OBJECTIVE: To establish a surveillance and early warning index system for schistosomiasis transmission risk along the middle and lower reaches of the Yangtze River basin, so as to provide insights into creation of a sensitive and highly efficient surveillance and early warning system for schistosomiasis. METHODS: National and international publications, documents, laws and regulations pertaining to schistosomiasis control were retrieved with keywords including schistosomiasis, surveillance, early warning and control interventions from 2008 to 2022, and a thematic panel discussion was held to preliminarily construct surveillance and early warning index system for schistosomiasis transmission risk along the middle and lower reaches of the Yangtze River basin. The index system was then comprehensively scored and screened using the Delphi method, and the weight of each index was determined using analytic hierarchy process and the modified proportional allocation method. In addition, the credibility of the Delphi method was evaluated using positive coefficient, authority coefficient, degree of concentration and degree of coordination of experts. RESULTS: Following two rounds of expert consultation, a surveillance and early warning index system for schistosomiasis transmission risk in endemic areas along the middle and lower reaches of the Yangtze River basin was preliminarily constructed, including 3 primary indicators, 9 secondary indicators and 41 tertiary indicators. The normalized weights of primary indicators epidemics, natural and social factors and comprehensive control were 0.639 8, 0.145 6 and 0.214 6, respectively, and among all secondary indicators, snail status (0.321 3) and schistosomiasis prevalence (0.318 5) had the highest combined weights, while social factors had the lowest combined weight (0.030 4). Of all tertiary indicators, human egg-positive rate (0.041 9), number of acute schistosomiasis cases (0.041 5), number of stool-positive bovine and sheep (0.041 1), and prevalence of Schistosoma japonicum in free-ranging livestock (0.041 1) had the highest combined weights. During two rounds of consultation, the positive coefficient of experts was both 100%, and the authority coefficient was both 0.9 and greater, while the coordination coefficients were 0.338 to 0.441 and 0.426 to 0.565 (χ² = 22.875 to 216.524, both P values < 0.05). CONCLUSIONS The established surveillance and early warning index system for schistosomiasis transmission risk along the middle and lower reaches of the Yangtze River basin is of great scientific values and authority, which may provide insights into construction of the sensitive and highly efficient surveillance and early warning system for schistosomiasis in the context of low prevalence and low intensity of infection in China.
Animals ; Cattle ; Humans ; Sheep ; Rivers ; Schistosomiasis/prevention & control* ; Schistosoma japonicum ; China/epidemiology* ; Snails

Humans ; Water ; Rivers ; Skull/anatomy & histology* ; Brain/diagnostic imaging* ; Forensic Medicine ; Forensic Anthropology

Objective: To explore the changes in bacterial community structure, antibiotic resistance genome, and pathogen virulence genome in river water before and after the river flowing through Haikou City and their transmission and dispersal patterns and to reveal anthropogenic disturbance's effects on microorganisms and resistance genes in the aquatic environment. Methods: The Nandu River was divided into three study areas: the front, middle and rear sections from the upstream before it flowed through Haikou City to the estuary. Three sampling sites were selected in each area, and six copies of the sample were collected in parallel at each site and mixed for 3 L per sample. Microbial community structure, antibiotic resistance, virulence factors, and mobile genetic elements were analyzed through bioinformatic data obtained by metagenomic sequencing and full-length sequencing of 16S rRNA genes. Variations in the distribution of bacterial communities between samples and correlation of transmission patterns were analyzed by principal co-ordinates analysis, procrustes analysis, and Mantel test. Results: As the river flowed through Haikou City, microbes' alpha diversity gradually decreased. Among them, Proteobacteria dominates in the bacterial community in the front, middle, and rear sections, and the relative abundance of Proteobacteria in the middle and rear sections was higher than that in the front segment. The diversity and abundance of antibiotic resistance genes, virulence factors, and mobile genetic elements were all at low levels in the front section and all increased significantly after flow through Haikou City. At the same time, horizontal transmission mediated by mobile genetic elements played a more significant role in the spread of antibiotic-resistance genes and virulence factors. Conclusions: Urbanization significantly impacts river bacteria and the resistance genes, virulence factors, and mobile genetic elements they carry. The Nandu River in Haikou flows through the city, receiving antibiotic-resistant and pathogen-associated bacteria excreted by the population. In contrast, antibiotic-resistant genes and virulence factors are enriched in bacteria, which indicates a threat to environmental health and public health. Comparison of river microbiomes and antibiotic resistance genomes before and after flow through cities is a valuable early warning indicator for monitoring the spread of antibiotic resistance.
Humans ; Rivers ; Virulence Factors/genetics* ; RNA, Ribosomal, 16S/genetics* ; Microbiota/genetics* ; Anti-Bacterial Agents ; Drug Resistance, Microbial/genetics*

OBJECTIVE: To identify the spatial distribution pattern of Oncomelania hupensis spread in Hubei Province, so as to provide insights into precision O. hupensis snail control in the province. METHODS: Data pertaining to emerging and reemerging snails were collected from Hubei Province from 2020 to 2022 to build a spatial database of O. hupensis snail spread. The spatial clustering of O. hupensis snail spread was identified using global and local spatial autocorrelation analyses, and the hot spots of snail spread were identified using kernel density estimation. In addition, the correlation between environments with snail spread and the distance from the Yangtze River was evaluated using nearest-neighbor analysis and Spearman correlation analysis. RESULTS: O. hupensis snail spread mainly occurred along the Yangtze River and Jianghan Plain in Hubei Province from 2020 to 2022, with a total spread area of 4 320.63 hm², including 1 230.77 hm² emerging snail habitats and 3 089.87 hm² reemerging snail habitats. Global spatial autocorrelation analysis showed spatial autocorrelation in the O. hupensis snail spread in Hubei Province in 2020 and 2021, appearing a spatial clustering pattern (Moran's I = 0.003 593 and 0.060 973, both P values < 0.05), and the mean density of spread snails showed spatial aggregation in Hubei Province in 2020 (Moran's I = 0.512 856, P < 0.05). Local spatial autocorrelation analysis showed that the high-high clustering areas of spread snails were mainly distributed in 50 settings of 10 counties (districts) in Hubei Province from 2020 to 2022, and the high-high clustering areas of the mean density of spread snails were predominantly found in 219 snail habitats in four counties of Jiangling, Honghu, Yangxin and Gong'an. Kernel density estimation showed that there were high-, secondary high- and medium-density hot spots in snail spread areas in Hubei Province from 2020 to 2022, which were distributed in Jingzhou District, Wuxue District, Honghu County and Huangzhou District, respectively. There were high- and medium-density hot spots in the mean density of spread snails, which were located in Jiangling County, Honghu County and Yangxin County, respectively. In addition, the snail spread areas negatively correlated with the distance from the Yangtze River (r = -0.108 9, P < 0.05). CONCLUSIONS There was spatial clustering of O. hupensis snail spread in Hubei Province from 2020 to 2022. The monitoring and control of O. hupensis snails require to be reinforced in the clustering areas, notably in inner embankments to prevent reemerging schistosomiasis.
Animals ; Schistosomiasis/prevention & control* ; Spatial Analysis ; Ecosystem ; Gastropoda ; Rivers ; China/epidemiology*

OBJECTIVES: To study the relationship between water temperature and floating time of aquatic cadavers, providing a reference for more precise positioning and searching for floating corpses. METHODS: The floating model of guinea pig after drowning at 17-30 ℃ was established, and the floating times of carcasses were recorded. The collected data of 32 floating corpse cases in the Pearl River were sorted out and analyzed according to the floating time of corpses corresponding to each degree of water temperature. The relationship models between water temperature and the floating time of guinea pig carcass, and between that and the floating time of real cases were established. RESULTS: The floating time of the cadaver was negatively correlated with water temperature. The power function fitting equation of the relationship between floating time and water temperature of guinea pig carcass was y=1×10¹⁵x^-10.530(R²=0.871, P<0.01), and the power function fitting equation of the relationship between corpse floating time and water temperature was y=3×10⁶x^-3.467(R²=0.802, P<0.01). CONCLUSIONS It is found that average floating cadaver time has a power function with water temperature, which provides a reference for locating floating cadavers and establishing search models.
Animals ; Cadaver ; Drowning ; Guinea Pigs ; Postmortem Changes ; Rivers ; Temperature ; Water

OBJECTIVES: To establish a diatom database by analyzing the quatity, species distribution and differences of diatom in water samples of the whole navigable sections of the Beijing-Hangzhou Grand Canal, to provide a reference for the inference of the drowning site. METHODS: Water samples were collected at 22 sites in the navigable sections of the Beijing-Hangzhou Grand Canal (Jining section to Yangzhou Section), and the diatoms at each site were qualitatively and quantitatively analyzed by using graphite digestion-scanning electron microscopy. RESULTS: Sampling site T (Laohuaijiang River Line, Gaoyou City, Yangzhou City, Jiangsu Province) had the highest number of diatoms, while sampling site O (Siyang County, Suqian City, Jiangsu Province) had the lowest number of diatoms, with a large gap of 68 times. At sampling site Q (Jiangpu District, Huaian city, Jiangsu Province), there were 19 species of diatoms. The sampling site O had the least diatoms, with 7 species. There were no significant differences in species evenness and species diversity at each sampling site (P>0.05). Some sampling sites have characterized diatoms, such as Caloneis at station A (Taibai Lake, Weishan County, Shandong Province), Rhoicosphenia at station B (Nanyang Town, Weishan County, Shandong Province), Amphora at station I (Taierzhuang District, Zaozhuang City, Shandong Province) and Epithemia at station J (Pizhou 310 national highway, Xuzhou City, Jiangsu Province). CONCLUSIONS The species richness of diatoms gradually increased from north to south. Diatom species richness and species diversity might be higher in areas with complex environments and large population flow. Climate type has a certain influence on the distribution of diatoms.
Beijing ; Diatoms ; Drowning ; Humans ; Rivers ; Water

OBJECTIVES: To study the annual variation of diatoms in Zhangweixin River, to provide theoretical support by using diatom examination to estimate the time and place of the corpse entering water, and to establish a diatom database. METHODS: Samples were taken from 4 sampling sites in Decheng section of Zhangweixin River for 12 consecutive months. Non-metric multi-dimensional scaling (NMDS) analysis was performed on the species and content of diatom samples. Based on the sampling site of Tianqu Road, Sprensen similarity coefficient analysis was conducted with the data of other 3 sites in Decheng section and Leling section of Zhangweixin River and Ningjin section in previous studies. RESULTS: The number of diatom species was positively correlated with diatom content. The average diatom content in different months ranged from 1 054 to 13 041/10 mL, and the species composition ranged from 8 to 16, with differences in dominant species. The similarity coefficient of diatom species within 2 km were all higher than 0.956 52, which could not be distinguished effectively. The similarity coefficients of Leling section and Ningjin section were 0.736 84 and 0.588 24 respectively, which could be effectively distinguished. CONCLUSIONS The species and content of diatom vary in different months in Zhangweixin River, and the composition of diatom species is different in different basins, which can provide reference for estimating the time and place of the corpse entering water in the river.
Cadaver ; Diatoms ; Drowning/diagnosis* ; Humans ; Rivers ; Water

OBJECTIVE: To analyze the spatial-temporal distribution characteristics of Oncomelania hupensis snails in Anhui Province from 2011 to 2020, to provide insights into precision control of O. hupensis snails in Anhui Province. METHODS: O. hupensis snail distribution data were collected in Anhui Province from 2011 to 2020 and descriptively analyzed, including actual area of snail habitats, area of emerging snail habitats and area of Schistosoma japonicum-infected snails. The actual area of snail habitats and area of emerging snail habitats were subjected to spatial autocorrelation analysis, hotspot analysis, standard deviation ellipse analysis and space-time scanning analysis, and the clusters of snail distribution and settings at high risk of snail spread were identified in Anhui Province from 2011 to 2020. RESULTS: The actual area of snail habitats gradually decreased in Anhui Province from 2011 to 2020. The actual area of snail habitats were 26 238.85 hm² in Anhui Province in 2020, which were mainly distributed in marshland and lake regions. There was a large fluctuation in the area of emerging snail habitats in Anhui Province during the period from 2011 to 2020, with the largest area seen in 2016 (1 287.65 hm²), and 1.96 hm² emerging infected snail habitats were detected in Guichi District, Chizhou City in 2020. Spatial autocorrelation and hotspot analyses showed spatial clusters in the distribution of actual areas of snail habitats in Anhui Province from 2011 to 2020 (Z = 3.00 to 3.43, all P values < 0.01), and the hotspots were mainly concentrated in the marshland and lake regions and distributed along the south side of the Yangtze River, while the cold spots were mainly concentrated in the mountainous regions of southern Anhui Province. There were no overall spatial clusters in the distribution of areas of emerging snail habitats (Z = -2.20 to 1.71, all P values > 0.05), and a scattered distribution was found in local regions. Standard deviation ellipse analysis showed relatively stable distributions of the actual areas of snail habitats in Anhui Province from 2011 to 2020, which was consistent with the flow direction of the Yangtze River, and the focus of the distribution of areas of emerging snail habitats shifted from the lower reaches to upper reaches of Anhui section of the Yangtze River. Space-time scanning analysis identified two high-value clusters in the distribution of actual areas of snail habitats in lower and middle reaches of Anhui section of the Yangtze River from 2011 to 2020, and two high-value clusters in the distribution of areas of emerging snail habitats were identified in mountainous and hilly regions. CONCLUSIONS There were spatial clusters in the distribution of O. hupensis snails in Anhui Province from 2011 to 2020, which appeared a tendency of aggregation towards the south side and upper reaches of the Yangtze River; however, the spread of O. hupensis snails could not be neglected in mountainous and hilly regions. Monitoring of emerging snail habitats should be reinforced in mountainous and hilly regions and along the Yangtze River basin.
Animals ; China/epidemiology* ; Ecosystem ; Gastropoda ; Lakes ; Rivers ; Schistosoma japonicum

Gansu province is located at the intersection of the three plateaus(Qinghai-Tibet Plateau, Inner Mongolia Plateau, and Loess Plateau) and the three river basins(Yellow River Basin, Yangtze River Basin, and inland river basin). The complex eco-environment and climate conditions here have created rich and diverse vegetation. Therefore, it is of great significance to study the spatial distribution characteristics of rare and endangered medicinal plant resources in Gansu province for formulating reasonable protection po-licies and promoting the development of medicinal plant industry. The data of rare and endangered medicinal plant resources in 87 counties of Gansu province were collected from results of the fourth general survey. The spatial distribution and the high-or low-value gathering area of rare and endangered medicinal plant resources in Gansu province were analyzed by geostatistical methods such as exploratory spatial data analysis, trend surface analysis, and Anselin Local Moran's I. The eco-environment characteristics of the high-or low-value gathering area were analyzed with the data of vegetation type, soil texture classification, annual mean temperature, annual mean precipitation, and elevation. Furthermore, the relationships of the spatial distribution and diversity with the geographical environment of rare and endangered medicinal plants in Gansu province were analyzed to provide support for the restoration and protection policy making of these plant resources.
China ; Plants, Medicinal ; Rivers ; Soil ; Tibet

Objective: To analyze the epidemiological characteristics of pulmonary tuberculosis (TB) in Guangdong province from 2016 to 2020 and provide evidence for the prevention and control of pulmonary TB. Methods: Descriptive epidemiological methods were used to analyze the incidence data of pulmonary TB reported in Guangdong from 2016 to 2020. Dynamic geometric series averaging and circular distribution methods were used to reveal the epidemic pattern. Results: A total of 356 748 pulmonary TB cases were reported in Guangdong from 2016 to 2020. The reported incidence of pulmonary TB decreased from 71.82/100 000 to 50.40/100 000 (trend χ²=6 905.57,P<0.001) , with an annual decline rate of 8.47%. Results from the circular distribution methods showed that the incidence peak would occur on May 4^th-5^th (Z=1 176.96,P<0.05), and the incidence was relatively higher in May compared with other months. The area distribution of the pulmonary TB epidemic was uneven, and the reported average annual incidence was in the order of the eastern area (72.15/100 000), the northern area (68.14/100 000), the western area (65.31/100 000) and the Pearl River Delta area (60.05/100 000). Results of dynamic geometric series averaging analysis showed a declining trend in the reported incidence of pulmonary TB in all areas, except Dongguan, with the average growth rate less than 0.00. The decline rate in the eastern area (-10.90%) and northern area (-10.63%) was higher than the provincial average (-8.47%). The male to female ratio of the cases was 2.63∶1 (258 562∶98 186). The reported average annual pulmonary TB incidence in men (88.37/100 000) was higher than that in women (36.86/100 000), the difference was significant (χ²=75.19, P<0.001). The reported incidence of pulmonary TB generally increased with age (trendχ²=123 849.44, P<0.001), and reached peak in age group ≥65 years (164.54/100 000). Dynamic geometric series averaging analysis showed an increasing trend of the reported pulmonary TB incidence in age groups 5-14 years and 15-24 years, with the average growth rate of 0.05% and 3.60%. Conclusions: The reported annual incidence of pulmonary TB showed a declining trend year by year in Guangdong from 2016 to 2020. However, an increasing incidence was reported in children and adolescents. Active case finding should be strengthened in the elderly and other key populations. With comprehensive TB prevention and control measures, it is still necessary to pay attention to the prevention and control of pulmonary TB in men, low-income groups and less developed areas in Guangdong and strengthen the comprehensive prevention and control in winter and spring.
Adolescent ; Child ; Aged ; Female ; Humans ; Male ; Child, Preschool ; Tuberculosis, Pulmonary/epidemiology* ; Epidemics ; Poverty ; Rivers ; China/epidemiology*