Guizhou agricultural areas. The harmness of B. valaisiana to human being has been confirmed. In order to efficiently prevent the harmness of agent to the people in Guizhou agriculture areas, we should study the risk further.</p>