Analysis of epidemiological characteristics of severe fever with thrombocytopenia syndrome in Yiyuan of Shandong Province，from 2014 to 2019 / 上海预防医学

ObjectiveTo understand the epidemiological characteristics of severe fever with thrombocytopenia syndrome （SFTS） in Yiyuan County， and provide scientific evidence for prevention and control strategies. MethodsDescriptive epidemiological methods were used to analyze the incidence of SFTS in Yiyuan County during 2014—2019. ResultsA total of 130 SFTS cases were documented in Yiyuan County during 2014—2019， of which four were death cases. The annual incidence was determined to be 3.79/105 and the mortality was 3.08%， showing an upward trend in the incidence （ χ T r e n d 2 =9.06， P=0.003）. Majority of the cases occurred between May and August （88.46%）， were more than 50 years old （81.54%）， and farmers （94.62%）. The median duration of time from onset to diagnosis was five days. ConclusionSFTS was widely distributed in Yiyuan County with seasonal pattern. Middle aged and elderly farmers were mainly susceptible. It warrants strengthening prevention and control of SFTS and health education in elderly.

Analysis of epidemiological characteristics of severe fever with thrombocytopenia syndrome in Yiyuan of Shandong Province，from 2014 to 2019 / 上海预防医学

ObjectiveTo understand the epidemiological characteristics of severe fever with thrombocytopenia syndrome （SFTS） in Yiyuan County， and provide scientific evidence for prevention and control strategies. MethodsDescriptive epidemiological methods were used to analyze the incidence of SFTS in Yiyuan County during 2014—2019. ResultsA total of 130 SFTS cases were documented in Yiyuan County during 2014—2019， of which four were death cases. The annual incidence was determined to be 3.79/105 and the mortality was 3.08%， showing an upward trend in the incidence （ χ T r e n d 2 =9.06， P=0.003）. Majority of the cases occurred between May and August （88.46%）， were more than 50 years old （81.54%）， and farmers （94.62%）. The median duration of time from onset to diagnosis was five days. ConclusionSFTS was widely distributed in Yiyuan County with seasonal pattern. Middle aged and elderly farmers were mainly susceptible. It warrants strengthening prevention and control of SFTS and health education in elderly.

Emerging New Phylogenetic Groups of Rabies Virus in Chinese Ferret Badgers / 生物医学与环境科学（英文）

Chinese ferret badger (FB)-transmitted rabies is a serious threat to public health in southeast China. Although mostly associated with dogs, the rabies virus (RABV) presents genetic diversity and has a significantly wide host range in China. Instead of the dog- and wildlife-associated China II lineage in the past decades, the China I lineage has become the main epidemic group hosted and transmitted by dogs. In this study, four new lineages, including 43 RABVs from FBs, have been classified within the dog-dominated China I lineage since 2014. FB RABVs have been previously categorized in the China II lineage. Moreover, FB-hosted viruses seem to have become the main independent FB-associated clade in the phylogenetic tree. This claim suggests that the increasing genetic diversity of RABVs in FBs is a result of the selective pressure from coexisting dog rabies. FB transmission has become complicated and serious with the coexistence of dog rabies. Therefore, apart from targeting FB rabies, priority should be provided by the appropriate state agencies to perform mass immunization of dog against rabies.

Possible Transmission of Irkut Virus from Dogs to Humans / 生物医学与环境科学（英文）

Lyssaviruses, including Rabies virus, Duvenhage virus, European bat lyssavirus 1, European bat lyssavirus 2, Australian bat lyssavirus, and Irkut virus (IRKV), have caused human fatalities, but infection of IRKV in dogs has not been previously reported. In China, a dead dog that previously bit a human was determined to be infected with IRKV. Pathogenicity tests revealed that IRKVs can cause rabies-like disease in dogs and cats after laboratory infection. The close relationship between humans and pets, such as dogs and cats, may generate a new spillover-spreading route for IRKV infection. Therefore, additional attention should be paid to trans-species infection of IRKV between bats and dogs or dogs and humans through investigation of the prevalence and circulation patterns of IRKV in China.

Dog-transmitted Rabies in Beijing, China / 生物医学与环境科学（英文）

Rabies remains a continuous threat to public health in Beijing. In this study, a total of 224 brain tissues were collected from suspected infected stray dogs within Beijing between January 2015 and December 2016. Among them, total of 67 samples were diagnosed positive for rabies. In the phylogenetic analysis, rabies in Beijing is currently a relatively independent public health issue originating from local rabid dogs apart from the imported cases from elsewhere in the country. Because vaccination of unregistered dogs against rabies is still neglected in Beijing and other regions of China, national and local authorities should play central roles in all related aspects, such as development of policies, engagement of stakeholders for public and professional education, entire vaccination process, and animal management.

Construction and immunogenicity analysis of recombinant replication-defective human adenovirus type 5 bearing the porcine circovirus type 2 Cap protein gene / 病毒学报

To construct a recombinant replication-defective human adenovirus type 5 expressing Cap protein of PCV2 and test the immunological efficacy in mice. In this study, the recombinant replication-defective human adenovirus type 5, named as rAd5-Cap (wt-rAd5), was constructed through homologous recombination internally in the HEK293AD cells after co-transfection of the Pac I-linearized backbone plasmid and the shuttle plasmid pacAd5CMV-Cap containing the open reading frame (ORF2) of the porcine circovirus type 2 (PCV2) cap protein or pacAd5CMV without inserted fragment. Furthermore, the rAd5-Cap could induce the expression of PCV2 cap protein in the HEK293AD cells with high efficacy evaluated by the RT-PCR and indirect immunofluorescence assay (IFA). The virus titer of rAd5-Cap could reach up to 10(8.5) TCID50/mL similarly to that of wt-rAd5, indicating that there was little affect on the virus proliferation after the insertion of PCV2 cap protein gene. The humeral immune responses could be activated and detected 14 days after the inoculation of the mice with 10(7) TCID50 rAd5-Cap intramuscularly, and constantly in crease in another 14 days. These molecular biological and animal experiments results demonstrated that the PCV2 cap protein could be efficiently expressed by the recombinant adenovirus rAd5-Cap in eukaryotic cells and induce robust immune responses in mice, which laid a good foundation for the development of new type vaccine against porcine circovirus.

Immune efficacy of rabies virus glycoprotein expressed by baculovirus vector / 病毒学报

To construct a recombinant baculovirus expressing glycoprotein (GP) of RV SRV9 strain and test the immunological efficacy in mice, open reading frame of rabies virus GP gene of SRV9 strain was cloned into the shuttle vector Bacmid to construct the recombinant shuttle plasmid Bacmid-G and transfection was performed into S f9 cells with the recombinant shuttle plasmid. CPE appeared in cell cultures was identified by electronmicroscopy. Western-blot, IFA and immunity tests in mice were performed to identify the immunoreactivity and immunogenicity of the expression products. Our results showed a recombinant baculovirus expressing GP protein of rabies virus SRV9 was obtained. The expression products possessed a favorable immunogenicity and fall immunized mice could develop 100% protective level of anti-rabies neutralizing antibody. In conclusion, The SRV9 glycoprotein expressed by the recombinant baculovirus in this study had good immunogenicity and could induce anti-rabies neutralizing antibody, which laid the foundation of further development of rabies subunit vaccine.

Generation and preliminary immunological efficacy of a recombinant human adenovirus-rabies virus glycoprotein / 病毒学报

To construct a recombinant human adenovirus type 5 expressing glycoprotein (GP) of attenuated rabies virus SRV9 and testing immunological efficacy on the immunized mice. Open reading frame of rabies virus GP gene of SRV9 strain was cloned into the shuttle vector of adenovirus expression system in multiple cloning sites to construct the recombinant shuttle plasmid pacAd5 CMV-Gs9, cotransfection was performed into 293AD cells mediated by FuGENE Transfection Reagent with linearized backbone plasmid and recombinant shuttle plasmid, cell cultures were collected after CPE appearance and were identified by PCR and electronmicroscopy, virus titer was measured in 293AD cells. Kunming mice were intraperitoneally injected with 10(6) TCID50 adenovirus, blood for serum preparation was collected through caudal vein pre-immune and post-immune and tested for VNA appearance by fluorescent antibody virus neutralization test (FAVN) detection. Recombinant shuttle plasmid pacAd5 CMV-Gs9 was constructed correctly. A recombinant human adenovirus type 5 was obtained expressing GP protein of rabies virus SRV9. The virus titer reached 10(6) CFU/mL at the least. All mice developed a certain amount of the anti-rabies neutralizing antibody 14 days after intraperitoneal inoculation, while the effective protection rates were 90%. In conclusion, Recombinant adenovirus expressing the rabies virus GP was constructed successfully and a certain amount of neutralizing antibodies were induced in mice, which laid the material foundation for further development of new rabies vaccine.

Construction of eukaryotic expression vector of general type in reverse genetic systems of non-segmented negative strand RNA virus / 病毒学报

To construct eukaryotic expression vector of general type in reverse genetics systems of non-segmented negative strand RNA viruses, the multiple cloning site of the plasmid pVAX1 was replaced with HamRz cDNA sequence, a 9 sites linker and HdvRz cDNA sequence through the sequential addition of three adapters, the insertion of which could generate the correct 3' and 5' terminal sequences of the primary viral genomic RNA transcript and facilitate the assembly of the complete viral cDNA sequence. The sequences of the three adaptors were correct after identifying by restriction endonuclease digestions and sequencing. The constructed eukaryotic expression vector could not only be used to assemble viral genome, but also provide the basis for establishing the reverse genetic system rapidly.

Expression and characterization of rabies virus nucleoprotein in baculovirus / 病毒学报

To construct a recombinant expression plasmid Bacmid-N containing the N gene of Rabies Virus, the N gene of RV CVS-11 strain was cloned into the baculovirus shuttle vector (Bacmid). Recombinant Baculovirus AcMNPV-N (P1 Viral stock) was obtained by transfecting the Bacmid-N into the insect cell line of Sf9. The expressed nucleoprotein was identified and analysised by ELISA, FA, SDS-PAGE and Western blot assays. The results showed that the NP protein was expressed intracellularly and had a good antigenicity, which would be potentially used for further study on the diagnostic reagent of rabies virus detection.

Preparation and characterization of monoclonal antibodies to rabies virus CVS-11 strain / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To get the high specific and sensitive mononclonal antibodies against RV.</p><p><b>METHODS</b>The myeloma cell line SP2/0 fused with the spleen cell of 6 - 8 weeks old BALB/c mice immunized with the CVS-11 virus antigen. The hybridized fusing cells were chosen by indirect ELISA detection and the positive hybridizing cells were amplified through mouse abdomen injection and the mouse McAbs ascites was purified by Protein A Sepharose 4 Fast Flow (Pharmacia Company). The specificity and sensitivity of the McAbs was identified by indirect ELISA and indirect DFA test.</p><p><b>RESULTS</b>The cell fusion rate reachs 100% and the indirect ELISA results showed that the McAbs ascites titer were 1 x 10(4), 1 x 10(5), 1 x 10(4) and 1 x 10(5); The immunoglobulin G type McAbs show no cross reaction with other related viruses.</p><p><b>CONCLUSION</b>The high specific and sensitive mononclonal antibodies of RV can be used for rapid RV diagnosis.</p>

Construction of a transfer vector based on canine adenovirus type-2 / 生物工程学报

Canine adenovirus type 2 (CAV-2) has been proposed as a vector for recombinant vaccine. Alternatively, it may be an attractive tool for gene transfer due to lack of pre-existing immunity in humans. In this study, a transfer vector based on CAV-2, in which the 1381bp fragment of the E3 region was deleted, and a linker containing the Not I, Cla I, Fse I restriction enzyme sites were cloned into the deleted region. The recombinant CAV-2 genome was released from the plasmids enzyme digestion and transfected into MDCK cells by lipofectamine to obtain the recombinant virus. No significant difference in morphology, hemagglutination and replication between the recombinant and the wide type CAV-2 was found. These results indicated that this recombinant virus CAV-2-deltaE3 (NF) may be an efficient vector for gene transfer and the capacity of the vector for inserted foreign gene was up to 3.3kb.