Objective To investigate the epidemic situation of hemorrhagic fever with renal syndrome (HFRS) and the population distribution and virus-carrying status of host animals in Fujian province, China, from 2016 to 2018, and to provide a scientific basis for formulating feasible prevention and control measures for HFRS. Methods The descriptive epidemiological method was used to perform a statistical analysis of HFRS case data and host monitoring data in Fujian which were reported in Surveillance Information Reporting and Management System in 2016-2018. The ratio was compared by χ ² test. Results A total of 1 184 HFRS cases were reported in Fujian from 2016 to 2018, with a mean annual incidence rate of 1.02/100 000, and there were 2 deaths, resulting in a mortality rate of 0.17%. Most cases were observed in Nanping, Quanzhou, and Sanming cities. The cases were reported all year round, with the peaks in March to May and November to February, and the peak in spring was higher than that in winter. The high-risk population was young men, and the highest incidence rate was observed in men aged 65-70 years and women aged 60-65 years. A total of 12 854 effective cages were set in the surveillance sites of Fujian and 845 rodents were captured, with a mean density of rodents of 6.57%. A total of 845 lung samples were collected, among which 48 were positive, and the 3-year mean virus-carrying rat index was 0.06. Conclusion The incidence rate of HFRS in Fujian province tends to first decrease and then increase from 2016 to 2018, with high rodent density and virus-carrying rate, and there is still a risk of HFRS outbreak. It is recommended to adopt comprehensive prevention and control measures of vaccination and deratization.

Objective To evaluate the feasibility of applying DNA barcoding to identify common rodent species in Fujian province, China. Methods From 2017 to 2018, a total of 77 rodent specimens from 11 species and 5 genera were collected from some areas of Fujian province with cage traps in the daytime. Nucleic acid extraction and polymerase chain reaction (PCR), as well as gene sequencing, were performed to obtain their mitochondrial cytochrome c oxidase subunitⅠ(COⅠ) gene fragment sequences. Then the sequences were analyzed by homology alignment, genetic distance analysis, and phylogenetic tree construction to identify the species of the rodents. The identification results were compared with those of classical morphological identification. Results The specific COⅠgene fragments extracted from all the specimens could be amplified by PCR to produce bands, and their sequences all matched the corresponding known rodent species in GenBank database; the homology was 97.88% and above. The mean inter- and intra-specific genetic distances were 15.31% and 0.21%, respectively; the former was substantially bigger than the latter. Phylogenetic tree analysis showed that the same species of rodents were all clustered in the same evolutionary branch with high reliability. Among the 77 specimens, 3 had different identification results. After morphological re-identification, the results of field identification were found to be incorrect. Conclusion DNA barcoding can be applied to identify the common rodent species in Fujian province as a supplement to morphological identification.

Objective To investigate the type and range of natural focus of hemorrhagic fever with renal syndrome (HFRS) in Fujian province, China, and to provide a scientific basis for the prevention and control of this disease. Methods An investigation of host animals of HFRS was carried out in 15 surveillance sites between 2009 and 2017. Rodents were captured using cages at night, and the rodent density and constituent ratios were calculated. Immunofluorescent assay was used to detect and identify hantavirus (HV) antigen in rodent lungs. Results The mean rodent density was 7.05% in the 15 surveillance sites, and Rattus norvegicus, which carried Seoul HV, was the dominant species. The mean virus-carrying rate of rodents was 6.27%, and R. norvegicus accounted for 83.78%. The mean virus-carrying index of rodents was 0.07, and Longhai had the highest virus-carrying index of rodents 0.12. HV antigen was detected for the first time from R. norvegicus in the cities or counties of Anxi, Shaxian, Longhai, Zhangpu, Dehua, Wuping, Yunxiao, and Qingliu, and from R. norvegicus and R. tanezumi in the counties of Hua'an, Jiangle, and Mingxi. Conclusion It is confirmed for the first time that there are natural foci of HFRS in the 11 surveillance sites. Rattus norvegicus carrying Seoul HV is the main host animal and source of infection with HFRS. The epidemic area of domestic rodent-type HFRS is spreading to the southern and western areas in Fujian province, and widely distributed.

Faunal records of the genus Eulaelaps distributed in mainland China were reviewed, a total of 19 species of the genus have been described including a new record species ( E. oudemansi) recorded here in China. A key to Chinese known species of the genus Eulaelaps is given. This study provides a basis for the faunal study and classification of the genus Eulaelaps in China.

Objective To investigate the epidemic of hemorrhagic fever with renal syndrome(HFRS) in Fujian province, China and to provide a scientific basis for the prevention and control of this disease. Methods The data on the epidemic of HFRS in 2013-2015 in Fujian province were subjected to statistical analysis. Rodents were captured using cages at night, and the population density and community structure of captured rodents was determined. Hantavirus(HV) antigen was detected and identified from rodent lungs by indirect immunofluorescence assay. Results A total of 1 309 cases of HFRS were reported in Fujian in 2013-2015, with an incidence of 1.16/100 000. The cases were widely distributed, county-level cities, or districts. The cases of HFRS were the highest in Shaowu, Jinjiang and Shishi city. The surveillance of rodents showed that the mean population density of rodents was 6.83% indoors, and Rattus norvegicus, which carried Soul virus, was the predominant species. In the mixed epidemic area,the mean population density of rodents was 5.60% in the field, and Apodemus agrarius was the predominant species. HV antigen was detected for the first time from R. norvegicus and R. tanezumi in Yunxiao, Qingliu, and Mingxi counties. Conclusion Rattus norvegicus is still the main host animal of HFRS in Fujian. The incidence of HFRS was at the highest level in 2013-2015 in Fujian, especially in Shaowu city, Songxi, Zhenghe, and Zhouning counties. Rodent control should be well performed, and HFRS bivalent vaccine should be widely used among the high-risk populations, so as to reduce the incidence and prevent the outbreak of HFRS.

Objective To investigate Leptospira serovars in Fujian province, China, and to provide a scientific basis for the prevention and control of leptospirosis. Methods Five investigation sites were established according to the epidemic situation of this disease. In order to determine the main serovars of Leptospira carried by humans and host animals, Leptospira was cultured with blood, kidney, or urine collected from rats, pigs, and frogs. The level of anti-Leptospira antibody was determined in human and rat sera. Serovars and infection status of Leptospira were analyzed based on these studies. Results The investigation of hosts showed that the population density of rodents was 5.83% in the open air of the main epidemic area. Main species were Rattus tanezumi, R. losea, and Niviventer fulvescens, which accounted for 29.87%, 28.19%, and 17.11%, respectively. Leptospira was first isolated from N. coxingi in Changtai county. The positive rate of serum antibody in rats was 11.04%. Autumnalis, Australis, and Grippotyphosa were three of the dominant serotypes in rats. The detection rate of serum antibody in humans was 8.25%. Autumnalis, Pyrogenes, Hebdomadis, and Australis were dominant serotypes in humans. Conclusion The serovars of Leptospira carried by rats and humans are complex in Fujian, which means leptospirosis surveillance should be well performed.

Objective To study the taxonomy of the genus Haemolaelaps from China. Methods The study was conducted by the morphological taxonomy and comparative morphology of the organism. Results Twenty-three species of the genus Haemolaelaps from China were recorded, and a new key to the species of the genus Haemolaelaps was established. Conclusion This study provides the baseline data for the distribution and classification of the genus Haemolaelaps from China.

【Abstract】 Objective To understand the pattern of epidemic areas of hemorrhagic fever with renal syndrome (HFRS) in Fujian and to provide scientific basis for its prevention and control.  Methods Rats were captured in springs and autumns by live snap method, and its density and specie composition were investigated. The virus antigen from rodent lungs was isolated and identified. Results The dominant species in residential areas was Rattus norvegicus in Rattus type areas and the mixed?type area, which density were 4.91% and 5.73% at home respectively. While in the field, it was Apodemus agrarius with the average density of 12.95%, which was obviously higher in autumn and winter than that in spring. R.norvegicus mainly carried with Type Ⅱ virus, and Ap.agrarius with Type Ⅰvirus. A44 and R50 virus strain were isolated from them, respectively. Conclusion R.norvegicus was still the main host of HFRS in Fujian. Ap.agrarius was the main host in the field in the diversity epidemic area. It should strengthen the surveillance and the control of HFRS in main epidemic areas.

Objective To establish a sensitive and specific method for detecting total antibodies in sera of hemorrhagic fever with renal syndrome(HFRS) patients and rodents by the double antigens sandwich ELISA. Methods The double antigens sandwich ELISA was established with coating antigen e1.3S from Hantavirus (HV), combining with recombinant antigen e6-119 labeled with HRP. The method was used to detect total antibodies in sera of HFRS patients and rodents, and the results were compared to that of indirect fluorescent assay(IFA). Results Five hundred and sixty-six samples (188 human sera and 378 rodents sera) were detected by using the double antigens sandwich ELISA and IFA. The total coincidence rate of the results by the two methods was 97.70%. Compared with IFA, the ELISA for the detection of total antibodies showed 97.54% in sensitivity and 97.87% in specificity. Conclusion The double antigens sandwich ELISA showed higher sensitivity and specificity for the detection of total antibodies, which can be applied in the large-scale epidemiologic survey.

The blood sucking activity of Xenopsylla cheopis at high and low temperatures was determined with ¹²⁵Ⅰlabelled method on the host of white mice under laboratory conditions. The result showed that 40Ⅰ and 5℃ were the extremely living temperatures of Xenopsylla cheopis, at which the blood-suching activity became weakness,especially for the females. At lower temperature,5℃～15℃, the blood-sucking rate was highest at 10℃ and lowest at 5℃. The blood-sucking capacity of the females reduced obviously as the droping of temperature, but no significant difference for that of the males.