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  • ZHANG Ao-kun, CHEN Long-fei, LI Jing, YUAN Hui-zhen, LI Sen-yang, JIAN Fu-chun
    Objective To compare the efficacy of five Blastocystis staining method for staining cells with different morphologies and in different developmental stages to select appropriate staining techniques for specific scenarios and experimental purposes. Methods Blastocystis was stained using Wright-Giemsa, periodic acid-Schiff (PAS), Oil Red O, Nile Red, and Lugol's iodine solution respectively. The staining effects of the five method on Blastocystis were compared. Results Wright-Giemsa staining colored the cytoplasm and nucleus of Blastocystis bluish-purple, with other parts lightly stained; PAS staining rendered Blastocystis cells red; Oil Red O staining showed different structures within Blastocystis in varying intensities of orange-red; Nile Red enabled Blastocystis to fluoresce orange-yellow under a fluorescence microscope; Lugol's iodine solution stained the cytoplasm and nucleus a dark brownish-yellow. Conclusions Wright-Giemsa staining is recommended for clinical diagnosis. For metabolic studies, a combination of periodic acid-Schiff (PAS) staining and Oil Red O staining is suggested; PAS + Oil Red O staining can provide comprehensive morphological evidence for cell metabolism research. Nile Red staining is recommended for dynamic observation of live Blastocystis. Lugol's iodine staining is suitable for preliminary screening of large-scale samples.
  • LIANG Jing, XUE Zhi-qiang, LI Xue-bing, WU Di, WANG Han
    Objective To investigate changes in the distribution of Oncomelania hupensis snails in Yixing City, Jiangsu Province, from 2008 to 2024, and to provide insights to guide formulation of O. hupensis snail investigation and surveillance programs. Methods Data from O. hupensis snail surveys in Yixing City from 2008 to 2024 were collected. Trends in snail habitat site numbers, snail-infested areas,proportion of total area with snail habitats, occurrence of frames with living snails, and density of living snails in snail habitats in hilly regions of Yixing City were evaluated from 2008 to 2024 by applying a Joinpoint regression model to collect annual percent change (APC) and average annual percent change (AAPC) data. Results From 2008 to 2024, a total of 193.815 hm2 of snail-infested area was found within Yixing City, of which 191.765 hm2 (accounting for 98.94%) was distributed in hilly regions. A total of 344 snail infestation sites in hilly regions were identified. The average occurrence rate of living snail frames in snail habitats was 8.650% and the average living snail density in snail habitats was 0.246 per 0.1 m2. No Oncomelania snails were positively identified. The number of snail habitat sites in hilly regions of Yixing City showed no significant decreasing trend (AAPC=-2.8%, P=0.527). Similarly, no significant increasing trend in snail-infested area (APC=AAPC=5.7%, P=0.328) was found. The occurrence rate of living snail frames in snail habitats showed no significant increasing trend (APC=AAPC=5.1%, P=0.583). Living snail density in snail habitats also showed no significant increasing trend (APC=AAPC=3.2%, P=0.598). Conclusions From 2008 to 2024, snail infestation has persisted in the hilly areas of Yixing City with an unclear variation trend. The quality of snail investigation and snail surveillance system should be strengthened to permit timely identification of hidden dangers and rapid risk responses, thereby preventing schistosomiasis outbreaks.
  • WANG Dun-jia, HE Xiao-lu, ZHANG Tian-tian, WANG Tang, DONG Zhao-peng, SONG Can-lei, TAO Shi-ji, HOU Zheng-xing, CHENG Yu-ping, ZHOU Yi-bin
    Objective The aim of the study is to analyze the incidence patterns and epidemiological characteristics of parasitic and vector-borne diseases in the Minhang and Jinshan districts of Shanghai, and provide evidence-based information for optimizing prevention and control measures. Methods We collected information from epidemic reports and epidemiological investigation forms for cases of parasitic and vector-borne diseases from 2005 to 2024 in Shanghai's Minhang and Jinshan districts. Descriptive epidemiological method were adopted to conduct a comparative analysis of incidence trends, epidemic characteristics, and infection sources. Results A total of 229 cases in 7 categories were reported between 2005 and 2024, with an average annual incidence rate of 0.36/100 000. The average annual incidence rate in Minhang District was significantly higher than that in Jinshan District. The most prevalent diseases were malaria and dengue fever, followed by Japanese encephalitis. Monthly case reports were available, predominantly from June to October, with a peak in July-August. A statistically significant difference was observed between the two districts in case distribution during June-October (P<0.001), whereas no significant difference was found for July-August (P=0.331). The majority of cases were young men (111/229, 48.47%), aged 20-39 years. Migrant workers/farmers constituted the largest occupational group (55/229, 24.02%). Registered residents of other provinces and cities (147/229, 64.19%), and the main source of infection was overseas importation (112/229, 48.91%). There were no statistically significant differences in gender and household-registration composition between the two districts (P>0.05). Significant differences existed in age, occupation, and source of infection (P<0.05). The imported diseases were malaria and dengue fever, with Africa and Southeast Asia being the primary source locations. Malaria was the predominant disease imported from other provinces and cities, with cases having been imported from abroad since 2012. Local infections were mainly Japanese encephalitis, followed by malaria (with the last local case reported in 2010). Cases between 2005 and 2009 were predominantly imported from other provinces and cities. The proportion of cases imported from abroad increased sharply after 2010, particularly in Minhang District. Local infections sometimes arise in Jinshan District, with Japanese encephalitis serving as the primary type. Conclusions Incidence rates of parasitic and vector-borne diseases in Minhang and Jinshan districts have generally remained low. To further reduce this disease burden, it will be necessary to strengthen joint measures for prevention and control, eliminate the environmental risk factors of vector organisms, enhance monitoring and precise control of the environment and inbound personnel to prevent the occurrence and transmission of parasitic and vector-borne diseases.
  • MENG Yan, YANG Yang, YANG Xiao-xing, YANG Jun-yong, DU Ruo-yi, TIAN Li-na, LI Ruo-xi, LIN Gui-yin, RUAN Xiao-li, ZHANG Jian-jun, XIN Zhen-jiang, TIAN Li-li
    Objective We reviewed and analyzed the epidemiological data of 83 imported dengue fever cases reported in Fengtai District, Beijing, from 2007 to 2025, to delineate their epidemiological characteristics and guide the dengue fever prevention and control strategy in the future. Methods Data on dengue fever cases in Fengtai District from 2007 to 2025 were collected to identify the epidemic factors and characteristics using descriptive epidemiological method. Results All 83 dengue fever cases reported in this region over the past two decades have been imported from abroad or other domestic areas, with Southeast Asian countries being identified as the primary source of imported infections, accounting for 42 cases (50.60%), followed by 15 cases (18.07%) from Chinese provinces other than Beijing. The remaining import sources included 13 cases from South Asia, 8 from African countries, and each from Oceania, South America, and Europe. Disease onset was found concentrated between May and November. The sex ratio (male-to-female) is 1.59∶1. The age of onset ranged from 14 to 61 years old, with a median age of 36. The largest proportion of cases was observed among cadres and office workers (31 cases, 37.35%), followed by businessmen (13 cases, 15.67%), and householders or the unemployed (10 cases, 12.05%). Travel visit was identified as the primary reason for their exposure history. Conclusions All dengue fever cases reported in Fengtai from 2007 to 2025 were imported, with an increasing trend of imported cases in Beijing originating from other Chinese provinces. It is essential to strengthen health education for foreign travelers and returning residents, enhance clinical diagnosis and treatment training for medical personnel, eliminate mosquito breeding sites, and reduce mosquito density through active patriotic health campaigns.
  • GAO Jian, CHEN Hong-na, WU Zhi-ming, YANG Wei-fang, CHU Hong-liang
    Objective To analyze mosquito species composition and prevalence of pathogens carried by mosquitoes in Jiangsu Province from 2020 to 2024 and to provide a scientific basis for the prevention and control of mosquito-borne diseases. Methods Mosquitoes were collected using CO2-baited traps. The presence of mosquito-borne pathogens including dengue virus, Japanese encephalitis virus, yellow fever virus, West Nile virus, Chikungunya virus, and Sindbis virus was tested using commercial kits for fluorescence-based quantitative PCR. Results The most prevalent mosquito species found across different regions of Jiangsu Province were Culex pipiens pallens and Cx. tritaeniorhynchus, accounting for 81.35% to 93.01% of the total, followed by Armigeres subalbatus and Anopheles sinensis, which comprised 5.89% to 15.85% of the total. The densities of other monitored mosquito species were relatively low. Pathogen detection revealed that, only Cx. tritaeniorhynchus tested positive for Japanese encephalitis virus nucleic acid, whereas the remaining four mosquito species tested negative for the nucleic acids of all other six pathogens. The overall positivity rate of Japanese encephalitis virus (JEV) in Cx. tritaeniorhynchus showed an initially increasing trend followed by a decrease and a subsequent increase. The peak detection rate occurred in 2021(11.93%), with a much lower positive rate of 0.80% in 2023. Genotyping result revealed that all JEV strains in Jiangsu Province belonged to the G1 genotype and were genetically closest to the strain Shangdong08DY.29 (MN072875.1). Conclusions The incidence of Japanese encephalitis virus carried by mosquito, especially Cx. tritaeniorhynchus, in Jiangsu Province shows an upward trend, requiring sustained surveillance. A variety of monitoring method should be adopted to survey mosquitoes across different habitats, ensuring the accuracy and comprehensiveness of the monitoring result.
  • WU Zhi-ming, TIAN Ye, YANG Wei-fang, CHEN Hong-na, GAO Jian, LIU Hui, ZHANG Yu-fu, CAO Gan, CHU Hong-liang
    Objective To investigate the species composition, distribution, density, and pathogen-carrying status of host-seeking ticks in urban environments of Jiangsu Province, and to provide a scientific basis for the prevention and control of tick-borne diseases in urban settings. Methods From April to September 2023, a survey on host-seeking ticks was conducted in three types of habitats (city parks, residential areas, and street greenbelts) across 54 counties (cities, districts) of 13 prefecture-level cities in Jiangsu Province by using the flagging method. RStudio 4.4.3 (Windows version) was employed to perform chi-square test analysis on the species composition of ticks across different months, and Friedman test (for multiple paired samples) was applied to analyze monthly changes in the average tick density index among different habitats. Quantitative real-time PCR was performed to detect pathogens in the captured ticks. Results A total of 863 host-seeking ticks were captured from 54 habitats in 24 counties (cities, districts) of 11 prefecture-level cities (Nanjing, Wuxi, Changzhou, Suzhou, Nantong, Huai'an, Yancheng, Yangzhou, Zhenjiang, Taizhou, and Suqian) in Jiangsu Province, whereas no ticks were captured in Xuzhou and Lianyungang. The collected ticks belonged to three species, with Haemaphysalis longicornis being the dominant species (accounting for 82.62%), followed by Haemaphysalis flava and Hae. phasiana. The average density index of ticks in positive habitats was 3.20 ticks/(flag·100 m). In terms of tick density among prefecture-level cities, Wuxi had the highest density[13.55 ticks/(flag·100 m)], whereas Nanjing and Taizhou had the lowest[both, 0.20 ticks/(flag·100 m)]. With respect to the types of positive habitats, 46 positive city parks, 7 positive residential areas, and 1 positive street greenbelt were found, with the average tick density index being 3.46, 1.86, and 3.60 ticks/flag·100 m, respectively. No statistically significant differences were observed in the monthly variations in the average tick density index among different habitats (P > 0.05). Pathogen detection showed no Bandavirus dabieense, Rickettsia, or Borrelia burgdorferi in the collected ticks. Conclusions Host-seeking ticks have established populations in urban environments across most prefecture-level cities in Jiangsu Province, with Hae. longicornis identified as the dominant species. City parks serve as the primary breeding habitats for these ticks. Strengthening tick surveillance and control measures in densely populated and frequently visited areas, such as city parks and residential neighborhoods, is crucial for the effective prevention and control of urban tick-borne diseases.
  • WEI Ya-nan, XU Tong, MI Su, ZHANG Rong-qiang, LIU Fu-rong, XIN Hao-lin, FU Yi-yue, MA De-zhen
    Objective To understand the distribution, species composition, seasonal fluctuations, and presence of Dabie bandavirus in ticks in Tai'an City, providing a basis for assessing tick-borne disease risks and formulating prevention strategies. Methods Free-living ticks were monitored using the flagging method, whereas parasitic ticks were monitored through host surface examination. Reverse transcription-polymerase chain reaction (RT-qPCR) was used to detect the presence of Bandavirus dabieense in tick specimens. Results The density of free-living ticks in Tai'an City showed a continuous decreasing trend over the 3 years from 2021 to 2023, with an average tick density of 0.43 ticks/(flag·100 m). The dominant habitats were scenic areas and forests, and the seasonal fluctuations exhibited a bimodal pattern, peaking in March and August. The only free-living tick species captured was Haemaphysalis longicornis. Over the 3 years, the average tick index for parasitic ticks was 1.85, with sheep as the primary host. Seasonal fluctuations also followed a bimodal pattern, peaking in March and August. The primary parasitic tick species captured were H. longicornis and Rhipicephalus sanguineus. No Dabie bandavirus was detected in the tick specimens. Conclusions Tick density in Tai'an City remains relatively high, necessitating continued efforts to enhance tick surveillance and implement targeted prevention measures in rural environments to further reduce the health risks posed by tick-borne diseases.
  • LIU Zheng-xiang, SHAO Zong-ti, LI Yu-qiong, YUAN qing-hong
    Objective To characterize the species composition and distribution patterns of ticks in 17 counties and cities of Yunnan Province, thereby furnishing fundamental data for the prediction, prevention, and control of local tick-borne diseases. Methods Tick specimens deposited in Yunnan Institute of Endemic Disease Control and Prevention (YIEDC) collected from 17 counties or cities during 1957-2024 were thoroughly trimmed andmorphological identified based on diagnostic characters. Results A total of 2 923 tick specimens were taxonomically identified and classified into 18 species within 6 genera in the Ixodidae family. Specifically, the genus Haemaphysalis comprised 6 species with 154 specimens, the genus Rhipicephalus included 3 species with 2 444 specimens, the genus Ixodes consisted of 4 species with 236 specimens, the genus Amblyomma included 3 species with 49 specimens, the genus Dermacentor contained 1 species with 12 specimens, and the genus Hyalomma included 1 species with 28 specimens. A wide range of host animals were found, including livestock, wild avian species, wild mammalian species, reptiles (including pythons), and humans. Conclusions Ticks were found on a wide array of host animals within the 17 counties and cities of Yunnan Province, demonstrating high host species diversity. Our data suggest a need to strengthen the monitoring of tick-borne diseases and provide health education for the general population in Yunnan Province.
  • XIA Jian-jun, ZHOU Pu-min, ZHANG Yan, SONG Bing-dong, SUN Lu-yao, ZHANG Shou-gang
    Objective Using cockroach surveillance data in Nanjing from 2017 to 2024, we have descriptively analyzed population characteristics and changes in insecticide resistance among Blattella germanica, and have established a seasonal Autoregressive Integrated Moving Average (ARIMA) model to predict monthly population densities in Nanjing spanning the year 2025. Methods B. germanica density and infestation rate were monitored using the sticky trap method, and insecticide resistance was assessed using the residual contact method. Our ARIMA model was applied to fit and estimate cockroach density fluctuations over time. Results From 2017 to 2024, B. germanica accounted for 94.90% of all cockroach specimens captured in Nanjing, with an average density of 0.37 cockroaches per trap and an average infestation rate of 5.56%. Significant differences in density and infestation rate were observed among different habitats (P<0.001). Significant downward annual trends in both density and infestation rate were found (P<0.05). ARIMA was found to be the optimal model for fitting the density data from 2017 to 2024 (0,1,1)×(0,1,1)12. Conclusions From 2017 to 2024, B. germanica was overwhelmingly the dominant cockroach species in Nanjing, with both its density and infestation rate declining annually. A positive correlation was observed between the amount and proportion of insecticide use and the development of insecticide resistance (P<0.05). The established model demonstrated good performance in predicting monthly B. germanica densities in Nanjing throughout 2025, providing a valuable reference for future surveillance and control efforts.
  • LAI Yun-yan, GUAN Cai-ling, WU Ying-hua, ZHU Jian
    Objective In this study, the resistance of Blattella germanica to D-cyphenothrin in Guangdong Province was analyzed. Further, the contact activity of eight types of plant essential oils against B. germanica and their synergistic effects with D-cyphenothrin were tested and screened, providing a basis for slowing down insecticide resistance in pests and developing plant synergists. Methods The drip test method was used to measure the resistance levels of B. germanica to D-cyphenothrin in four cities of Guangdong Province: Zhongshan City, Foshan City, Zhuhai City, and Jiangmen City. In addition, the contact killing activities of eight types of plant essential oils against B. germanica, namely, garlic, cinnamon, clove, camphor, eucalyptus leaves, tea tree,Angelica dahurica and peppermint, and their synergistic activities with D-cyphenothrin were evaluated. Results Except for B. germanica in the Xiaolan area of Zhongshan, which was moderately resistant, B. germanica in the other four towns in Guangdong were all highly resistant. Among the eight essential oils tested, garlic essential oil had the strongest toxic activity against B. germanica, with LD50 values of 45.01 μg/individual. A concentration of 2% essential oil plus D-cyphenothrin (LD20) was used to screen for synergistic activity. After 24 h of treatment, Angelica dahurica, garlic, peppermint, camphor, and tea tree essential oils showed synergistic activity. Of these, A. dahurica essential oil had the strongest synergistic activity, with a synergistic coefficient of 125%. Conclusions The essential oil of garlic had the strongest toxic activity against B. germanica, and the essential oils of A. dahurica and garlic together had the strongest synergistic activity with D-cyphenothrin, thereby providing a reference for developing natural plant synergists.
  • Case report

  • ZHOU Xu-wei, CHENG Wei-jia
    This study reports a case of hydatidosis in a 27-year-old male from Suizhou, Hubei Province, a long-time resident of Wuhan. The patient visited the hospital for treatment of upper abdominal pain. CT tomography revealed a large cystic lesion in the left lobe of the liver. Hydatidosis was confirmed based on morphology. High-throughput sequencing analysis of the pathogenic microbial nucleic acids indicated that the pathogen was Echinococcus canadensis. The patient recovered and was discharged after cyst resection.
  • Review

  • DENG Jie, ZHU Xiao-tong
    Malaria is one of the three major infectious diseases posing a serious threat to human health worldwide. Microtubules and actin in Plasmodium are the main components of its cytoskeleton and play a crucial role in parasitic development, division, and invasion. Plasmodium cytoskeleton proteins exhibit significant differences from canonical cytoskeleton proteins, making them potential targets for antimalarial drugs. This review focuses on recent advancements in the study of microtubules and actin within the Plasmodium cytoskeleton, aiming to provide a reference for antimalarial drug research and development.
  • HE Qiu-yue, LIU Xiao-he, JIANG Jia-fu
    Mosquito-borne diseases pose a major threat to global public health. The gut microbiota colonizing the mosquito intestinal tract plays a critical role in regulating pathogen infection, replication, and transmission. This review summarizes the effects of mosquito gut microbiota on the transmission potential of mosquito-borne pathogens, explores the interaction mechanisms between gut microbial communities and pathogens, and discusses the potential of microbiome-based strategies to reduce mosquito-borne disease transmission.