Objective: To analyze the incidence of hemorrhagic fever with renal syndrome (HFRS) in the human population, along with data from host animal surveillance and viral genetic evolution and typing, in the Zhoushan islands of Zhejiang Province, to provide a scientific basis for local HFRS prevention and control. Methods: The HFRS epidemic data in Zhoushan City from 1985 to 2024 were analyzed. Epidemiological investigations for case, rodent surveillance, and specimen collection were conducted between 2017 and 2024. Rodent species were identified using a combination of morphological and molecular biology methods. Nucleic acids of Hantavirus(HV) from rodent lung tissues and patient serum samples were detected via reverse transcription real-time quantitative PCR. Samples with cycle threshold (Ct) values less than 25 were sent for next-generation sequencing. Nucleotide sequences were aligned using MEGA 7.0 software, and a phylogenetic tree was constructed by the neighbor-joining method. Results: From 1985 to 1996, the annual incidence rate of HFRS was 2.51/100 000, with farmers accounting for the majority of cases (249/291, 85.57%); From 2017 to 2024, the annual incidence rate of HFRS was 0.08/100 000, with 6 locally new reported cases: 1 fisherman, 1 vegetable market vendor, and 4 workers, all confirmed to be infected with Seoul virus. Rattus norvegicus was the dominant species (327/521, 62.76%) of the captured rodents. The rodent densities in Dinghai District, Putuo District, and Daishan County were 5.31%, 4.96%, and 4.73%, respectively. Statistical analysis showed no significant difference in rodent density among the three areas (χ²=1.125, P=0.570). The rodent HV carriage rate was 7.68% (40/521), with a statistically significant difference observed among counties (districts) (χ²=8.404, P=0.015). The nucleotide similarity of Seoul virus S fragments among the 4 strains from Dinghai District, the 5 strains from Putuo District, and the 3 strains from Daishan County was 99.90%-100%, 99.90%-100%, and 97.70%-98.20%, respectively. The S fragment of the strain ZJDSD3 from Daishan County exhibited high homology with the strains from four HFRS patients reported in Daishan County and Putuo District in recent years. Comparative analysis of the S fragments revealed sequence homology of 98.40% between Dinghai and Putuo districts, 97.20%-98.20% between Dinghai District and Daishan County, and 96.10%-99.40% between Putuo Distrct and Daishan County. Conclusions: The epidemic transmission pattern of HFRS in the Zhoushan islands has shifted from traditional agriculture-related sources to urban occupational exposure. Zhoushan islands constitute an epidemic area with only the S3 genotype of Seoul virus. Viral evolution is characterized by the formation of unique local lineages and the relatively independent evolution of different introduced lineages. It is recommended to strengthen multi-environmental surveillance and seroepidemiological studies in the future to support precise prevention and control.

Objective: To investigate the flight capacity of Chrysomya megacephala across different ages in days and sexes, to provide a scientific basis for its control. Methods: Flight mills system were used to conducted 24-hour tethered flight experiments to test male and female C. megacephala flies aged 1, 5, 9, 13, 17, 21, 25, 29, and 33 days under controlled conditions (temperature, 25℃; relative humidity, 30%-40%; illuminance, 565 lx). Statistical analysis of the flight data was conducted using R 4.0.4 software. Normally distributed data are presented as (${\bar x}$±s) and were compared using ANOVA followed by Tukey's test for group differences. Non-normally distributed data are expressed as M (P₂₅, P₇₅) and were analyzed using the Kruskal-Wallis H test for intergroup comparisons. The Scheirer-Ray-Hare test was employed for two-way comparisons. Results: The maximum single-flight distance of C. megacephala adults was significantly influenced by day-age (H=2.453, P=0.014), sex (H=5.172, P=0.024). Day-age (H=2.315, P=0.021) and sex (H=4.474, P=0.035) significantly affected the flight velocity during the maximum single-flight distance of the adult flies. Females exhibited the highest body weight and the maximum single-flight distance [M(P₂₅, P₇₅)=7 281.27 (577.27, 9 774.44) m] at 29 days old, when the longest flight by an individual was recorded, reaching 35 450.99 m. In males, the maximum single-flight distance peaked at 33 days old [M(P₂₅, P₇₅)=1 976.69 (198.08, 2 872.99) m], with the longest flight by an individual observed at 9 days old (6 428.96 m). Conclusions: The flight capacity of C. megacephala varies significantly with age in days and sex, and females show better flight performance than males. These findings provide essential insights into the species' dispersal potential, which can contribute to the prevention and control of fly-vectored pathogens.

Objective: To clarify the effects of ten volatile compounds on the olfactory behavior of Aedes albopictus, and evaluate their potential as spatial repellents. Methods: A wind tunnel test system was employed to assess the behavioral responses of Ae. albopictus to ten volatile compounds: ethanol, acetic acid, eugenol, citronella oil, DL-menthol, geraniol, thymol, 2-undecanone, (E)-6, 10-dimethyl-5, 9-undecadien-2-one, and a commercial mosquito repellent lotion. The feasibility of using these compounds was further evaluated by analyzing their average volatilization rates under controlled conditions. We used Student's t-test to compare the selection rates between the treatment and control groups, and Tukey's multiple comparison test to analyze the differences in mean volatilization rates. Results: When acting alone, citronella oil, acetic acid, (E)-6, 10-dimethyl-5, 9-undecadien-2-one, 2-undecanone, eugenol, and mosquito repellent lotion exhibited significant repellency against Ae. Albopictus, with statistically significant differences in selection rates between treatment and control groups (all P < 0.05). However, when combined with host odors, citronella oil, (E)-6, 10-dimethyl-5, 9-undecadien-2-one, DL-menthol, mosquito repellent lotion, geraniol, eugenol, and 2-undecanone exhibited significant repellency against Ae. Albopictus, with statistically significant differences in selection rates between treatment and control groups (all P < 0.05). Notably, citronella oil induced highly significant repellency against Ae. Albopictus, both when acting alone and in the presence of host odors, resulting in selection rates of 23.33% and 13.40%. Under experimental conditions of 25 ℃ and an airflow speed of 0.2 m/s, a significant difference in the average volatilization rates was observed among the ten compounds (P < 0.05). The average volatilization rate of citronella oil was 0.33 mg/min. Conclusion: Citronella oil exhibits superior repellent performance and a low volatilization rate, demonstrating practical value as a spatial repellent against mosquitoes.

Objective: To conduct nucleic acid detection and whole-genome sequencing analysis of Dabie bandavirus (DBV) in serum samples from the first identified case of severe fever with thrombocytopenia syndrome (SFTS) in Changshan County, Zhejiang Province, to provide technical support for the prevention and control of SFTS in Changshan County. Methods: Serum samples from the patient and related vector specimens were collected. Reverse transcription real-time quantitative PCR (RT-qPCR) was used to detect DBV nucleic acids, while reverse transcription PCR (RT-PCR) was employed to amplify DBV-specific genetic fragments for whole-genome sequencing. ClustalⅩ, BioEdit V7.2.6.1, and MEGA 7 softwares were utilized for nucleotide and amino acid sequence alignment, as well as phylogenetic analysis. Results: The serum tested positive for DBV nucleic acids via RT-qPCR. Subsequent amplification and sequencing yielded three genomic segments (L, M, and S). Phylogenetic analysis indicated that the DBV gene sequence from Changshan County clustered within the genotype A branch. Nucleotide homologies with the human-derived genotype-A reference strain JS2015-01 isolated in Jiangsu Province for the L, M, NS, and NP genomic segments were 99.79%, 99.84%, 99.66%, and 100%, respectively, while amino acid homologies were 99.95%, 99.81%, 99.66%, and 100%, respectively. Compared with a tick-derived genotype-A reference strain, the nucleotide homologies were 98.61%, 98.51%, 98.87%, and 98.24%, respectively, and the amino acid homologies were 99.76%, 99.44%, 99.32%, and 100%, respectively. The average genetic distances for the L, M, and S genomic segments with human-derived genotype-A reference strain were all 0.002, while those with the tick-derived genotype-A reference strain were 0.014, 0.015, and 0.014, respectively, accompanied by varying degrees of amino acid substitutions at specific sites. Conclusions: The identified strain was confirmed as DBV, closely related to a human-derived reference strain, and classified as genotype A. The transmission route remains unclear.

Objective: To investigate the distribution of genotypes and subtypes of Hantavirus in rodents at the national surveillance site in Weifang, Shandong Province and understand the molecular epidemiological characteristics of Hantavirus, to provide a theoretical foundation for the prevention and control of hemorrhagic fever with renal syndrome (HFRS). Methods: In 2023, rodent lung specimens were collected from Qingzhou, Anqiu, Gaomi, Linqu, and Changle counties (county-level cities) in Weifang. Different types of Hantavirus [Hantaan virus and Seoul virus (SEOV)] in rodent lung tissues were detected using TaqMan fluorescent probe-based reverse transcription real-time quantitative polymerase chain reaction. Chi-square test was used to compare infection rates. Spearman correlation analysis was employed to assess the correlations of HFRS incidence with rodent density and Hantavirus positive rates. The genomic sequences of S segments were amplified by reverse transcription polymerase chain reaction, followed by nucleotide homology analysis and phylogenetic analysis. Results: A total of 202 rodents were captured, including 163 Rattus norvegicus, 29 Mus musculus, 7 Apodemus agrarius, and 3 R. sacer. Twenty samples tested positive for Hantavirus, all identified as SEOV, resulting in a positivity rate of 9.90% (20/202). Hantavirus was exclusively detected in R. norvegicus, which showed a Hantavirus positive rate of 12.27% (20/163). R. norvegicus from different regions showed significant differences in Hantavirus positive rates (χ²=14.585, P=0.006). Hantavirus was only detected in two habitats: rural residential areas (7/104, 6.73%) and livestock farms (13/84, 15.48%), with no statistically significant difference in Hantavirus positive rates between these habitats (χ²=3.738, P=0.053). No significant difference was observed in Hantavirus positive rates between female (9/104, 8.65%) and male (11/98, 11.22%) rodents (χ²=0.374, P=0.541). No significant correlations were found between HFRS incidence and rodent density (r=0.600, P=0.285) or Hantavirus positive rates (r=0.154, P=0.805) across different regions. Nine SEOV S segments were obtained and phylogenetic analysis showed that all these viruses belonged to the S3 genotype. The homology of the viral nucleotide sequences was between 98.44% and 100%, and that of the amino acid sequences was between 97.12% and 100%. Conclusions: Hantavirus infection was detected in the rodents in Weifang, with the SEOV (S3 genotype) being predominant. It is necessary to enhance the detection of rodent-borne pathogens and the surveillance of related diseases in Qingzhou City, Anqiu City and Linqu County key areas, and formulate region-specific prevention and control strategies for rodent-borne diseases.

Objective: To analyze the rodent surveillance data in Guangzhou, 2015-2024, and investigate the seasonal variation of rodent density and the differences in rodent density among different types of habitat, to provide a basis for formulating scientific rodent prevention and control measures. Methods: Rodent density surveillance data from 2015 to 2024 in Guangzhou were collected and analyzed to assess annual and monthly trends in rodent density and species composition. The Chi-square test was used to compare the differences in rodent density across different types of habitat. A Jointpoint regression model was employed to examine the seasonal fluctuation patterns of rodent density. Results: From 2015 to 2024, the average rodent density in Guangzhou was 2.40%, with Rattus norvegicus accounting for 76.51% (3 579/4 678) of the captured specimens. There was a significant difference in average rodent density across different years (χ²=173.047, P < 0.001). The average rodent density was the lowest (1.81%) in 2020. The average rodent density in Guangzhou generally decreased from 2015 to 2024 [annual percent change (APC)=-4.297, P=0.031]. From 2015 to 2024, the monthly rodent density showed a gradual increase from January to June [monthly percent change (MPC)=5.222, P < 0.001], and a gradual decrease from June to December (MPC=-7.419, P < 0.001). The monthly rodent densities of R. norvegicus and Mus musculus showed a gradual increase from January to June and a gradual decrease from June to December. The average rodent densities in urban residential areas, key industries, rural residential areas, and other habitats were 2.23%, 2.11%, 3.03% and 2.75%, respectively, and the difference was statistically significant (χ²=114.741, P < 0.001). The rodent densities in urban residential areas and key industries both increased and then decreased, reaching their peaks in July and June, respectively. Conclusions: From 2015 to 2024, the rodent density in Guangzhou fluctuated at a relatively high level but showed an overall declining trend. R. norvegicus was the dominant rodent species in Guangzhou. The rodent density was relatively high in rural residential areas. These results suggest that comprehensive prevention and control measures should be taken according to the seasonal fluctuations of rodent density.

Objective: To analyze the population dynamics of mosquitoes and the correlation between meteorological factors and mosquito density in Daxing District, Beijing, 2020-2024, to provide a theoretical basis for formulating mosquito density control and mosquito-borne disease prevention strategies. Methods: From May to October annually during 2020-2024, mosquito density surveillance was conducted in five types of habitats (residential areas, park green spaces, hospitals, residential houses, and livestock farms) within Daxing District using CO₂-baited light traps method. The Chi-square test was used to analyze the annual differences in the species composition of mosquito, one-way ANOVA was used to compare the differences in mosquito density among habitats, and Pearson correlation and stepwise multiple linear regression models were used to explore the association between meteorological factors and mosquito density. Results: In this study, 2 520 traps were deployed, capturing a total of 2 829 adult mosquitoes, yielding an overall density of 0.56 mosquitoes/(light·h). The captured mosquitoes were dominated by Culex pipiens pallens (2 125, 75.11%) and Aedes albopictus (704, 24.89%). Overall, mosquito density exhibited a fluctuating trend over time. The dominance of Cx. pipiens pallens continued to decline, with its density decreasing from 0.83 mosquitoes/(light·h) in 2020 to 0.23 mosquitoes/(light·h) in 2024, and its proportion decreased from 90.83% to 47.22%. In contrast, the population of Ae. albopictus increased significantly, with its density rising from 0.08 mosquitoes/(light·h) in 2020 to 0.25 mosquitoes/(light·h) in 2024, and its proportion substantially increasing from 9.17% to 52.78%. Mosquito density exhibited a monophasic seasonal fluctuation pattern, peaking between July and September. Mosquito densities in park green spaces and residential premises were both 0.70 mosquitoes/(light·h), higher than in other habitats. The monthly minimum temperature (β=0.122, P < 0.001) and the monthly average atmospheric pressure (β=0.065, P=0.011) were included in the multiple linear regression model. The regression equation was y = 0.12x₁ + 0.07x₂ - 65.284 (x₁: monthly minimum temperature; x₂: monthly average atmospheric pressure), with an adjusted R² of 0.447, indicating a high goodness of fit. Conclusions: Mosquito density in Daxing District fluctuated during the study period, peaking from July to September, with relatively high densities observed in park green spaces and residential premises. Mosquito density was significantly associated with monthly minimum temperature and monthly mean atmospheric pressure. It is recommended that, in addition to comprehensive mosquito prevention measures, enhanced surveillance and targeted control measures should be implemented for Ae. albopictus, with a focus on advancing breeding site cleanup and habitat management to reduce the epidemic risk of mosquito-borne diseases such as dengue fever.

Objective: To investigate the density, distribution, and seasonality of Aedes albopictus populations in Qingpu District, Shanghai, China from 2021 to 2023, to provide a basis for the control of Ae. albopictus density and the early warning of related infectious diseases in the region. Methods: Ae. albopictus populations were monitored using the mosq-ovitrap method. The mosq-ovitrap index (MOI) was analyzed by year, town/sub-district, month, and habitat using Pearson's Chi-square test and the Chi-square test for trend. Results: From 2021 to 2023, a total of 32 900 ovitraps were deployed across the district, with 32 400 recovered, in which 2 240 were positive for Ae. albopictus (MOI=6.91). MOI differed significantly across different years, months, habitats, and towns/sub-districts (all P < 0.05). From 2021 to 2023, the MOI of Ae. albopictus showed a unimodal pattern from May to October of each year, with the peaks concentrated in June (9.45) or July (8.56). Among various habitats, residential areas had the highest MOI in June (12.50), while other outdoor environments had the highest MOI in the remaining months. Across Qingpu District, MOI values were higher in Zhaoxiang Town (13.92), Jinze Town (9.48), and Zhujiajiao Town (9.28). Among the 11 towns/sub-districts, MOI peaked in June in Zhaoxiang Town, Chonggu Town, Xujing Town, and Xiayang Sub-district; in July in Zhujiajiao Town and Jinze Town; in August in Yingpu Sub-district; and in September in Baihe Town. The habitats with the highest MOI were hospitals in Xujing Town and Huaxin Town; residential areas in Xiayang Sub-district, Yingpu Sub-district, and Baihe Town; schools in Chonggu Town; and other outdoor environments in the other areas. Conclusions: MOI peaks and high-MOI habitats for Ae. albopictus differ across the towns/sub-districts of Qingpu District, Shanghai. Relevant departments can carry out targeted vector control measures and health education on mosquito prevention and elimination, based on the peak months for Ae. albopictus MOI and the habitats with high MOI in different months.

Objective: To investigate the common species, density, seasonality, and insecticide resistance levels of flies in Hohhot, the Inner Mongolia Autonomous Region, China, to provide a scientific basis for fly control. Methods: In 2024, fly surveillance was conducted using the cage trapping method in the nine banners (districts and counties) of Hohhot. Using SPSS 27.0, Chi-square tests were performed to compare fly species composition across various habitats, and the Kruskal-Wallis H test for multiple independent samples was conducted to compare fly density. Houseflies (Musca domestica) were collected using sweep nets, and then separately caged in a rearing room to breed for two generations for insecticide resistance assessment. The median lethal dose, regression equation, and resistance ratio (RR) were calculated. Results: In 2024, a total of nine species of flies were captured in Hohhot, and the top three fly species by composition ratio were M. domestica, Sarcophagidae flies, and Muscina stabulans, accounting for 68.95%, 10.92%, and 7.35% of the total catches, respectively. The annual average fly density was 5.49 flies/cage. The highest fly density was recorded in farmers' markets. Fly density peaked during July to September, with the monthly average densities being 6.45, 6.65, and 6.87 flies/cage, respectively. The resistance of houseflies to beta-cypermethrin was highest (RR, 90.20-214.99). Across all the surveyed banners (counties) and the urban area, houseflies exhibited moderate-to-high resistance to beta-cypermethrin, propoxur (RR, 26.88-263.10), lambda-cyhalothrin (RR, 59.53-189.01), alpha-cypermethrin (RR, 43.07-128.97), and deltamethrin (RR, 27.12-61.25). Houseflies in the urban area and Tuoketuo County were moderately resistant to deltamethrin and propoxur, and the populations in the other areas of Hohhot were highly resistant to the above five insecticides. Conclusions: In 2024, M. domestica was the dominant fly species in Hohhot. Farmer's markets were the key habitats for fly prevention and control. July to September was the peak period for fly activity. Across all the banners (counties and districts), M. domestica developed moderate-to-high resistance to commonly used insecticides, suggesting that the use of beta-cypermethrin, propoxur, lambda-cyhalothrin, alpha-cypermethrin, and deltamethrin should be suspended or reduced, and sensitive insecticides with low resistance should be selected for gradual rotation.

Objective: To investigate the species, distribution characteristics, parasitic status, and seasonal fluctuations of ticks on animal surfaces in human settlements and surrounding environments in Nanchang, China, to provide a basis for formulating scientific and effective prevention and control strategies for tick-borne diseases. Methods: From 2023 to 2024, four representative areas in Nanchang, i.e., Honggutan District, Nanchang County, Xihu District, and Xinjian District (including Wanli Management Area), were selected for tick collection. Free-living ticks were collected from different habitats using the tick flag-dragging method, while parasitic ticks were collected from animal hosts using the host body tick checking method. After tick species identification, indicators such as tick density index, tick infestation rate, and tick index were calculated. Differences in tick infestation rates across different regions and different host animals were analyzed using the Chi-square test, while the Kruskal-Wallis H test was used to analyze parasitic tick index and free-living tick density across different regions. Results: A total of 1 032 ticks were collected during the study period, including 230 free-living ticks and 802 parasitic ticks, belonging to 1 family, 3 genera, and 10 species. Haemaphysalis longicornis was the dominant species in Nanchang, accounting for 36.73% (379 ticks). The differences in tick infestation rate, parasitic tick index, and free-living tick density across different regions were all statistically significant (χ²=158.655, P < 0.001; H=8.004, P=0.046; H=11.070, P=0.011). The differences in tick infestation rate and tick index among different host animals were also statistically significant (χ²=46.459, P < 0.001; H=16.644, P=0.002). The density of free-living ticks was higher in April, June, and October. Forest habitats had the highest tick density index of 0.65 ticks/(flag·100 m), significantly higher than other habitats. Among host animals, sheep had the highest infestation rate of 34.35%(113/329), with a tick index of 1.12, cattle had the highest tick index of 1.90, and dogs hosted a greater variety of parasitic tick species. Conclusions: Nanchang has a rich diversity of tick species, with sheep being the dominant host. Free-living ticks are most active in forest habitats, and April, June, and October are the active periods for free-living ticks. Strengthening surveillance of ticks and tick-borne diseases is essential.

Objective: To examine how environmental and socioeconomic factors modify the association between temperature and hemorrhagic fever with renal syndrome (HFRS) across different types of HFRS epidemic regions in China. Methods: HFRS surveillance data from 2005 to 2022 were collected alongside contemporaneous temperature measurements, environmental variables, and socioeconomic indicators in China. Based on prior research, epidemic regions were classified according to the seasonal distribution patterns of cases at the prefecture level into Seoul virus (SEOV)-dominant regions (primarily carried by Rattus norvegicus), Hantaan virus (HTNV)-dominant regions (primarily carried by Apodemus agrarius), and mixed epidemic regions. Environmental conditions were measured by the normalized difference vegetation index (NDVI), calculated as the monthly average NDVI for each prefecture during the study period. Socioeconomic status was represented by gross domestic product (GDP) per capita, population density, and urbanization rate, each categorized into low, medium, and high levels using tertiles. A time-stratified case-crossover design integrated with a distributed lag non-linear model was applied to comprehensively assess the exposure-response relationship between temperature and HFRS under varying environmental and socioeconomic levels across different types of epidemic regions. Results: The exposure-response relationship between temperature and HFRS exhibited a nonlinear, inverted U-shaped curve, with significantly increased epidemic risk at moderate temperatures. Likelihood ratio tests indicated that NDVI significantly modified the association in SEOV-dominant, HTNV-dominant, and mixed epidemic regions, with the highest HFRS risks consistently observed in regions with low NDVI, suggesting that temperature exerted a more pronounced promoting effect on HFRS transmission in regions with low vegetation coverage. In HTNV-dominant regions, medium NDVI showed a significant protective effect, attenuating the promotion of HFRS transmission by moderate temperatures. GDP per capita significantly modified the association in HTNV-dominant and mixed regions. In HTNV-dominant regions, GDP per capita was negatively correlated with the risk of HFRS transmission at temperatures ranging from -5 ℃ to 10 ℃. In mixed epidemic regions, the regions with medium GDP per capita showed the highest HFRS risk within 10 ℃-20 ℃. Population density was a significant modifier across all three epidemic regions. In HTNV-dominant and mixed epidemic regions exposed to medium temperature ranges, the regions with lower population density were associated with higher HFRS risk. Urbanization rate significantly modified the association in HTNV-dominant and mixed epidemic regions. In mixed epidemic regions, a higher urbanization rate was associated with greater HFRS risk under temperature exposure. Conclusion: NDVI, GDP per capita, population density, and urbanization rate all demonstrate significant modification effects on the association between temperature and HFRS risk.

Objective: To analyze the clinical and epidemiological characteristics of psittacosis cases reported in Beijing, China, investigate the basic situation of psittacosis cases in the city, to provide a scientific basis for the prevention and control of psittacosis. Methods: An epidemiological investigation was conducted on psittacosis cases reported in Beijing between 2023 and 2024. Data were analyzed using descriptive epidemiological methods. With informed consent obtained from patients or their family, clinical specimens from patients and avian-related samples (bird feces, cloacal swabs, cage swabs, and feeder swabs) were collected for laboratory tests. Fisher's exact probability test was applied to compare differences in intensive care unit (ICU) admission rate between patients reported in different years. Results: A total of 64 psittacosis cases were reported in Beijing, 2023-2024. The male-to-female ratio was 1.06:1, and the mean patient age was (59.73±12.39) years, with the majority (89.06%, 57/64) aged 40-80 years. No distinct seasonal pattern was observed in case reports, though relatively high numbers were recorded in April and May. Cases were distributed across 11 districts of Beijing, with the highest concentrations in Daxing, Shunyi, and Changping districts. The most affected groups were retirees (n=17) and homemakers/unemployed individuals (n=17). Confirmed domestic bird exposure history was documented in 81.25% (n=52) of cases, with parrots (Psittaciformes) and pigeons (Columbidae) identified as the primary birds involved. Notably, 60.94% (39/64) of cases were confirmed pet bird owners. Major clinical manifestations included fever (62/64, 96.88%), fatigue (20/64, 31.25%), and cough (15/64, 23.44%). Additionally, 62 (96.88%) cases required hospitalization, and 13 cases (20.31%) required ICU admission. A statistically significant difference in ICU admission rate was observed between cases reported in 2024 versus those from 2023 and earlier years (P=0.001). Conclusions: Psittacosis currently demonstrates a low-level endemic circulation in Beijing. The majority of psittacosis cases were associated with clear exposure to birds such as parrots, and severe cases were documented. Enhanced surveillance, standardized outbreak management, and strengthened health education targeting high-risk populations are recommended. Additionally, interdepartmental collaboration should be reinforced to improve disease control management for parrots and other birds.

Objective: To investigate the risk factors for mortality in patients with severe fever with thrombocytopenia syndrome (SFTS), to provide a scientific basis for developing targeted prevention and treatment strategies. Methods: The clinical data of 326 patients with SFTS in Chaohu, Anhui Province, China from January 2013 to December 2024 were retrospectively analyzed. The patients were divided into non-surviving group (64 cases) and surviving group (262 cases) based on their outcomes 28 days post discharge. Basic characteristics and clinical data were compared between the two groups using the Chi-square test or Mann-Whitney U test. Univariable analyses and binary logistic regression models were used to identify mortality-related risk factors. Results: The overall mortality rate of the SFTS cases was 19.63%(64/326). The non-surviving and surviving groups differed significantly in terms of age, time from onset to first medical visit, the number of complications, the presence or absence of fever as the initial symptom, viral load, platelet count, potassium, calcium, creatinine, procalcitonin, alanine transaminase, aspartate transaminase, creatine kinase, creatine kinase-MB, prothrombin time, the international normalized ratio, activated partial thromboplastin time, thrombin time, and D-dimer (all P < 0.05). The binary logistic regression analysis further revealed that age, creatinine, and D-dimer were independent risk factors for mortality in patients with SFTS (all P < 0.05). For the three indicators, the areas under the receiver operating characteristic curves were 0.682, 0.666, and 0.713, respectively, and the cut-off values were 73.5 years old, 77.5 μmol/L, and 2.39 μg/ml, respectively. Conclusions: Advanced age, elevated creatinine levels, and elevated D-dimer levels are independent risk factors for mortality in patients with SFTS. Early monitoring of these indicators is necessary for accurate assessment and individualized intervention to reduce mortality risk.

Objective: To understand the epidemiological characteristics of imported and local dengue fever cases in Hunan Province in 2019, analyze the etiological features of dengue viruses (DENV), to provide a theoretical basis for dengue fever prevention and control. Methods: An epidemiological analysis was conducted on data from dengue fever cases reported in Hunan Province in 2019. The Chi-square tests were performed using SPSS 20.0 to compare gender, age distribution, and occupational distribution of the cases. Real-time quantitative PCR was used to detect DENV and its serotypes in serum samples. Whole-genome sequencing was performed on DENV-positive specimens from different regions. Homology and phylogenetic analyses were performed using MEGA 7.0 software. Results: In 2019, a total of 748 dengue fever cases were reported in Hunan Province, including 429 imported cases and 319 local cases. Statistical analysis revealed significant differences between imported and local cases in gender ratio, age distribution, and occupational distribution (χ²=48.068, 111.937, 109.795, all P < 0.001). Imported cases were concentrated from May to October, local cases were clustered in September and October, demonstrating district seasonality. All four DENV serotypes (DENV-1 to DENV-4) were detected among imported cases, while only DENV-1 and DENV-2 were detected in local cases. DENV-1 strains of imported and local cases belonged to genotype Ⅰ, DENV-2 strains of imported and local cases were genotype Ⅱ, DENV-3 strains of imported cases were genotype Ⅲ, and DENV-4 strains of imported cases were genotypeⅠ. DENV-1 and DENV-2 of local cases were detected in Changsha. Conclusions: Four dengue virus serotypes were identified among imported cases, while only DENV-1 and DENV-2 were detected in local cases in Hunan Province in 2019, local dengue fever outbreaks in multiple cities were triggered by secondary transmission originating from imported cases. Comprehensive preventive measures are needed to reduce the incidence and spread of dengue fever and to prevent severe cases.

Objective: To perform a metagenomic sequencing analysis of six bed bugs captured during the first bed bug infestation event reported in Dadukou District, Chongqing, China and analyze the characteristics of their microbial communities and the molecular features of Wolbachia, to provide a scientific basis for the investigation of this event and the development of new strategies for bed bug control. Methods: First, morphological identification was used to determine the species of the bed bugs. Next, metagenomic sequencing was performed to decipher the microbial community within the bed bugs. The α-diversity indices were employed to assess the diversity of microbial communities within the six bed bugs, combined with β-diversity analyses to compare differences in microbial communities among different bed bug specimens. Multilocus sequence typing (MLST) of Wolbachia was performed on the basis of five housekeeping genes. A core-genome single-nucleotide polymorphism data set of Wolbachia was used to construct a maximum-likelihood phylogenetic tree to resolve relationships among strains. Results: All the six bed bugs were identified as Cimex lectularius. The diversity of their microbial communities was extremely low, with the Shannon and Simpson indices being less than 0.200. The microbiota was mainly composed of symbiotic microorganisms, including Wolbachia, Plautia stali symbiont, Arsenophonus nasoniae, Sodalis glossinidius, and Komagataella phaffii. No known human pathogenic bacteria was detected in significant abundance. The β-diversity analysis revealed differences in the microbial community composition among the six bed bugs. MLST of Wolbachia identified all strains as ST8 type [coxA(27)-fbpA(28)-ftsZ(24)-gatB(26)-hcpA(31)]. Phylogenetic analysis showed that the Wolbachia strains of specimens 1, 4, and 5 clustered on the same evolutionary branch, indicating relatively close evolutionary relatedness. Conclusions: The current infestation in Dadukou District is confirmed as caused by C. lectularius, with a low direct risk of vector-borne infectious diseases following bites. Microbial profiling of the six bed bugs indicates extremely low microbial community diversity with a highly skewed distribution. Strikingly, ST8-type Wolbachia dominates the symbiotic microbiota, demonstrating remarkable potential for application in the control of C. lectularius.

Objective: To understand the composition and distribution characteristics of fleas in Lingwu City, Ningxia Hui Autonomous region, China, to provide a scientific basis for the prevention and control of plague and other natural focal diseases. Methods: Surveillance data on plague and faunal surveys of animals and insects in Lingwu City from 2009 to 2024 were collected and systematically reviewed. The collected fleas were classified, identified, and counted. A flea checklist was compiled following the established flea classification system. Results: Between 2009 to 2024, a total of 16 891 host animals, belonging to 17 species of 13 genera in 8 families, were investigated. The dominant species were Meriones unguiculatus and M. meridianus, collectively accounting for 83.84% (14 162/16 891) of the total. A total of 743 host nests were examined, of which 435 were infested with fleas, resulting in a nest infestation rate of 58.55% and a flea index of 1.89. A total of 25 474 fleas, belonging to 26 species (or subspecies) of 13 genera in 5 families, were collected, of which 24 070 were ectoparasitic fleas and 1 404 were nest fleas. The dominant flea species were Xenopsylla conformis and Nosopsyllus laeviceps, collectively accounting for 86.77% (22 103/25 474) of all fleas collected. Combining these findings with historical records, a total of 36 flea species (or subspecies) of 17 genera in 6 families were documented for Lingwu City, including 10 newly recorded for the city. Conclusions: Flea species in Lingwu City are diverse. The dominant flea species, X. conformis and N. laeviceps, are the main vectors of in the plague natural focus.

Objective: To investigate the population composition and Japanese encephalitis virus (JEV) carriage of mosquitoes in Chaoyang District, Beijing, to provide a basis for the prevention and control of Japanese encephalitis. Methods: Between August and September 2024, mosquitoes were collected using the CO₂-baited light trap method across residential areas, wetland parks, and animal breeding sites in Chaoyang District. Mosquitoes were pooled in batches of 50 individuals/tube. Detection of JEV was performed using reverse transcription real-time quantitative PCR (RT-qPCR). The C/PrM gene of JEV was amplified via nested PCR, and the products were submitted for sequencing. Mosquito specimen data were organized using Excel 2021. Viral gene sequences were analyzed using DNASTAR 18.0 and MEGA 12.0 softwares. Results: A total of 12 063 mosquitoes (9 species of 6 genera) were collected. The three most abundant species were Culex pipiens pallens (6 648/12 063, 55.11%), Culex tritaeniorhynchus (3 116/12 063, 25.83%), and Aedes albopictus (917/12 063, 7.60%), with other species such as Armigeres subalbatus presented in relatively low numbers. A total of 231 specimen batches were tested using RT-qPCR, of which 4 batches tested positive for JEV, resulting in a positivity rate of 1.73% (4/231). Two C/PrM gene sequences of JEV were successfully obtained from Cx. tritaeniorhynchus and Ae. vexans. Both sequences belonged to genotype Ⅰ of JEV and showed the higher similarity to the Sichuan strain (2020), the Guizhou strain (2021), and the Ningxia strain (2023). Conclusions: The predominant mosquito species in Chaoyang District of Beijing are Cx. pipiens pallens, Cx. tritaeniorhynchus, and Ae. albopictus. The circulation of JEV among mosquitos may partially contribute to sporadic local cases of Japanese encephalitis reported in recent years. It is essential to enhance vector surveillance and control measures, and further investigate the mechanisms of JEV circulation in urban environment.

Objective: Analyze the bioassay data on insecticide resistance in Blattella germanica in China to understand the distribution of insecticide types, temporal trends, and geographical patterns, with the aim of providing data support for the chemical control of B. germanica. Methods: The search terms "Blattella germanica" "insecticide resistance" "residual film method" or "topical application method" were used to retrieve all relevant articles from the databases of China National Knowledge Infrastructure (CNKI, 1994-2024), Wanfang Data Knowledge Service Platform (Wanfang, 1998-2024), VIP Chinese Journal Service Platform (VIP, 1989-2024), and the PubMed (1966-2024). Excel 2013 software was used to organize the data, and SPSS 19.0 software was employed for analysis of variance or t-test. Results: A total of 103 articles were retrieved from CNKI, 93 from Wanfang, 23 from VIP, and 4 from PubMed. A total of 150 publications employed the residual film method for insecticide resistance testing on B. germanica, generating 1 515 data points on median knockdown time (KT₅₀) derived from 24 provinces (autonomous regions and municipalities) in China. A total of 25 insecticides in 5 categories were tested, with pyrethroids being the most represented (14 insecticides). Among the 25 insecticides, propoxur yielded the largest KT₅₀ dataset (277 data points), followed by deltamethrin (266 data points). The data from eight insecticides, including propoxur, deltamethrin, beta-cypermethrin, dichlorvos, acephate, cypermethrin, permethrin, and chlorpyrifos, accounted for 93.20% of the total KT₅₀ data. Temporal analysis (1986-1999, 2000-2004, 2005-2009, 2010-2014, 2015-2019, 2020-2024) revealed statistically significant differences in KT₅₀ values for propoxur, deltamethrin, beta-cypermethrin, dichlorvos, acephate, permethrin, and chlorpyrifos (all P < 0.05). The regional distribution of KT₅₀ data for insecticides varies, with more comprehensive data available in north China and east China, and relatively less in northeast China and northwest China. From 2010 to 2014, there were statistically significant differences in the KT₅₀ values of propoxur and beta-cypermethrin between north and east China regions (t=3.000, P=0.006; t=1.668, P=0.203); Additionally, From 2015 to 2019, there were statistically significant differences in the KT₅₀ values of propoxur and beta-cypermethrin among the north China, east China, central China, and southwest China (F=2.885, P=0.042; F=4.170, P=0.008). Twenty-seven studies employed the topical application method to determine the median lethal dose (LD₅₀) for B. germanica, from 14 provinces (autonomous regions and municipalities). These studies involved 18 insecticides from 5 categories, with pyrethroids being the most represented. The data from six insecticides such as propoxur, cypermethrin, chlorpyrifos, deltamethrin, permethrin and dichlorvos accounted for 88.59% of the 377 LD₅₀ data collected. Significant differences in LD₅₀ values for propoxur, cypermethrin, permethrin, and chlorpyrifos were observed across 1986-1999, 2000-2009, and 2010-2018 for B. germanica (all P < 0.05). For transport vehicles (passenger trains, ships, and aircraft), 19 studies using the residual film method provided 148 KT₅₀ data points for B. germanica. The studies covered 19 insecticides from 5 categories, with pyrethroids being the most represented. Data on KT₅₀ values of B. germanica from vehicles for five insecticides, including deltamethrin, propoxur, beta-cypermethrin, acephate and cyhalothrin accounted for 73.65% of the total dataset. There were no statistically significant differences in KT₅₀ values for deltamethrin, propoxur, and beta-cypermethrin against B. germanica collected from passenger trains and ships (all P > 0.05). Conclusions: The bioassay data for insecticide resistance in B. germanica exhibit temporal and regional variations. Data on resistance obtained through the residual film method are more extensive than those from the topical application method. Considering both simplicity of operation and scientific accuracy, it is recommended to adopt harmonized surveillance methods and evaluation indicators for B. germanica resistance, along with commonly used insecticides, in order to obtain more effective and reliable data support.

Objective: To investigate the prevalence of common pathogens in small mammals in Ganzhou, Jiangxi Province, 2022-2024, to provide a reference for risk assessment and early warning of rodent-borne diseases. Methods: From 2022 to 2024, small mammals were captured in 3 counties (county-level cities, districts) of Ganzhou for morphological identification. Tissue samples from the lungs, liver, spleen and kidneys of small mammals were collected for pathogen detection. Real-time fluorescent quantitative PCR was used to detect Hantavirus, Dabie bandavirus, pathogenic Leptospira, and Orientia tsutsugamushi. WPS office 2023 and SPSS 21.0 softwares were used for data collation and statistical analysis. Positive rates were compared using Chi-square test. A multivariable analysis using binary logistic regression analysis was conducted to identify factors influencing the pathogen positivity in small mammals. Results: A total of 641 small mammals of seven species were captured in Ganzhou, including Rattus norvegicus (274/641, 42.75%), R. tanezumi (107/641, 16.69%), Mus musculus (92/641, 14.35%), R. losea (68/641, 10.61%), Soricidae (64/641, 9.98%), Apodemus agrarius (35/641, 5.46%), and Niviventer confucianus (1/641, 0.16%). The pathogen detection showed that pathogenic Leptospira had the highest positive rate (15.44%), followed by Hantavirus (2.03%), with Hantaan virus detected in three mammals and Seoul virus in ten mammals via phenotyping. The positive rate of O. tsutsugamushi was 1.56%. Co-infection with pathogenic Leptospira and Hantavirus was observed, with an infection rate of 0.47% (3/641). Dabie bandavirus was not detected. The pathogen positive rate in 2024 was 30.43% (63/207), higher than in other years. The difference in pathogen positive rates among different years was statistically significant (χ²=28.543, P < 0.001). There was a linear increase in positive rate across different years (χ$ {}_{\mathrm{t}\mathrm{r}\mathrm{e}\mathrm{n}\mathrm{d}}^{2} $=20.024, P < 0.001). The small mammal species with the highest pathogen infection rate was R. losea (19/68, 27.94%), followed by R. norvegicus (67/274, 24.45%) and M. musculus (15/92, 16.30%). The difference in positive rates among different small mammal species was statistically significant (χ²=24.796, P < 0.001). The positive rate in Longnan City (72/213, 33.80%) was higher than those in Yudu County (23/225, 10.22%) and Shangyou County (24/203, 11.82%). The difference in positive rates among different surveillance areas was statistically significant (χ²=49.176, P < 0.001). Among different habitats, the positive rate was highest in key industries (31.67%, 19/60). The binary logistic regression analysis showed that the positivity of small mammals was associated with mammal species and surveillance area (all P < 0.05). Conclusions: Small mammals in Ganzhou are infected with pathogenic Leptospira, Hantavirus, and O. tsutsugamushi, with pathogenic Leptospira being the predominant pathogen. It is necessary to strengthen the monitoring of pathogens carried by small mammals and enhance the prevention and control of related diseases.

Due to hot and humid climate and diverse mosquito species, Guizhou Province is at high risk for the spread of mosquito-borne infectious diseases. At present, the prevention and control of mosquito-borne diseases primarily relies on mosquito control, which is heavily dependent on the use of chemical insecticides. However, prolonged reliance on chemical insecticides has led to moderate-to-high levels of resistance to pyrethroid insecticides among Anopheles sinensis, Culex pipiens quinquefasciatus, and Aedes albopictus. This paper systematically reviews the current status, mechanisms, and regional differences of insecticide resistance among the three mosquito species in Guizhou Province. It proposes an integrated management strategies centered on insecticide rotation while also promoting resistance surveillance and precise control.