Animals ; China ; Hantavirus Infections ; veterinary ; Rodent Diseases ; virology

OBJECTIVETo investigate the Hantavirus infection and their genotype in rodents in Huludao.

METHODSRodents were collected from the main epidemic areas to detect antigen of Hantavirus in rat lungs by indirect immunofluorescence assay. Antigen-positive samples were inoculated onto cultures of confluent Vero E6 cells for the isolation of virus. The genotypes of viruses in all antigen-positive samples were identified by reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS200 rats were collected in the main epidemic areas, and 11 Hantavirus-positive samples were tested. The positive rate of Hantavirus in rats was 5.5%. Three strains of Hantavirus were isolated in Vero E6 cell culture. Data from the phylogenetic trees constructed by partial S segment (620-999 nt) or partial G1 segment (180-580 nt) showed that the three isolates carried by rats from Huludao were all genetic subtype SEOV 3. Furthermore, the phylogenetic tree constructed by partial G2 segment (2003-2302 nt) divided SEOV strains into 7 genetic subtypes, and the three isolates were having a closer evolutionary relationship with isolates CP211, ch302 and dc501 from Beijing, and the isolates SD10 and SD227 form Shandong.

CONCLUSIONData indicated that the rate of carrying virus was high and the main genetic subtype of Hantavirus was S3 of Seoul virus in Huludao area.

Animals ; Carrier State ; China ; Hantavirus ; classification ; genetics ; isolation & purification ; Hantavirus Infections ; veterinary ; Lung ; virology ; Phylogeny ; Rats ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVEFor clarifying the situation of the natural infection of rodents having hemorrhagic fever with renal syndrome (HFRS) virus and to type Hantavirus (HV) using molecular technique in Shenzhen city in 2005, and offering guidance for prevention and control of HFRS.

METHODSData on the host animals was collected from the city of Shenzhen. ELISA and indirect immunofluorscent antibody(IFA) test were applied to the specific antibodies against HV in the sera of captured rats. Direct immunofluorscece assay was adopted to determine HFRS antigens and the lung tissues of the HV infected rats were inoculated into Meriones unguiculata to isolate HV. The whole viral RNA was extracted from the lung tissues of the HV infected rats and amplified the partial M fragments with RT-nested-PCR, using the HV genotype specific primers. The amplified genes were then sequenced, and subjected to genotyping and homology analysis.

RESULTS472 rodents were captured from Shenzhen in 2005. Surveillance on rats demonstrated 9.96% rats carrying HV (with a density of 8.25%) and the main host was Rattus norvegicus. In the blood samples of rats, anti-HV IgG antibodies were detectable in 56 cases by IFA, and proved to be positive in 76 cases by ELISA. We successfully isolated a HV strain designated as SZ2083 from Rattus norvegicus for the first time in Shenzhen and was identified to SEO type by RT-nested-PCR. Compared with the coding region of the M gene of HV L99 virus strain, the homologies of nucleotide among them were 97%, but the homology was 76% of the SZ2083 with HTN 76-118 virus strain.

CONCLUSIONResults showed the existence of natural epidemic areas of HFRS in Shenzhen city. Based on the results of sequencing, it is possible that the Seoul strain of HV might be the predominant serotype of virus harbored.

Animals ; China ; epidemiology ; Cities ; Data Collection ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique, Indirect ; Genotype ; Hantavirus ; classification ; genetics ; isolation & purification ; Hantavirus Infections ; epidemiology ; veterinary ; Rats ; virology ; Rodentia ; virology

OBJECTIVEIn order to investigate Hantavirus (HV) infection of captured rodents and to understand the genotypes and the molecular characteristic of Hantaviruses in Shenzhen.

METHODSThe captured rodents were classified and the density of distribution was calculated. A total of 472 animals were captured, among which Rattus norvegicus was the dominant group. The total viral RNA was extracted from the lung tissues positive with HV antigens by immunofluorescent assay and gene sequence of M fragment was amplified with RT-nested-PCR by using the Hantavirus genotype specific primers. The amplified genes were then sequenced, and subjected to genotyping and homology analysis.

RESULTSThe results of genotype analysis showed that the Hantaviruses taken from twenty-one lung specimens in Rattus norvegicus in Shenzhen city belonged to the Hantavirus type II (SEOV). Results in homology analysis suggested that the homology among twenty-one samples should be rather high with 95.4% of nucleotide sequence identity and they belonged to the same subtype. Phylogenetic tree analysis showed that they were branched into at least six different lineages, and were highly homologized with SZ2083. We also found that these virus strains had not shown more highly homology of nucleotide sequence in nearest district, whereas revealed consistency in farther district.

CONCLUSIONThe major hosts of Hantaviruses in Shenzhen city were Rattus norvegicus and the epidemic strains were genotyped as SEO-type. Nucleotide sequence and deduced amino acid sequence from different rodents were highly homologous, while nucleotide mutation had also been observed. Further studies are required to explore the possible viruses' sequence mutation.

Animals ; China ; epidemiology ; DNA Primers ; DNA, Viral ; Genotype ; Hantavirus ; classification ; genetics ; Hantavirus Infections ; epidemiology ; veterinary ; virology ; Polymerase Chain Reaction ; RNA, Viral ; Rats ; Rodent Diseases ; epidemiology ; virology ; Sequence Homology

Objective: To study the molecular epidemiological characteristics and genotypes of hantavirus carried by rodents in Shenzhen. Methods: Rodents were captured, and their lung samples were collected and grinded for RNA extraction. The hantavirus positive samples were classified by real-time fluorescence PCR. Rat lung nucleic acid samples were selected to amplify the nucleotide sequences of partial M fragments (G2 segment) and S fragments by reverse transcription-nested polymerase chain reaction (RT-nested PCR). The PCR products were then sequenced and homology and phylogenetic tree analyses were conducted. Results: A total of 200 rodents were captured, including 189 Rattus norvegicus, 9 Rattus flavipectus and 2 Mus musculus. The positive rate of hantavirus was 21.0% (42/200), all of the isolates were seoul virus (SEOV) strains. The positive rate of hantavirus in Bao'an district was highest (45.7%), and the difference in detection rate among districts were significant (χ²=25.60,P<0.05). A total of 25 G2 segment sequences and S fragment sequences of SEOV were obtained by virus gene sequencing, and their nucleotide homology was 95.3%-100.0% and 97.6%-100.0%, respectively. Compared with other reference sequences of S2 subtype, the nucleotide homology between the sample sequence and the reference sequence from Guangzhou was high. Analysis on nucleotide homology and phylogenetic tree showed that hantavirus carried by the rodents captured in Shenzhen belonged to SEOV S2 subtype. Analysis on amino acid variation sites revealed that there was a variation in the nucleocapsid protein encoded by S gene from Alanine to Threonine at the 973 position of BA-111. Conclusion: Hantavirus carried by rodents in Shenzhen belongs to S2 subtype of Seoul virus, which have little variation compared with the hantavirus strains obtained in other years in Shenzhen and surrounding provinces.
Mice ; Rats ; Animals ; Orthohantavirus/genetics* ; Rodentia ; Phylogeny ; Hantavirus Infections/veterinary* ; Communicable Diseases ; Nucleotides ; Real-Time Polymerase Chain Reaction

OBJECTIVETo further understand the association of hantavirus (HV) harbored and transmitted in wild brown rats.

METHODSRattus norvegicus (n = 570) were trapped in 10 sites in Beijing. RT-PCR was used to test rodent lung samples for hantavirus infection. Unconditional multivariate logistic regression analysis was performed, with PCR positive as the dependent variable and the characteristics of Rattus norvegicus population as independent variables.

RESULTSThe overall HV prevalence in Rattus norvegicus was 9.1% (52/570). Significant association between HV infection in Rattus norvegicus and some biological characteristics of host population was observed. Adult Rattus norvegicus had a higher HV prevalence than juveniles. Males in the reproduction periods and rats with wounds were more likely to be infected with HV than others.

CONCLUSIONIt was further confirmed that there existed parallel transmission of HV in Rattus norvegicus hosts. Aggression might be the primary mode of HV transmission among male Rattus norvegicus.

Aggression ; Animals ; Animals, Wild ; injuries ; virology ; China ; epidemiology ; Female ; Hantavirus ; isolation & purification ; Hantavirus Infections ; epidemiology ; transmission ; veterinary ; virology ; Logistic Models ; Lung ; virology ; Male ; Prevalence ; Rats ; injuries ; virology ; Reproduction ; Reverse Transcriptase Polymerase Chain Reaction ; Risk Factors ; Rodent Diseases ; epidemiology ; transmission

In order to study the molecular characterization of the hantavirus isolated from Apodemus peninsulae in Heilongjiang Province, the S gene of a new strain NA33 was amplified, sequenced and analyzed. The results showed that the complete nucleotide sequence of the S gene of NA33 strain was composed of 1 693 nucleotides with TA-rich. The S gene contained one ORF, starting at position 37 and ending at position 1 326, encoding the N protein of 429 amino acid residues, and in line with HTN-based coding. Sequence comparison of the S genes between NA33 and reference hantavirus strains showed that NA33 was more homologous to Amur-like viruses than to the Hantaan (HTN) viruses or the other hantaviruses. Phylogenetic analysis of the amino acid sequence of N proteins showed that NA33 was clustered into the group of Amur-like viruses and was more similar to Far East Russia and Jilin strains isolated from Apodemus peninsulae. The phylogenetic tree indicated a certain degree of host-dependent characteristics and geographical aggregation characteristics of hantanviruses. Furthermore, the amino acid sequence of N protein of NA33 had the conserved amino acid sites of Amur-like viruses. In conclusion, Apodemus peninsulae carried Amur-like viruses in Heilongjiang province and was an important infectious source of hemorrhagic fever with renal syndrome (HFRS).
Animals ; China ; Hantavirus ; chemistry ; classification ; genetics ; isolation & purification ; Hantavirus Infections ; veterinary ; virology ; Humans ; Molecular Sequence Data ; Murinae ; virology ; Phylogeny ; Rodent Diseases ; virology ; Sequence Homology, Amino Acid ; Viral Envelope Proteins ; chemistry ; genetics

OBJECTIVETo investigate the impact of impoundment and active public health interventions on rodent populations and rodent-borne diseases in the Three Gorges reservoir region from 1997 to 2012.

METHODSSurveillance data from 1997 to 2012 were extracted from the Public Health Surveillance System of The Three Gorges established in 1997. Temporal changes in the incidences of hemorrhagic fever with renal syndrome (HFRS) and leptospirosis, rodent density, pathogen-carrying rates, and their correlations were analyzed.

RESULTSThe average indoor and outdoor rodent densities decreased overall from 1997 to 2012. The average densities decreased by 47.72% (from 4.38% to 2.29%) and 39.68% (from 4.41% to 2.66%), respectively, after impoundment (2003-2012) compared with before impoundment (1997-2002). The average annual incidence rates of HFRS and leptospirosis were 0.29/100,000 and 0.52/100,000, respectively, and decreased by 85.74% (from 0.68/100,000 to 0.10/100,000) and 95.73% (from 1.47/100,000 to 0.065/100,000), respectively, after impoundment compared with before impoundment. Incidences of HFRS and leptospirosis appear to be positively correlated with rodent density in the reservoir area.

CONCLUSIONThis study demonstrated that rodent density and incidences of rodent-borne diseases decreased and were maintained at low levels during construction of the Three Gorges dam. Measures that reduce rodent population densities could be effective in controlling rodent-borne diseases during large-scale hydraulic engineering construction.

Animal Distribution ; Animals ; China ; epidemiology ; Disease Reservoirs ; Hantavirus Infections ; epidemiology ; veterinary ; Leptospirosis ; epidemiology ; virology ; Population Density ; Rodent Diseases ; epidemiology ; microbiology ; virology ; Rodentia ; Seasons ; Time Factors ; Water Supply ; Zoonoses

OBJECTIVETo investigate hantanvirus infection of captured rodents in Haidian district and Changping district of Beijing and to type hantavirus using molecular technique.

METHODSThe captured mice were classified and the density of distribution was calculated. Reverse transcription-polymerase chain reaction (RT-PCR) technique was used to amplify the partial M fragnments of hantaviruse. Several representative positive samples were sequenced and analysed by ClustalX (5.0) and DNAClub software.

RESULTSA total of 414 animals were captured, among which Battus norvegicus was the dominant group. In Haidian district, the median infection rates with hantavirus were 13.14% in Battus norvegicus and 0 in Mus musculus Linnaeus. In Changping district, the average infection rates were 17.46% in Battus norvegicus and 3.57% in Mus musculus Linnaeus. Nucleotide sequences analysis showed that the virus detected all belonged to SEO-type. They clustered with Z37 virus and could be branched into 2 different subclades.

CONCLUSIONThe major hosts of hantavirus in Haidian and Changping district were Battus norvegicus and the epidemic strains in the two districts of Beijing were genotyped as SEO-type. Nucleotide sequence and deduced amino acid sequence from different rodents were highly homologous, while nucleotide mutation had also been observed. Further studies are required to explore the possible virus sequence mutation.

Animals ; China ; epidemiology ; DNA, Viral ; genetics ; Disease Reservoirs ; Fluorescent Antibody Technique ; Hantavirus ; classification ; genetics ; isolation & purification ; Hantavirus Infections ; epidemiology ; veterinary ; virology ; Hemorrhagic Fever with Renal Syndrome ; epidemiology ; veterinary ; virology ; Mice ; Molecular Epidemiology ; Phylogeny ; Rats ; Reverse Transcriptase Polymerase Chain Reaction ; Rodent Diseases ; epidemiology ; virology

To gain more insights into epidemiologic characteristics and genotype of hantavirus in Apodemus agrarius in Changbai Area. Complete hantavirus S segment sequences were amplified by RT-PCR and sequenced. The phylogenetic trees were constructed for analysis of genetic characters of hantavirus. A total of 58 Apodemus agrarius were trapped in the epidemic areas, and complete hantavirus S segment sequences were obtained from 4 lung samples of these rodents (6. 90%0). Phylogenetic analysis of the four S segment sequences indicated that all viruses isolated from Apodemu sagrarius were closely related to genotype 6 of Hantaan virus (95. 8%-96. 3%, nucleotide identity; 98. 6%-99. 5%, amino acid identity), all of them had a specific S387 different from other genotypes of Hantaan virus.
Animals ; Base Sequence ; China ; epidemiology ; DNA, Complementary ; chemistry ; genetics ; Disease Reservoirs ; virology ; Genotype ; Hantavirus ; classification ; genetics ; isolation & purification ; Hantavirus Infections ; epidemiology ; veterinary ; virology ; Lung ; virology ; Murinae ; virology ; Phylogeny ; RNA, Viral ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Rodent Diseases ; virology ; Sequence Analysis, DNA ; Viral Proteins ; genetics