中国血吸虫病防治杂志最新文献

Objective: To compare the external morphological characteristics and movement patterns between Schistosoma japonicum and S. sinensis cercariae.

Methods: S. japonicum and S. sinensis cercariae were heat-fixed, and well-extended cercariae, of 50 each species, were randomly selected for measurement of body length, body width, tail stem length, and tail fork length. The external morphological characteristics of S. japonicum and S. sinensis cercariae were compared. In addition, S. japonicum-infected Oncomelania snails and S. sinensis-infected Tricula snails were observed under a microscope and the movement patterns of S. japonicum and S. sinensis cercariae were compared.

Results: The mean body length, body width, tail stem length, and tail fork length were (0.16 ± 0.01), (0.05 ± 0.01), (0.14 ± 0.01) mm and (0.06 ± 0.01) mm for S. japonicum cercariae, and (0.13 ± 0.01), (0.05 ± 0.01), (0.13 ± 0.01) mm and (0.06 ± 0.01) mm for S. sinensis cercariae, respectively, and there were significant differences in terms of cercaria body length (t = 14.583, P < 0.05) and tail stem length (t = 3.861, P < 0.05), while no significant differences were seen in terms of body width (t = 0.896, P > 0.05) or tail fork length (t = -0.454, P > 0.05). Microscopy revealed that the tails of both S. japonicum and S. sinensis cercariae swung from side to side and there was no significant difference in their movement pattern.

Conclusions: S. sinensis and S. japonicum cercariae share highly similar external external morphological characteristics and movement patterns.

Plasmodium falciparum malaria, caused by Plasmodium falciparum infection, is an Anopheles mosquito-transmitted infectious diseases, which predominantly occurs in tropical areas of Africa. P. falciparum malaria is characterized by complex and atypical clinical manifestations, and high likelihood of misdiagnosis and missing diagnosis, and may be life-threatening if treated untimely. This case report presents the diagnosis and treatment of a P. falciparum malaria case with acute abdominal pain as the first symptom.

Objective: To analyze the epidemiological characteristics of leptospirosis in China from 2010 to 2022, so as to provide insights into formulation of the leptospirosis control strategy.

Methods: All data pertaining to clinically diagnosed cases and confirmed cases of leptospirosis reported in China from January 1, 2010 to December 31, 2022 was collected from Chinese Disease Prevention and Control Information Management System. The spatial, temporal and population distributions, and report and diagnosis institutions of leptospirosis cases were analyzed using a descriptive epidemiological method.

Results: A total of 4 559 leptospirosis cases were reported in China from 2010 to 2022, with an annual average number of 351 cases, and the number of reported leptospirosis cases reduced from 679 cases in 2010 to 158 cases in 2018. A total of 4 276 leptospirosis cases were reported in Sichuan Province, Yunnan Province, Guangdong Province, Hunan Province, Fujian Province, Zhejiang Province, Guangxi Zhuang Autonomous Region, Anhui Province, Jiangxi Province and Guizhou Province, accounting for 93.79% of the total number of leptospirosis cases in China. The number of leptospirosis cases had recently appeared a remarkable decline in Yunnan Province, while a significant rise was seen in the number of leptospirosis cases in two provinces of Zhejiang and Guangdong. No leptospirosis cases were reported in Henan Province from 2010 to 2020; however, there were 5 cases and 2 cases reported in 2021 and 2022, respectively. There was only one leptospirosis case reported in Shaanxi Province from 2010 to 2017; however, leptospirosis cases were reported in the province for 5 consecutive years since 2018. Leptospirosis cases were reported throughout the year in China from 2010 to 2022, with the peak of incidence found during the period between August and October, and the peak of leptospirosis incidence varied in provinces. A higher number of leptospirosis cases was seen among men than among women, with a male to female ratio of 2.3:1, and the median age of leptospirosis cases was 50 years (interquartile range, 23 years), with the highest proportion of leptospirosis cases reported at ages of 51 to 60 years (23.21%). Among all reported leptospirosis cases, 53.28% were confirmed cases, and the proportion of confirmed cases increased from 35.05% in 2010 to 61.66% in 2022. In addition, there were 67.22% of leptospirosis cases (2 937 cases) reported by comprehensive hospitals, 20.44% (893 cases) by disease control and prevention institutions, 7.23% (316 cases) by grassroots healthcare institutions and 5.10% (223 cases) by other healthcare and medical institutions, and the mortality of reported leptospirosis cases was 1.07% in China from 2010 to 2022, with a higher mortality seen among men than among women (1.39% vs. 0.36%; χ² = 9.52, P = 0.002).

Conclusions: The incidence of

Objective: To investigate the activity of Acorus tatarinowii extracts against dust mites, and to isolate and characterize active ingredient of A. tatarinowii extracts.

Methods: The essential oil components were extracted from A. tatarinowii rhizome powder by rotary evaporation with methanol as solvents, followed by petroleum ether extraction and rotary evaporation. The essential oil was mixed with Tween-80 at a ratio of 1:1 and diluted into concentrations of 1.000 00%, 0.500 00%, 0.250 00%, 0.125 00%, 0.062 50% and 0.031 25%, while diluted Tween-80 served as controls. A. tatarinowii essential oil at each concentration (200 μL) was transferred evenly to filter papers containing 100 adult mites, with each test repeated in triplicate, and controls were assigned for each concentration. Following treatment at 25 °C and 75% relative humidity for 24 h, the mean corrected mortality of mites was calculated. The essential oil components were separated by silica gel column chromatography, and the essential oil was prepared in the positive column of medium pressure; and then, each component was collected. Silica gel column chromatography was run with the mobile phase that consisted of petroleum ether solution containing 10% ethyl acetate and pure ethyl acetate, detection wavelength of 254 nm, positive silica gel column as the chromatography column, and room temperature as the column temperature. Each component of the purified A. tatarinowii essential oil was diluted into 1.000 00% for acaricidal tests. The components with less than 100% acaricidal activity were discarded, and the remaining components were diluted into 50% of the previous-round tests for subsequent acaricidal tests. The components with acaricidal activity were subjected to high-performance liquid chromatography, liquid chromatography-mass spectrometry and pulsed-Fourier transform nuclear magnetic resonance spectroscopy. The structure of active monomer compounds was determined by standard spectral library retrieval and literature review.

Results: A. tatarinowii essential oil at concentrations of 1.000 00%, 0.500 00%, 0.250 00% and 0.125 00% killed all dust mites, and the corrected mortality was all 100%. Exposure to A. tatarinowii extracts at an effective concentration of 0.062 50% for 24 hours resulted in 94.33% mortality of dust mites. Six components (A to F) were separated using gel column chromatography, and components D and E both showed a 100% acaricidal activity against dust mites at a concentration of 0.50000%. In addition, Component D was identified as isoeugenol methyl ether, and Component E as β-asarinol.

Conclusions: The extract of A. tatarinowii essential oil has acaricidal activity, and the isoeugenol methyl ether shows a remarkable acaricidal activity against dust mites.

Objective: To evaluate the potential risk of transmission of angiostrongyliasis by common freshwater snails in Dali Bai Autonomous Prefecture, Yunnan Province, so as to provide insights into local surveillance of angiostrongyliasis.

Methods: Common freshwater snails were collected from Dali Bai Autonomous Prefecture, Yunnan Province from March to April, 2020, and identified and bred in laboratory. SD rats were infected with third-stage larvae of Angiostrongylus cantonensis that were isolated from commercially available Pomacea canaliculata snails in Dali Bai Autonomous Prefecture, and freshwater snails were infected with the first-stage larvae of A. cantonensis that were isolated from the feces of SD rats 39 days post-infection at room temperature. The developmental process and morphological characteristics of worms in hosts were observed, and the percentages of A. cantonensis infections in different species of freshwater snails were calculated. Then, SD rats were infected with the third-stage larvae of A. cantonensis that were isolated from A. cantonensis-infected freshwater snails, and the larval development and reproduction was observed.

Results: More than 3 000 freshwater snail samples were collected from farmlands, ditches and wetlands around Erhai Lake in Dali Bai Autonomous Prefecture, and Cipangopaludina chinensis, P. canaliculata, Parafossarulus striatulus, Oncomelania hupensis robertsoni, Galba pervia, Physa acuta, Radix swinhoei, Assiminea spp., Tricula spp. and Bellamya spp. were morphologically identified. A total of 105 commercially available P. canaliculata snails were tested for A. cantonensis infections, and 2 P. canaliculata snails were found to be infected with A. cantonensis, in which the third-stage larvae of A. cantonensis were isolated. Ten species of freshwater snails were artificially infected with the third-stage larvae of A. cantonensis, and all 10 species of freshwater snails were found to be infected with A. cantonensis, with the highest positive rate of A. cantonensis infections in Bellamya spp. (62.3%, 137/204), and the lowest in C. chinensis (35.5%, 11/31). After SD rats were infected with the third-stage larvae of A. cantonensis isolated from different species of freshwater snails, mature adult worms of A. cantonensis were yielded.

Conclusions: Multiple species of freshwater snails may serve as intermediate hosts of A. cantonensis under laboratory conditions in Dali Bai Autonomous Prefecture of Yunnan Province. Further investigations on natural infection of A. cantonensis in wild snails in Dali Bai Autonomous Prefecture seem justified.

Objective: To investigate the bacterial community diversity in human Demodex mites, so as to provide insights into unraveling the role of human Demodex mites in them caused infectious diseases.

Methods: From June to July 2023, Demodex mites were collected from the faces of college students in a university in Wuhu City using the adhesive tape method, and the V4 region of 16S ribosomal RNA (16S rRNA) gene and the internal transcribed spacer (ITS) gene of nuclear ribosomal DNA were amplified on an Illumina PE250 high-throughput sequencing platform. Sequencing data were spliced according to the overlapping relations and filtered to yield effective sequences, and operational taxonomic units (OTUs) was clustered. The diversity index of obtained OUTs was analyzed, and the structure of the bacterial community was analyzed at various taxonomic levels.

Results: A total of 57 483 valid sequences were obtained using 16S rRNA gene sequencing, and 159 OUTs were classified according to similarity. Then, OUTs at a 97% similarity were included for taxonomic analyses, and the bacteria in Demodex mites belonged to 14 phyla, 20 classes, 51 orders, 72 families, and 94 genera. Proteobacteria was the dominant phylum, and Vibrio, Bradyrhizobium and Variovorax were dominant genera. A total of 56 362 valid sequences were obtained using ITS gene sequencing, and 147 OTUs were obtained, which belonged to 5 phyla, 17 classes, 34 orders, 68 families, and 93 genera and were annotated to Ascomycota, Basidiomycota and Chytridiomycota, with Ascomycota as the dominant phylum, and Alternaria alternata, Epicoccum, Penicillium, and Sarocladium as dominant genera.

Conclusions: There is a high diversity in the composition of bacterial communities in human Demodex mites, with multiple types of microorganisms and high species abundance.

Malaria is one of the most serious mosquito-borne infectious diseases in the world. The global malaria control progress has stalled in recent years, which is largely due to the biological threats from the malaria pathogen Plasmodium and the vector Anopheles mosquitoes. This article provides an overview of biological threats to global malaria elimination, including antimalarial drug resistance, deletions in the malaria rapid diagnostic test target P. falciparum histidine-rich protein 2/3 (Pfhrp2/3) genes, vector insecticide resistance and emergence of invasive vector species, so as to provide insights into malaria and vector research and the formulation and adjustment of the malaria control and elimination strategy.

Objective: To perform a bibliometric analysis of researches on the Plasmodium falciparum repetitive interspersed families of polypeptides (RIFIN) protein from 1993 to 2022 and identify the hot topics in the RIFIN protein research, so as to provide insights into future researches on RIFIN protein.

Methods: RIFIN protein-associated publications were retrieved in the Web of Science Core Collection from 1993 to 2022 and all bibliometric analyses were performed using the software CiteSpace 6.2.4.0. The annual number of RIFIN protein-associated publications was analyzed from 1993 to 2022, and country, author and institution collaboration networks were created. Keywords were extracted from RIFIN protein-associated publications for plotting keyword co-occurrence, clustering, burst and timeline maps to identify the hot topics in the RIFIN protein research.

Results: A total of 745 English RIFIN protein-associated publications were included in the final bibliometric analysis, and there were 18 to 36 publications each year from 1993 to 2022. The top three countries with the highest activity in the RIFIN protein research included the United States, the United Kingdom and France, universities and research institutes were highly active in the RIFIN protein research; however, no authors were identified with a high activity in the RIFIN protein research. There were three keyword clusters in the RIFIN protein-associated publications, including repetitive DNA sequence, molecular epidemiology and antigenic variation. Keyword co-occurrence, burst and timeline analyses showed that previous RIFIN protein-associated publications mainly focused on gene properties and functions, involving keywords of repetitive DNA sequence and evolution, and recent hot topics for the RIFIN protein research shifted to genetic diversity and immune response, involving keywords of genetic diversity, antigenic variation and binding.

Conclusions: The annual number of RIFIN protein-associated publications was relatively stable from 1993 to 2022. This bibliometric analysis may provide insights into future researches on the RIFIN protein.

Driven by international exchanges and climate changes, the invasion and spread of vector Anopheles mosquitoes posed a new challenge to achieving global malaria elimination. Taking the invasion of An. stephensi to exacerbate the malaria epidemic in Africa as an example, this article summarizes the current situation of global Anopheles invasion, and estimates the potential risk of vector Anopheles mosquitoes to unravel the difficulties and challenges in the global malaria elimination program, so as to provide insights into improved early earning and precision control of vector Anopheles mosquito invasion across the world.