ISSN 1003-8280 CN 10-1522/R 中国疾病预防控制中心 主办
Chikungunya fever (CHIKF), a condition caused by the Chikungunya virus (CHIKV), has triggered a pervasive pandemic in tropical and subtropical regions worldwide in recent years, affecting over 10 million individuals across 125 countries, especially in South and Southeast Asia. China has also experienced a notable increase in imported CHIKF cases, with Foshan (Guangdong Province) witnessing a large-scale CHIKF outbreak in July 2025 that had resulted in more than 9 000 confirmed cases as of August 9, posing a severe threat to public health security. CHIKV is primarily classified into the West African genotype (WA), the East/Central/South African genotype (ECSA), and the Asian genotype (Asian). These genotypes exhibit varying patterns in geographical prevalence and clinical severity. This review presents the distribution of CHIKV genotypes detected in China, and analyzes the risk of CHIKV transmission.
Objective: To evaluate the lethal efficacy of boric acid combined with four cockroach gel baits against Periplaneta americana, so as to provide a scientific basis for the development of efficient and environmentally friendly insecticidal combinations and chemical control strategies targeting P. americana. Methods: Using feeding bioassay under laboratory conditions, the survival rates of P. americana exposed to 0.05% fipronil, 2.15% imidacloprid, 0.5% indoxacarb, and 0.5% dinotefuran gel baits, boric acid alone, and the combinations of boric acid with each of the four gel baits were determined. The median lethal time (LT50) and 95% lethal time (LT95) were calculated. One-way analysis of variance and the t-test were used to analyze intergroup differences. Results: Among boric acid and the four gel baits, significant differences were observed in their LT50 (F=73.750, P < 0.001) and LT95 (F=104.090, P < 0.001) for P. americana adults, in which fipronil exhibited the lowest LT50 [(30.12±4.90) h], while boric acid showed the lowest LT95 [(99.10±6.48) h]. The four combinations also showed significant differences in both LT50 (F=8.550, P=0.007) and LT95 (F=163.850, P < 0.001) for P. americana adults, in which boric acid plus imidacloprid yielded the lowest LT50 [(72.19±8.49) h], and boric acid plus fipronil had the lowest LT95 [(132.09±9.80) h]. Compared with imidacloprid alone, its combination with boric acid significantly reduced the LT50 against adult cockroaches (t=-251.500, P < 0.001). Fipronil combined with boric acid significantly increased the LT50 against adult cockroaches compared with fipronil alone (t=97.390, P < 0.001). For P. americana nymphs, the four combinations showed no significant difference in LT50 (F=0.400, P=0.760), but exhibited a significant difference in LT95 (F=9.280, P=0.006). Conclusions: All the combinations of boric acid with the four gel baits can enhance lethal efficacy against P. americana. Notably, the mixture of boric acid and fipronil provides the most effective long-term lethal effect.
Objective: To investigate the species composition, density distribution, and seasonality of flies in Zhangjiagang, Jiangsu Province, China, so as to provide evidence for developing scientific fly control strategies. Methods: Fly surveillance was conducted using the cage trap method at four types of habitats (farmers' markets, residential areas, outdoor catering environments, and green belts). The fly surveillance data of Zhangjiagang from 2014 to 2022 were organized and analyzed. With the use of SAS 9.4 software, mean comparison across multiple groups was conducted using randomized block analysis of variance, pairwise comparison of multiple means was performed using the Student-Newman-Keuls test, and annual trend analysis was conducted using generalized linear models. Results: A total of 1 728 flies were captured during the surveillance period, with an average density of 2.61 flies per cage. Flies identified belonged to 12 species of 8 genera in 3 families, with dominant species including Sarcophagidae flies, Muscina stabulans, Musca domestica, Lucilia sericata, and Aldrichina grahami. There was a difference in species composition across different years (F=8.501, P < 0.001), with the proportions of Sarcophagidae flies increasing from 23.73% in 2014 to 40.91% in 2022, and the proportion of Muscina stabulans increasing from 25.29% in 2017 to 35.80% in 2022. The proportion of Musca domestica decreased significantly from 42.37% in 2014 to 3.98% in 2022. The annual peak fly density occurred in 2017 (4.78 flies/cage), and the lowest density was recorded in 2014 (0.74 flies/cage). No significant difference in fly density was observed across different years (F=1.462, P=0.183). Seasonal fluctuation analysis revealed statistically significant differences in fly density across months (F=3.283, P=0.003). October was the peak month for fly density (6.39 flies/cage), followed by June and May. The difference in fly density across various habitats was statistically significant (F=12.452, P < 0.001). The annual average density across different habitats was as follows: farmers' markets (5.47 flies/cage) > residential areas (2.30 flies/cage) > green belts (1.53 flies/cage) > restaurant outdoor environments (1.43 flies/cage). Among these, Msa. domestica accounted for the highest proportion in farmers' markets (24.12%) and restaurant outdoor environments (32.13%), while Sarcophagidae flies dominated in green belts (40.34%) and residential areas (33.15%). Conclusions: The dominant fly populations have undergone significant changes, with Sarcophagidae flies and Msi. stabulans becoming the dominant species during 2020 to 2022 and Msa. domestica showing a greatly decreased proportion. October is the peak period for fly density throughout the year. Farmers' markets are key areas for fly control. Targeted control measures should be implemented based on species-specific population dynamics and habitat distribution patterns.
Objective: To investigate the density, seasonality, and breeding site characteristics of Aedes albopictus larvae in Yantian District, Shenzhen, China, so as to provide a scientific basis for dengue fever prevention and control. Methods: The surveillance data of Ae. albopictus larvae in Yantian District from 2020 to 2024 were collected. R 4.4.3 software was used for data analysis. The Kruskal-Wallis H test was used to compare the Breteau index (BI) across years and habitats. The Chi-square test was employed to compare habitat risk levels and the larval positivity rates of different breeding site types. The Fisher's exact test was used to compare the composition of positive breeding sites in different habitats. A seasonal autoregressive integrated moving average (SARIMA) model was constructed based on the biweekly time series data from 2020 to 2024. The prediction accuracy of the model was evaluated by comparing the observed and predicted values of January to May 2025. Larval density in June to December 2025 was forecasted. Results: The average BI in Yantian District from 2020 to 2024 was 2.36, showing an initial decline followed by an upward trend (H=47.126, P < 0.001). The BI differed significantly across habitats (H=151.210, P < 0.001), among which construction sites harbored the highest BI (3.55). The compliance rate of the BI was significantly different across habitats (χ2=35.677, P < 0.001), with construction sites having the lowest compliance rate (69.53%) and the highest proportion of medium and high density surveillance points (10.16%). Larval positivity rates differed significantly across different types of breeding sites (χ2=627.607, P < 0.001), with waste tires ranking first with a positivity rate of 34.38%. The composition ratio of positive breeding sites differed significantly in different habitats (P < 0.001). A SARIMA (0, 1, 2) (1, 1, 1)24 model was established, demonstrating good predictive performance (mean absolute error=0.698; root mean square error=0.802). The predicted peak period of the BI in 2025 was from the early half of July to the early half of September, with the highest value (5.09) expected in the early half of September. Conclusions: The density of Ae. albopictus larvae in Yantian District exhibits significant seasonality, and the risk of mosquito density is highest at construction sites among various habitats. It is recommended to enhance mosquito vector surveillance at construction sites during the active season of Aedes mosquitoes (May to October) and implement targeted breeding site management in construction areas, communities, schools, and parks. The BI in early half of September 2025 is estimated to exceed the safety threshold (BI > 5), indicating a risk of dengue transmission.
Objective: To analyze the ecological surveillance data of adult mosquitoes in Shanghai, China for their species composition and spatiotemporal distribution characteristics, so as to provide a basis for early warning of the risk of mosquitoes and mosquito-borne infectious diseases. Methods: The mosquito surveillance data by CO2-baited light trap method at various habitats across 16 districts in Shanghai were collected from 2017 to 2023. Python 3.11 software was used to conduct Chi-square tests on the composition of mosquito species in different years and habitats, and Friedman tests for multiple paired samples to analyze the monthly changes in mosquito density across different years, mosquito species, and habitats. ArcGIS Pro 3.0 software was employed for mapping. Results: Mosquito density in Shanghai from 2017 to 2023 was 4.86 mosquitoes/(lamp·night). Culex pipiens pallens, Aedes albopictus, Cx. tritaeniorhynchus, Armigeres subalbatus, and Anopheles sinensis accounted for 76.99%, 14.40%, 6.13%, 1.91%, and 0.57% of the total captures, respectively. Mosquito density showed a down-and-up trend. There was a significant difference in the composition of mosquito species in different years (χ2=6 300.543, P < 0.001). Schools, construction sites, and livestock sheds had the higher densities, which were 12.10, 11.46, and 8.30 mosquitoes/(lamp·night), respectively. The composition of mosquito species differed significantly in different habitats (χ2=26 258.065, P < 0.001). The peak period for mosquitoes was from late May to early September. Seasonal fluctuations in mosquito density differed significantly by year, species, and habitat (all P < 0.001). The average mosquito density varied greatly across different districts, with the highest levels in Xuhui District and the lowest levels in Changning District. Mosquito species composition varied greatly in different districts. The highest composition ratios were found in Yangpu District (89.29%) for Cx. pipiens pallens, in Jinshan District (33.06%) for Cx. tritaeniorhynchus, in Chongming District (7.17%) for Ar. subalbatus, in Jiading District (1.57%) for Anopheles sinensis, and in Huangpu District (57.16%) for Aedes albopictus. Conclusions: There are significant differences in mosquito density and species composition across different districts in Shanghai, suggesting that surveillance and control strategies should be developed according to local conditions. Mosquitoes are most active from late May to early September, during which mosquito control should be strengthened.
Objective: To identify the transmission chain, infection source, and risk factors of a cluster outbreak of psittacosis caused by continuous homogeneous exposure in Daxing District, Beijing, China, so as to provide a scientific basis for the prevention and control of psittacosis. Methods: An epidemiological investigation into five confirmed cases of psittacosis and their close contacts was conducted, and at the same time, environmental samples including parrots, cages, and feed from the parrot shop were collected for laboratory testing using real-time fluorescent quantitative PCR. Results: For the five cases [mean age, (59.40±11.59) years; 2 males and 3 females; mostly being retirees and farmers], the durations from exposure to onset of illness were relatively long, and they probably shared a common source of infection due to a definite history of exposure to parrots at the same parrot shop in a flower and bird market. Specifically, 3 cases had purchased parrots from the shop, 1 case had viewed parrots in the shop without making a purchase, and 1 case worked near the parrot shop. Following the outbreak, multiple environmental samples from the parrot shop tested positive. Conclusions: Continuous exposure at the parrot shop may have been the primary source of infection in this cluster outbreak in Daxing District, Beijing. The outbreak persisted for a long period, which was difficult to detect, highlighting the need to strengthen surveillance for psittacosis clusters and enhance multi-department collaboration to regulate market trade and management involving parrots and other birds.
Objective: To investigate the epidemiological characteristics and influencing factors of dengue fever in Jinghong, Xishuangbanna Dai Autonomous Prefecture, Yunnan Province, China in 2024, so as to provide a reference for the formulation of local dengue fever prevention and control measures. Methods: Descriptive epidemiological methods were used to analyze dengue fever epidemic data of Jinhong collected through the China Disease Prevention and Control Information System as well as epidemiological case investigation reports and vector surveillance data. The Mann-Whitney U test was employed to compare the distribution of two independent samples. The Kruskal-Wallis H test was used to compare the medians of multiple independent samples. The Chi-square test was used to compare categorical data. Spearman's rank correlation test was applied to analyze the correlation between non-normally distributed measurement data. Results: In 2024, Jinghong reported a total of 2 417 dengue fever cases, with an incidence rate of 360.82 per 100 000. Among these, there were 2 361 local cases, 48 cases imported from overseas, and 8 domestically transmitted cases. The peak period for case reporting was from August to November, with a total of 2 218 cases reported, accounting for 91.77% (2 218/2 417) of the total number. The number of local cases was positively correlated with the numbers of overseas-imported cases (ρ=0.919, P < 0.001) and domestically transmitted cases (ρ=0.778, P=0.003). Five sub-districts in the main urban area reported the highest number of cases (1 923, 79.56%). A positive correlation was observed between population density and the incidence rate of local cases (ρ=0.879, P < 0.001). The male-to-female ratio of the cases was 1.26∶1, with a statistically significant difference of incidence between the sexes (χ2=9.533, P=0.002). The sex ratio was 1.24∶1 for local cases and 3.00∶1 for overseas-imported cases, showing a statistically significant difference of the sex ratio of cases between different sources (χ2=7.388, P=0.007). The age of the cases was concentrated in 20 to < 60 years, with a median age [M(P25, P75)] of 41 (29.0, 54.0) years. The top three occupations of the cases were farmers (513 cases, 21.22%), homemakers and the unemployed (494 cases, 20.44%), and commercial service workers (310 cases, 12.83%). Occupational distribution differed between urban areas (sub-districts), towns, and farms. There were 174 cluster outbreaks involving 741 people, with a statistically significant difference in the number of cluster outbreaks between sub-districts (towns and farms) (H=26.833, P=0.003). The median time [M (P25, P75)] from onset to diagnosis was 2 (1.3, 2.4) days for local cases and 3 (1.2, 3.9) days for imported cases, with a statistically significant difference (Z=-2.526, P=0.012). In 2024, the average Breteau index in mosquito surveillance was 3.57, and the average net trapping index was 0.88 mosquitoes/(net∙h). A total of 1 341 female Aedes mosquitoes were captured in routine adult mosquito surveillance, including 540 Ae. aegypti mosquitoes (40.27%) and 801 Ae. albopictus mosquitoes (59.73%). Conclusions: The incidence of dengue fever in Jinghong shows apparent seasonality and clustering, which is affected by factors such as imported cases, urban population density, and Aedes mosquito density. It is necessary to continue to strengthen the key components of epidemic containment, improve the joint prevention and control mechanism, fully promote the implementation of community-based prevention and control strategies, and institutionalize regular epidemic management.
Objective: To analyze the temporal, spatial, and population-based epidemiological characteristics of Japanese encephalitis (JE) in Shanxi Province, China from 2004 to 2024, to provide references for JE prevention and control and policy formulation in the province. Methods: Descriptive epidemiological analyses were performed on the reported JE cases in Shanxi from the Chinese Disease Prevention and Control Information System. The trend in the incidence rates of JE among different populations was analyzed using the Chi-square test for trend. Results: A total of 993 cases of JE were reported in Shanxi Province from 2004 to 2024, with an average annual incidence of 0.14/100 000. The overall incidence of JE showed a downward trend. The cases were distributed across 99 counties (cities and districts) in Shanxi Province. The highest incidence rate was in Linyi County, with an average annual incidence rate of 1.42/100 000 and a total of 169 cases reported. Certain counties in Yuncheng and Jincheng of southern Shanxi Province were persistent hotspots for JE outbreaks. August was the peak month for the incidence of JE in Shanxi Province, with cases accounting for 55.99% (556/993) of the annual total number, followed by September (291/993, 29.31%). In the age groups of 0- < 15 years, 15- < 45 years, and ≥45 years, the proportions of cases were 6.14% (61/993), 20.04% (199/993), and 73.72% (732/993), respectively, and the average annual incidence rates were 0.07/100 000, 0.07/100 000, and 0.38/100 000, respectively. The proportion of reported cases ≥45 years of age accounted for within the annual incidence showed an upward trend (χtrend2=79.912, P < 0.001). The age group of 70- < 75 years had the highest incidence of JE, with an average incidence rate of 0.73/100 000. In terms of occupations, farmers constituted a higher proportion (769/993, 77.44%). Conclusions: While the overall incidence of JE in Shanxi Province shows a downward trend, periodic outbreaks persist in certain years. Certain counties of Yuncheng and Jincheng are key endemic areas for JE. Maintaining high JE immunization coverage among age-eligible children and strengthening JE prevention and control for adult populations should be prioritized.
Objective: To review the diagnostic process of a case of Bartonella henselae infection with a positive T cell spot test for tuberculosis infection (T-SPOT.TB), so as to provide a reference for improving the diagnostic accuracy of cat-scratch disease (CSD). Methods: In this case analysis, the clinical manifestations and the diagnostic and treatment process of the patient were described. Metagenomic next-generation sequencing (mNGS) and real-time quantitative PCR (qPCR) methods were employed for pathogen detection. An epidemiological investigation was performed to analyze the source of infection. In the patient's residential environment, vector surveillance was conducted using the sticky trap method. Results: The patient presented with systemic fatigue, accompanied by a mass in the left supraclavicular region exhibiting mixed echogenicity (suspicious for abscess) on superficial color Doppler ultrasonography. The T-SPOT.TB test was positive. Through ultrasound-guided puncture, fluid in the left supraclavicular mass was collected for mNGS and qPCR testing, both positive for Bartonella henselae [cycle threshold (Ct): 32.24]. The patient was ultimately diagnosed with CSD. After anti-infective treatment with doxycycline and symptomatic management, the patient fully recovered. Conclusion: The combination of mNGS with conventional diagnostic methods effectively improves the accuracy of diagnosing CSD, particularly for patients with positive T-SPOT.TB results in whom tuberculosis cannot be excluded, thereby preventing misdiagnosis as tuberculosis or other conditions.
Objective: To analyze the epidemiological characteristics of severe fever with thrombocytopenia syndrome (SFTS) in Hubei Province, China, so as to provide a scientific basis for the prevention and control of SFTS. Methods: In this retrospective study, the SFTS data of Hubei Province from 2014 to 2024 was obtained through the China Disease Prevention and Control Information System. A database of the SFTS data was established using Excel 2016 software. The demographic, temporal, and regional characteristics of SFTS were described using SPSS 25.0 software. Categorical data were described as percentages, and inter-group comparisons were performed using the Chi-square test. Univariable and multivariable logistic regression models were employed to analyze the risk factors for case fatality. With the use of ArcGIS 10.8, geographic distribution was mapped, and global and local spatial autocorrelation analyses were conducted. Using counties (cities and districts) as the smallest statistical units, the reported incidence rates were calculated and the spatial distribution characteristics were analyzed. Results: A total of 6 484 SFTS cases were reported in Hubei Province from 2014 to 2024, with an average annual incidence rate of 1.01/100 000. The annual incidence rate showed a significant upward trend (χ
Objective: To investigate the epidemiological features of severe fever with thrombocytopenia syndrome (SFTS) in Zhejiang Province, and analyze the impact of meteorological and geographical factors on the incidence of SFTS, so as to provide a basis for the scientific prevention and control of SFTS in Zhejiang Province. Methods: The data on SFTS cases, as well as meteorological and geographical factors in Zhejiang Province from January 1, 2018 to December 31, 2022 were collected. The basic epidemiological characteristics of SFTS were described. Boosted regression tree (BRT) model with different lag periods were constructed to determine the optimal lag period for new SFTS cases and explore the influencing factors for SFTS in Zhejiang Province. Results: The number of new cases of SFTS in Zhejiang Province from 2018 to 2022 was 404, including 221 males (54.70%) and 183 females (45.30%). Patients aged 60 to < 70 years accounted for the highest proportion (129, 31.93%), followed by the age group of 70 to < 80 years (118, 29.21%). Farmers were the most common occupation (125, 80.45%), The onset of the disease is concentrated from May to July. The BRT model exhibited the best performance when the optimal lag time was 2 weeks, with the area under the receiver operating characteristic curve was 0.918 for the training set and 0.783 for the test set. Average temperature and altitude contributed most to the risk of SFTS (21.64% and 20.27%, respectively). The analysis results of the BRT model indicated that the risk of SFTS was highest when altitude was in the range of 200-260 m; the risk of SFTS reached the highest level when average temperature rose to 23℃; and there was an interaction between average temperature and altitude, with a higher risk of SFTS when altitude was 0-320 m and average temperature was 20-25℃. The incidence of SFTS was facilitated when the slope was > 11°, the cumulative precipitation was > 150 mm, the normalized difference vegetation index was between 0.61 and 0.68, and the average air pressure was < 1 000 hPa; The impact of average wind speed on SFTS incidence showed an overall irregular fluctuation. Conclusions: The peak season for SFTS in Zhejiang Province occurs from late spring to early summer, and elderly farmers are the main population. The incidence of SFTS is greatly affected by average temperature and altitude. Therefore, it is necessary to carry out publicity and education for key populations and establish a system of early prediction and warning in low-altitude areas with appropriate temperature for preventing and controlling the incidence of SFTS.
Objective: To investigate the epidemic trend of hemorrhagic fever with renal syndrome (HFRS) in Hubei Province, China, and survey the distribution of host animal populations and their HFRS pathogen carriage status, so as to provide evidence for developing effective prevention and control strategies for HFRS. Methods: The cases and incidence of HFRS in Hubei were collected from National Disease Control and Prevention System for descriptive epidemiological analysis, while host animal surveillance data from 2021 to 2024 using the same methods. The correlation between the positive rate of Hantavirus in host animals and the incidence rate of HFRS was analyzed using Pearson correlation analysis. Results: The numbers of HFRS cases reported in Hubei Province from 2021 to 2024 were 436, 271, 174, and 135, respectively, adding up to 1 016, with an average annual incidence rate of 0.42/100 000. The cases were mainly distributed in Jingzhou, Xiangyang, Qianjiang, Tianmen and Jingmen cities. The incidence of HFRS occurred in every month, with the peak period in May to June (32.78%) and December to next January (21.16%). The male-to-female ratio was 2.65:1. The majority of the cases were middle-aged and elderly (≥40 years old, (853/1 016, 83.96%). The main occupation was farmers, accounting for 64.27% (653/1 016). A total of 6 507 rodents were captured from eight surveillance points across the province, with a Hantavirus positivity rate of 3.27% (213/6 507). The surveillance points with higher positivity rates included Xianning (67/803, 8.34%), Xiangyang (51/819, 6.23%), and Jingzhou (27/815, 3.31%). The rodent species with higher Hantavirus positivity rates were Rattus norvegicus (87/1 916, 4.54%) and Apodemus agrarius (72/2 049, 3.26%). The habitats with higher Hantavirus positivity rates were key industries such as catering (71/1 575, 4.51%) and farmland (94/2 310, 4.07%). Conclusions: The HFRS epidemic in Hubei Province was a downward trend from 2021 to 2024. Xianning, Xiangyang, and Jingzhou have a risk of HFRS outbreaks due to the high prevalence of hantaviruses in rodents. It is recommended to strengthen health education for middle-aged and elderly populations in rural areas and key cities, to reduce population exposure and infection risks through the construction of rodent-proof facilities and comprehensive rodent control methods, and to promote vaccination in key areas to reduce the risk of HFRS outbreaks.
Objective: To revise the catalogue of mammals and their distribution in the natural foci of plague in Sichuan Province, China, so as to provide the latest foundational data for research on zoonotic diseases in these areas. Methods: The mammal checklist was revised based on the mammalian data of field investigations in the natural plague foci of Sichuan Province, with reference to wildlife survey records during the recent three decades as well as the latest literature in these regions. Mammal species were documented by conservation status, distribution patterns, and other characteristics. Results: The presence of 81 mammal species of 51 genera in 22 families in 8 orders was confirmed in the natural foci of plague in Sichuan Province. Among them, there are 10 species of national class Ⅰ key protected wildlife and 20 species of national class Ⅱ key protected wildlife, and there are 22 species endemic to China and 1 species endemic to Sichuan Province. Compared with the Diversity of Mammals in Natural Foci of Plague in Sichuan Province (2023), distributions of 15 species such as Sorex minutissimus were removed, while distributions of 21 species such as Mustela eversmanii and Eospalax baileyi were added. According to the Plague Reservoirs and Their Classification in Natural Foci of China, 28 plague reservoirs have been identified. According to the Advances in Research on the Host Diversity in Plague Natural Foci in China, three main hosts have been identified. Conclusion: This mammal catalogue in the natural plague foci of Sichuan Province is based on the most recent international and domestic authoritative works and field sample verification and collection, providing the latest data for investigating zoonosis and studying transmission dynamics in the natural foci of plague in Sichuan Province.
Objective: To predict the distribution of Callopsylla dolabris in suitable habitats in China under different climate conditions by using the Maximum Entropy model (MaxEnt) combined with climate and geographical factors, to provide scientific basis for effective surveillance and prevention of this flea and related flea borne diseases in the northwest region of China. Methods: Distribution data of C. dolabris was collected from plague prevention and control professional institutions, and supplemented by searching the relevant distribution point information of the published literature in Chinese databases (China National Knowledge Infrastructure, Wanfang Data, VIP Database, etc.) and English databases (PubMed, Web of Science, etc.). RStudio 4.3.2 was used to process species distribution data and optimize model parameters. Based on species distribution data and environmental data, the optimized MaxEnt model was applied to predict and project the potential distribution of suitable habitats of C. dolabris in the current and future (80-year) periods. ArcGIS 10.8 software was employed to process environmental data and visualize prediction results. Results: The prediction results of the MaxEnt model showed that the area under the receiver operating characteristic curve was 0.933, indicating that the model had high accuracy. The three factors that contributed most to the model were altitude (contribution rate, 67.94%), annual average temperature (contribution rate, 11.75%), and annual precipitation (contribution rate, 6.25%). Based on the simulation results of future climate scenarios, the potential habitat area of C. dolabris shows an overall downward trend. In a specific ssp245 scenario, the distribution analysis of C. dolabris from 2041 to 2060 reveals the phenomenon of contraction and expansion in the suitable habitat areas, with the expansion areas mainly concentrated in Qinghai Province, Gansu Province, and the Xinjiang Uygur Autonomous Region. Conclusions: Altitude, temperature, and precipitation are the main factors affecting the distribution of C. dolabris. In the future, the area of suitable habitats for C. dolabris is expected to decrease on the whole, and climate change is unlikely to be a favorable factor for its growth and reproduction. The distribution of suitable habitats for C. dolabris is trending towards high-altitude areas in northwestern China.
Objective: To investigate the knowledge, attitudes, and practices (KAP) regarding dengue fever prevention and control among residents in Bao'an District, Shenzhen, China, and analyze its influencing factors, so as to provide a scientific basis for effective health education and publicity about dengue fever prevention and control among residents. Methods: Using an electronic questionnaire prepared on the Wenjuanxing platform with reference to relevant health industry standards and domestic and international literature, a cross-sectional survey was conducted by means of household survey and centralized survey methods among residents in Bao'an District from May to October 2024. The questionnaire data were organized and analyzed by using Excel 2019 and SPSS 27.0. The Chi-square test was used for univariate analysis of the pass rate, and unconditional logistic regression was used for multivariate analysis of the influencing factors. Results: For dengue fever prevention and control, the overall score percentage of KAP among 810 residents was 81.00% (42 648/52 650). Their knowledge awareness rate, attitude acceptance rate, and practice adoption rate were 76.26% (20 383/26 730), 85.13% (11 033/12 960), and 86.67% (11 232/12 960), respectively. Their pass rates for KAP were 70.62% (572/810), 83.70% (678/810), and 87.41% (708/810), respectively. The multivariable logistic regression analysis showed that age, education level, history of dengue fever, and access to dengue fever publicity and education significantly influenced residents' knowledge level of dengue fever prevention and control; and education level, marriage, history of dengue fever, and access to dengue fever publicity and education significantly influenced residents' practice in dengue fever prevention and control (all P < 0.05). Conclusions: Residents in Bao'an District have high levels of attitude acceptance and practice adoption in terms of dengue fever prevention and control, but their knowledge awareness needs to be further improved. Their knowledge and practice are influenced by factors such as age, education level, marriage, history of dengue fever, and access to dengue fever publicity and education. Targeted health education and promotion activities need to be carried out.
Objective: To establish an applicable detection system for pathogens carried by ticks intercepted at border ports, so as to provide technical support for port quarantine and the prevention and control of tick-borne diseases. Methods: The intercepted ticks were divided into six groups based on species, sex, and blood-sucking status. Their nucleic acids were extracted after grinding. Metagenomic next-generation sequencing (mNGS) was used for preliminary pathogen screening, followed by verification with targeted next-generation sequencing (tNGS), probe-based fluorescent quantitative PCR (qPCR), and traditional PCR (coventional PCR and nested PCR). Results: The intercepted ticks were identified as Dermacentor albipictus and Ixodes scapularis. By mNGS, Anaplasma phagocytophilum, Borrelia burgdorferi, Babesia microti, Yersinia enterocolitica, Rickettsia monacensis, R. amblyommatis, Ehrlichia minasensis, and Suffolk virus were detected in I. scapularis. By tNGS, the first four species of the mNGS results were detected. Probe-based qPCR detected the presence of A. phagocytophilum, Bo. burgdorferi, and Babesia. By traditional PCR, A. phagocytophilum, Bo. burgdorferi, Ba. microti, R. tamurae subsp. buchneri, and pathogenic Y. enterocolitica were positive, while Ehrlichia was negative. Finally, the identified pathogens carried by I. scapularis included A. phagocytophilum, Bo. burgdorferi, Ba. microti, R. tamurae subsp. buchneri, pathogenic Y. enterocolitica, and Suffolk virus. Conclusion: Border ports should establish a pathogen detection system based on mNGS screening and accurate verification with appropriate nucleic acid detection methods, so as to provide necessary technical support for the enforcement of health quarantine laws at frontier ports.
Objective: To investigate the distribution and antibiotic resistance of Yersinia enterocolitica isolated from samples of diverse sources in Lu'an, Anhui Province, China, so as to provide a scientific basis for the rational clinical application of antibiotics and the scientific prevention and control of Y. enterocolitica infections. Methods: From 2021 to 2023, various samples collected from different survey sites in Lu'an were subjected to isolation, culture, and antimicrobial susceptibility testing of Y. enterocolitica. Whole-genome sequencing was performed on some of the strains. The Chi-square test was used to compare the detection rates of different types of samples. Results: A total of 1 602 samples were collected from two surveillance sites in Lu'an from 2021 to 2023, including fecal samples from patients with diarrhea, animal fecal samples, and frozen/refrigerated foods from supermarkets. From them, 148 strains of Y. enterocolitica were isolated and cultured. The detection rate was highest in animal feces at 14.75% (73/495), followed by foods at 8.04% (27/336), and lowest in patients' feces at 6.23% (48/771). Ampicillin showed the highest resistance rate (49/106, 46.23%), followed by streptomycin (7/106, 6.60%). Multidrug-resistant bacteria accounted for 11.32% (12/106). Fifty-nine drug-resistant strains exhibited 14 distinct drug-resistant phenotypes. Strains isolated from patients with diarrhea and those from host animals each had 8 drug-resistant phenotypes (including 4 identical phenotypes between the two sources), and those from frozen/refrigerated foods had 3 drug-resistant phenotypes. Sequencing analysis of 23 human-derived strains revealed the presence of 10 resistance genes associated with 7 classes of antibacterial agents including β-lactams and aminoglycosides. However, discrepancies were found between the resistance gene carriage status and actual drug-resistant phenotypes of the strains. The core genome multilocus sequence typing results showed that among the 23 Y. enterocolitica strains, 16 cgST types were identified, with 4 strains of cgST150, and 3 strains each belonged to two unknown types. The whole genome single nucleotide polymorphism based phylogenetic tree of the strains indicated that they were divided into three major evolutionary clades, with no clustering of the strains observed. Conclusions: The detection rates of Y. enterocolitica vary in samples of different sources in Lu'an. Human-derived strains exhibit high genetic diversity with a scattered distribution. Antibiotic resistance characteristics differ between different hosts, but with a certain correlation between humans and animals. It is necessary to strengthen research on the drug resistance spectrum of Y. enterocolitica to provide a scientific basis for antibacterial therapy.
Objective: To investigate and compare the prevalence of Aedes albopictus larvae by two surveillance methods in Hongkou District, Shanghai, China over the past five years, and analyze the correlation between the two methods, so as to provide a reference for the optimizing surveillance, prevention, and control strategy of Ae. albopictus and dengue fever. Methods: From May to October each year of 2020 to 2024, the Breteau index (BI) method and the mosq-ovitrap method were used to monitor the density of Ae. albopictus larvae in eight sub-districts of Hongkou District. The surveillance results were subjected to comparative and correlation analyses. Excel 2021 was used for data collation and summary analysis, and SPSS 26.0 was used for statistical analysis. Analysis of variance was performed to compare mosquito density in different years and months. The Chi-square test was used to compare the the proportion of positive containers and mosq-ovitrap index (MOI) in different habitats. Pearson correlation analysis was conducted to study the correlation between the two surveillance methods. Results: The average BI values from 2020 to 2024 were 10.33, 5.69, 4.51, 6.39, and 5.68, respectively, and the differences were statistically significant (F=3.384, P=0.004). The BI in 2020 was higher than those in the other four years (all P < 0.05). The average MOI from 2020 to 2024 were 6.95, 6.58, 8.08, 11.81, and 9.32, respectively, with their differences being statistically significant (F=3.225, P=0.015). The MOI values in 2020 and 2021 differed significantly from that in 2023 (all P < 0.05). There were significant differences in the MOI at different times (F=2.487, P=0.019), with higher levels from early July to early September than in late May and early June (all P < 0.05). The BI in residential areas showed a fluctuating curve, while the BI in parks gradually increased since June and reached the highest level in early August. The MOI in residential areas and parks showed similar changing trends, peaking from late July to late August, during which the MOI in parks was higher than that in residential areas. The MOI was significantly different between residential areas and parks (χ2=11.971, P=0.001). The Pearson correlation analysis detected a significant correlation between the BI and the MOI (r=0.456, P=0.001). Conclusions: Mosquito density in Hongkou District peaks from early June to early September. There is a correlation between the results of the BI method and the MOI method.
Objective: To investigate the species composition of rodents and their pathogen carriage status in Suqian, Jiangsu Province, China, so as to provide a scientific basis for local rodent control and the prevention and control of rodent-borne diseases. Methods: The ecological surveillance of rodents was conducted using the night-snap trapping method in five counties/districts of Suqian. For rodent-borne pathogen surveillance, supplementary rodent specimens are collected based on the rodents captured via rodent ecological surveillance. The TaqMan probe-based qPCR or RT-qPCR method was then applied to detect the nucleic acids of 8 pathogens in rodent viscera, including pathogenic Leptospira, Rickettsia typhi, Anaplasma phagocytophilum, Bartonella, Orientia tsutsugamushi, Francisella tularensis, Hantavirus, and Dabie bandavirus. Data collation and analysis were performed using Excel 2019 and R 4.4. The Chi-square test and Fisher's exact test were applied to compare constituent ratios and rates. Results: From 2022 to 2023, the average rodent density in Suqian was 0.21% (47/22 251), and of the total captures, Rattus norvegicus accounted for 61.70% (29/47), and R. tanezumi and Mus musculus each accounted for 19.15% (9/47). There was a statistically significant difference in rodent density across different habitats (χ2=26.306, P < 0.001). A total of 435 rodents and shrews were captured for rodent-borne pathogen surveillance, among which 34 tested positive for the nucleic acids of the pathogens, with a positive rate of 7.82%. Specifically, 29 individuals (6.67%) were positive for pathogenic Leptospira, 16 (3.68%) for Bartonella, and 3 (0.69%) for Hantavirus. There was a statistically significant difference in the detection rates of the nucleic acids of different pathogens (χ2=24.244, P < 0.001). Thirteen Apodemus agrarius were co-infected with pathogenic Leptospira and Bartonella, one R. norvegicus was co-infected with pathogenic Leptospira and Hantavirus, and no other pathogens were detected. Conclusions: In 2022-2023, Suqian had a low rodent density, with R. norvegicus being the dominant species, and the nucleic acids of pathogenic Leptospira, Bartonella, and Hantavirus were detected, with a phenomenon of co-infection with two pathogens in rodents. To prevent the occurrence of rodent-borne diseases, it is necessary to actively implement comprehensive measures to reduce rodent density, and enhance residents' awareness of avoiding direct or indirect contact with rodents.
Spermophilus spp. are widely distributed in China, which carry a variety of pathogens and ectoparasites that can adversely affect human health. For the prevention and control of human epidemics caused by Spermophilus-related diseases, it is of great significance to have an understanding of research progress on the distribution of Spermophilus spp., pathogens carried by them and their ectoparasites, and molecular identification and phylogenetic relationships of Spermophilus spp. This review systematically presents the distribution characteristics of Spermophilus spp. in China and pathogens associated with these rodents and their ectoparasites. The impact of molecular identification technique on the prevention and control of Spermophilus-related diseases was evaluated in order to apply this technique to the research, surveillance, early warning, and control of Spermophilus spp.
