Objective To investigate a cluster epidemic of severe fever with thrombocytopenia syndrome (SFTS) in a county in western Hubei Province, China, so as to provide a basis for formulating prevention and control measures for SFTS. Methods Descriptive epidemiological methods were used to analyze the epidemiological characteristics of the epidemic combined with clinical and laboratory tests, and Fisher’s exact probability method was applied to compare differences in rates of first-episode cases, with a focus on the risk factors for possible transmission. Results There was 1 index case and 4 subsequent cases, with 2 males and 3 females and ages ranging from 54 to 86 years (median: 64 years). The latency period of subsequent cases was 5 to 13 days,with a mean latency period of 7.75 days. Four of the 7 close contacts who swabbed the body of the index case (exposed to the blood) developed the disease,with a significant difference in the prevalence rate between people with different ways of exposure ( P=0.003). Conclusions This is the first cluster epidemic of SFTS that is transmissible from human to human in the area. Relevant regulatory authorities should disseminate the knowledge of prevention and control of SFTS among the public and strengthen SFTS diagnosis and treatment training among the medical staff. Thus,disease transmission can be effectively controlled and the case fatality rate can be reduced.

Objective To understand the genetic type and characteristics of Hantavirus carried by Rattus norvegicus in Qinhuangdao port. Methods Real-time PCR and sequencing technology were applied to detect the nucleic acid of Hantavirus. And the homologous and phylogenetic analysis of positive sequence were also accomplished. Results One of the R. norvegicus showed positive result for Hantavirus. Homogeneous analysis demonstrated that the nucleic acid sequence of Hantavirus S gene was high identity with Seoul(SEO)virus from both home and abroad. Phylogenetic analysis showed that Qinhuangdao Hantavirus was clustering together with S3 sub- genotype of Seoul(SEO)virus, and was most closely related to the isolate from Liaoning province. Conclusion The genotype of hantavirus carried by R. norvegicus in Qinhuangdao is SEO virus and the sub-genotype is S3 which is consistent with the popular type of hantavirus in Hebei province.

Objective To investigate the density and population distribution of small mammals and provide the scientific basis for the small mammal control in the new tourist area of Shenzhen city. Methods The cage trapping method was used to monitor small mammals in Dapeng district from March 2016 to February 2017. The small mammal density and composition ratio were calculated, and the enumeration data were analyzed by chi-square test. Results A total of 559 small mammals were caught, with Suncus murinus being the predominant species accounting for 48.30%, followed by Rattus norvegicus accounting for 25.22%. The average density of small mammals was 7.25%, and the seasonal fluctuation was obvious(1.72%-11.93%), with the peak period from August to October. The small mammal density varied with different habitats, the highest density(11.35%)was in the old houses. Conclusion The small mammal density in the new tourist area was relatively high. So, it should be strengthened to prevent and control the small mammals. Suncus murinus, R. norvegicus, and R. tanezumi are the main vectors of concern.

Objective To determine the complete genomic sequences of 3 Dengue 2 virus (DEN-2) strains isolated in Guangdong province, China and to investigate their genotypes and sources. Methods The complete genomic sequences of 3 DEN-2 strains (GD09/93, GD05/98, and GD19/2001) from Guangdong province were established by RT-PCR amplification. The phylogenetic tree of DEN-2 was constructed by Kimura method. Results The complete genomic sequences of 3 DEN-2 strains were 10 723 nucleotides (nt) in length and contained a single long open reading frame (ORF) of 10 173 nucleotides (97-10 269 nt), encoding 3391 amino acids. The ORF encoded structural and non-structural proteins, flanked by 5' and 3' non-coding regions. Comparing GD05/98 with GD09/93, GD05/98 with GD19/2001, and GD09/93 with GD19/2001, the nucleotide sequence homologies were 93.3%, 92.4%, and 97.6%, respectively, and the deduced amino acid sequence homologies were 96.7%, 96.5%, and 98.5%, respectively. Conclusion The DEN-2 strains are pathogenic in suckling mice. Compared with DEN-2-04 strain (nonpathogenic in suckling mice), there are 18 amino acid substitutions that confer changes in charge or polarity. The charge changes at PrM-134, NS2A-153, and NS4B-102 have a relatively strong impact on the antigenicity. GD05/98 strain falls within the groupⅡ comprising Thailand strains, while GD09/93 and GD19/2001 strains fall within the group Ⅳ comprising strains from Indonesia, Australian and Taiwan. There are different DEN genotypes in China, and one genotype of DEN-2 may be transmitted in different periods.

Objective To determine the population dynamics of mosquitoes and midges before and after sunset. Methods Net traps were set along certain locations at varying heights to capture the insects before and after sunset. Results Most of the captures were midges, amounting to 1039 of 7 genera, dominated by the genus Culicoides. The collected mosquitoes were of 2 species under 2 genera, totaling 53. The activity peak of the insects was approximately 1 hour after sunset. Conclusion The species composition and dynamics of mosquitoes and midges around the residential areas of Weng’ang village before and after sunset were generally clarified.

Objective This study aims to evaluate the risk for the introduction of African swine fever virus to China and to predict the potential distribution of the vectors, providing the basis for development of prevention and control strategies. Methods The adaptability analysis software, Climex, was employed to predict the potential distribution of soft ticks in China. Results The parameter setting was derived from the biological data of soft ticks and the default template parameters of Climex. The analysis revealed that the ecoclimatic indexes of soft ticks in such places as Yunnan, Guizhou, Eastern Sichuan, Chongqing, Southern Shaanxi, Hunan, Hubei, Northeastern Jiangxi, Anhui, Henan, Zhejiang, Jiangsu, Shandong and Hebei were greater than 20; these locations would be the highly suitable, potential habitats for soft ticks in China. Conclusion Some areas in China may be the natural foci of African swine fever, suggesting that the future monitoring and control should be focused on these regions.

Objective To establish a TaqMan probe?based fluorescence quantitative PCR assay for rapid detection of Dengue virus type 1 (DV1) to facilitate the clinical diagnosis. Methods A set of specific primers and TaqMan probes were designed for the RT?PCR according to the conservative gene sequences at the 5′-terminal non?coding regions of DV1. A total of 40 sera samples were collected from patients with dengue fever, and four serotypes of standard DV strains were used as the control. The specificity of the established TaqMan?based fluorescence quantitative PCR assay was determined using the RNA templates obtained through in vitro transcription in the RT?PCR of the standard strains as a positive control. The sensitivity of the assay was then compared with that of the DV?IgM/IgG?based ELISA by assessing the sera samples. Results The lowest detection limit of the established method was approximately 10 gene copies per reaction. As to the positive results among the sera samples collected from patients at different stages after onset, the RT?PCR had the highest positive detection rate during the first three days after onset (81.25%), while the ELISA?IgM had the highest positive detection rate from day 4 to day 6 after onset (85.00%). After 7 d, ELISA?IgG had the highest positive detection rate (75.00%). Conclusion The established RT?PCR assay was a highly sensitive, specific and reproducible approach for rapid detection of DV1, conducive to the early diagnosis of dengue fever.

Objective Find out the mosquito species and density in a military camp on Beijing suburb and search the new method of mosquito monitoring. Methods CO ₂ trapping lamp method, comparing with mosquito net trapping method at the same time. Results By CO2 trapping lamp method, total 676 mosquitoes were trapped, divided into 2 genus and 2 species. 95.71% of the total were Culex pipiens pallens, 4.29% were Aedes albopictus. Most of Culex pipiens pallens were trapped in work area and grove in the camp before midnight, and most of Aedes albopictus were trapped in life area and grove before dawn. By mosquito net trapping method, tatal 178 mosquitoes(within 2 h) were trapped, 83.70% of the total were Culex pipiens pallens,and 16.30% were Aedes albopictus. Conclusion Preliminary research on the mosquito species and density in a military camp on Beijing suburb showed that the CO₂ trapping lamp method is a reliable method of mosquito monitoring.

Objective To study the attractive efficacy of animals traps and animals blood to mosquitoes.Methods Animals blood were used to attract mosquitoes in laboratory and animals traps were used to attract mosquitoes in the field.Results In laboratory,the bred Culex pipiens pallens prefers to feed pig's blood,the bred Aedes albopictus and Ae.aegypti prefer to feed cattle's blood;and the most favorable blood feeding ratios of above three species are 51%,47% and 44% respectively.In the field,chicken attracted more wild Cx.pipiens pallens(1420) than rat,pigeon and sparrow,but rarely attracted Ae.albopictus(11).Conclusion The bred Cx.pipiens pallens prefers to feed pig's blood,the bred Ae.albopictus and Ae.aegypti prefer to feed cattle's blood;Chicken are more attractive to wild Cx.pipiens pallens.

Objective:To get the results of killing mice indoors and in the filelds with Chlorophacine. Methods:Using the soaked crushed corn as baits indoors and in the fields,there were two kinds of baits(0.012 75%,0.017%)at each site,200g/mu in the fields and 400g indoors compared with mussal made in Shanghai,150g/mu in the fields and 400g indoors. To test the effectiveness by putting clips at night and observing every 5-7 metres of eaqual rank.To observe the palatability of the different baits and the time of mice death. Results:The three ways got the same results both indoors and in the fields.Tested by χ ²,there were no obvious difference between the two sites ( P>0.05).The baits had good palatability to the mice,eaten over 90%,the mice began to die within two to three days after baiting and mosttly died four to seven days.Conclusion:Using Chlorophacine cost less and got good effects for killing mice over 86.5% and protecting plants more than 92%. Compared with mussal,there was no obvious differece on cost and effects,but Chlorophacine is cheaper,it is suittable to used in large areas instead of mussal or alternately.

Operational testing of electric traps and fan screen door and bead screen door was conducted in some dining halls in Shanghai. The traps in each facility were turned on during 1 wk, and then off during the next, for an 8-wk period, and the fan screen doors in each facility were turned on during 2 d, and then off during the next, for an 16-d period, and the bead screen doors in each facility were used during 1 d, and then unused during the next, for an 8-d period. Insect activity was monitored by counting number of specimens collected on flypaper, active insects were observed and patted with fly-pat in the room. More flies were caught on flypaper, collected by patted with fly-pat, and counted by eyesight during each time when traps and fan screen doors were turn on , and when bead screen doors were unused .The difference of data which were analyzed using χ ² contingency tables was significant. However, as shown by this study, electric traps and fan screen doors and bead screen doors show promise as pest-management devices in dining facilities, but other methods for flies control are necessary.

Rodents population in Xi an area belong to 24 species 16 genera and 4 families. Meriones meridianus Pall is the first time being reported in the area. The density of M. meridianus is a widely distribution at the southern part of Wei-river Taiyan area 21.69%, Xi an urban region is next, about 8.04%. It is the lower at the valley of Wei river plains, about 6.32%. The character of population in rodents, Cricetulus triton and Apodemus agrarius were predominant species at he valley's plains and Wei river Tai yan districts. But Apodemus agrarius is predominant species at urban of Xi an . The migration of rodents population in the area showed that R. flavipectus was obviously increasing for the past 10 years, and R. norvigicus was distinctly decreasing in the past 10 years. The relationship between rodents population and natural focus of endemic disease were discussed, and presented a programme about enhance the surveillance of diseases, promotion the work of of pest contorol to prevented rats-borne diseases to the local municipality.