To understand the progress of, summarize the lessons learned from and analyze the challenges in the national schistosomiasis elimination program of China in 2024, this article presented the endemic situation of schistosomiasis and national schistosomiasis surveillance results in the People’s Republic of China in 2024. By the end of 2024, Shanghai Municipality, Zhejiang Province, Fujian Province, Guangdong Province and Guangxi Zhuang Autonomous Region continued to consolidate schistosomiasis elimination achievements, and 7 provinces of Jiangsu, Sichuan, Yunnan, Hubei, Hunan, Anhui and Jiangxi maintained the criteria of schistosomiasis transmission interruption. A total of 450 counties (cites, districts) were found to be endemic for schistosomiasis in China in 2024, including 26 061 endemic villages covering 73 630 500 residents at risk of infections. Among the 450 counties (cities, districts) endemic for schistosomiasis, 388 (86.22%) achieved the criteria of schistosomiasis elimination and 62 (13.78%) achieved the criteria of transmission interruption. In 2024, a total of 4 102 624 individuals received immunological tests for schistosomiasis in China, with 44 823 sero-positives identified (1.09% seroprevalence), and a total of 169 722 individuals received parasitological examinations, with 1 egg-positives detected. A total of 27 321 cases with advanced schistosomiasis were documented in China by the end of 2024. In 2024, a total of 575 686 bovines were raised in schistosomiasis-endemic villages of China, and 113 842 bovines received immunological tests, with 235 sero-positives detected (0.21% seroprevalence), while no egg-positives were identified among the 167 475 bovines receiving parasitological examinations. In 2024, snail survey was performed covering an area of 680 498.27 hm² in China, and 190 778.66 hm² snail habitats were identified, including 59.09 hm² emerging snail habitats and 704.23 hm² reemerging snail habitats. In 2024, a total of 19 665 schistosomiasis patients receiving chemotherapy with praziquantel in China, and expanded chemotherapy was given to humans at 571 722 person-times and to bovines at 306 740 herd-times. In addition, snail control with chemical treatment covered 117 111.37 hm² snail habitats across China in 2024, and the actual area of chemical treatment was 66 562.95 hm², while environmental improvements were performed in snail habitats covering an area of 1 374.26 hm². The national schistosomiasis surveillance results showed that the mean prevalence rates of Schistosoma japonicum infections were both 0 among humans and bovines in China in 2024, and no S. japonicum infection was detected in snails. These data demonstrated that the prevalence of schistosomiasis remained at a low level in China in 2024; however, the areas of snail habitats remained high and the number of fenced cattle showed a slight increase. To address these risks, it is imperative to maintain the integrated strategy with an emphasis on management of the source of S. japonicum infection and intensified snail control in high-risk areas, and to reinforce schistosomiasis surveillance and forecast and snail control in high-risk areas.

The goal of achieving elimination of schistosomiasis across all endemic counties in China by 2030 was proposed in the Outline of the Healthy China 2030 Plan. On June 16, 2023, the Action Plan to Accelerate the Elimination of Schistosomiasis in China (2023—2030) was jointly issued by National Disease Control and Prevention Administration and other 10 ministries, which deployed the targets and key tasks of the national schistosomiasis elimination programme in China. This article describes the progress of the national schistosomiasis control programme, analyzes the opportunities to eliminate schistosomiasis, and proposes targeted recommendations to tackle the challenges of schistosomiasis elimination, so as to accelerate the process towards schistosomiasis elimination and facilitate the building of a healthy China.

On June 16, 2023, National Disease Control and Prevention Administration of the People’s Republic of China, in collaboration with other ministries, formulated and issued the Action Plan to Accelerate the Elimination of Schistosomiasis in China (2023—2030). The implementation of this plan provides an important basis for achieving the targets set in the “Healthy China 2030” action plan and the implementation of the rural revitalization strategy. This paper describes the background, principles, targets, control strategies, safeguard measures and effectiveness evaluation of the plan, in order to guide the scientific and standardized implementation of actions for schistosomiasis elimination at the grassroots level, and facilitate the progress towards elimination of schistosomiasis in China with a high quality.

Objective To understand the current status of capacity building in schistosomiasis control institutes in schistosomiasis-endemic provinces (municipality, autonomous region) of China. Methods The responsibilities and construction requirements of various schistosomiasis control institutions were surveyed by expert discussions, and field interviews and visits during the period between May and June, 2023, and the questionnaire for capacity maintenance and consolidation in schistosomiasis control institutions was designed. An online questionnaire survey was conducted in county-, municipal-, and provincial-level institutions that undertook schistosomiasis control and surveillance activities through the Wenjuanxing program. The distribution of schistosomiasis control institutions, the status of institutions, departments and staff undertaking schistosomiasis control activities and the translation of scientific researches on schistosomiasis control in China were analyzed. The laboratories accredited by China National Accreditation Service for Conformity Assessment (CNAS) were considered to be capable for testing associated with schistosomiasis control, and the testing capability of schistosomiasis control institutions was analyzed. Results A total of 486 valid questionnaires were recovered from 486 schistosomiasis control institutions in 12 endemic provinces (municipality, autonomous region) of China, including 12 provincial-level institutions (2.5%), 77 municipal-level institutions (15.8%) and 397 county-level institutions (81.7%). Of all schistosomiasis control institutions, 376 (77.4%) were centers for disease control and prevention or public health centers, 102 (21.0%) were institutions for schistosomiasis, endemic disease and parasitic disease control, and 8 (1.6%) were hospitals, healthcare centers or others. There were 37 713 active employees in the 486 schistosomiasis control institutions, including 5 675 employees related to schistosomiasis control, and the proportions of employees associated with schistosomiasis control among all active employees were 5.9% (231/3 897), 5.5% (566/10 134), and 20.6% (4 878/23 682) in provincial-, municipal-, and county-level institutions, respectively. There were 3 826 full-time employees working in schistosomiasis control activities, with 30.5% (1 166/3 826), 34.6% (1 324) and 34.9% (1 336/3 826) at ages of 40 years and below, 41 to 50 years and over 50 years, and there were 1 571 (41.0%) full-time schistosomiasis control employees with duration of schistosomiasis control activities for over 25 years, and 1 358 (35.5%) employees with junior professional titles and 1 290 with intermediate professional titles (35.5%), while 712 (18.6%) full-time employees working in schistosomiasis control activities had no professional titles. The three core schistosomiasis control activities included snail control (26.3%, 374/1 420), epidemics surveillance and management (25.4%, 361/1 420) and health education (18.8%, 267/1 420) in schistosomiasis control institutions. The Kato-Katz method, miracidium hatching test with nylon gauzes, and indirect haemagglutination assay (IHA) were the most commonly used techniques for detection of schistosomiasis, and there were less than 50% laboratories that had capabilities or experimental conditions for performing enzyme-linked immunosorbent assay (ELISA), dipstick dye immunoassay (DDIA), dot immunogold filtration assay (DIG-FA), loop-mediated isothermal amplification (LAMP) and polymerase chain reaction (PCR) assays. During the period from 2018 to 2022, schistosomiasis control institutions had undertaken a total of 211 research projects for schistosomiasis control, with a total funding of 18.596 million RMB, published 619 articles, participated in formulation of 13 schistosomiasis control-related criteria, and applied for 113 schistosomiasis control-related patents, including 101 that were granted, and commercialized 4 scientific research outcomes. Conclusions The proportion of independent specialized schistosomiasis control institutions is low in schistosomiasis control institutions in China, which suffers from problems of unsatisfactory laboratory testing capabilities, aging of staff and a high proportion of low-level professional titles. More investment into and intensified schistosomiasis control activities and improved capability building and talent cultivation in schistosomiasis control institutions are recommended to provide a powerful support for high-quality elimination of schistosomiasis in China.

Objective To evaluate the molluscicidal effect and cost of spraying molluscicides with drones against Oncomelania hupensis snails in marshland and lake areas, so as to provide new insights into field snail control in China. Methods A marshland and lake setting measuring approximately 12 000 m² was selected in Wanzhi District, Wuhu City on June 2023 as the test field, and assigned to four groups, of 3 000 m² in each group. Environmental cleaning was not conducted in groups A or B, which were given 5% niclosamide ethanolamine salt granules sprayed with knapsack-type sprayers and drones at a dose of 40 g/m², and environmental cleaning was conducted in groups C and D, which were given 5% niclosamide ethanolamine salt granules sprayed with drones and knapsack-type sprayers at a dose of 40 g/m², respectively. O. hupensis snails were surveyed before chemical treatment and 1, 3, 5, 7, 14 days post-treatment. The uniformity of chemicals was determined on the day of treatment, and the snail mortality, corrected snail mortality and density of living snails were calculated and compared among groups. The cost of molluscicides, labor fees of environmental cleaning and chemical treatment and cost of equipment were calculated, and the cost for a 1% reduction in the mean density of living snails was calculated 14 days post-treatment. Results The mean densities of living snails and mortality rates of snails were 1.82 to 2.85 snails/0.1 m² and 1.41% to 2.94% in groups A, B, C and D before chemical treatment, and the mortality and corrected mortality of snails were 55.75%, 49.32%, 85.94% and 87.50%, and 55.00%, 48.47%, 85.70% and 87.29% in groups A, B, C and D 14 days post-treatment. There was a significant difference in the mortality of snails among the four groups 14 days post-treatment (χ² = 38.735, P < 0.005), and there was a higher snail mortality in Group D than in Group A (χ² = 16.876, P < 0.005), and higher in Group C than in Group B (χ² = 20.508, P < 0.005). The density of living snails reduced by 55.00%, 43.94%, 90.43% and 87.14% 14 days post-treatment relative to pre-treatment in groups A, B, C and D, respectively. The test for uniformity of chemicals showed that the mean dose of molluscicides were 57.34, 55.21, 40.19 g/m² and 32.37 g/m² in groups A, B, C and D, respectively, and the minimal standard deviation (7.07) and coefficient of variation (0.18) of mean doses were seen in Group C. The costs for chemical treatment were 0.33 Yuan in groups A and B and 1.53 Yuan in groups C and D, respectively. The costs for a 1% reduction in the mean density of living snails were 17.82, 22.47, 50.73 Yuan and 52.56 Yuan in groups A, B, C, and D 14 days post-treatment, respectively. Conclusions The molluscicidal effect and cost of spraying 5% niclosamide ethanolamine salt granules with drones are comparable to manual spraying, and chemical treatment with drones are high in uniformity of molluscicides, time- and labor-saving, and feasible for applications in complex environments, which deserves widespread applications in the field of snail control.

Objective To evaluate the molluscicidal effect of spraying different formulations of niclosamide ethanolamine salt with drones against Oncomelania hupensis in ditches. Methods A semi-dry and semi-wet ditch with O. hupensis snails was selected in the second branch field of Jiangbei Farm, Jiangling County, Hubei Province in May 2023, and divided into 4 experimental areas, named groups A1, A2, B1 and B2. Environmental cleaning was performed in groups A1 and B2, and was not conducted in groups A2 or B2. Then, 50% wettable powder of niclosamide ethanolamine salt was sprayed with drones at an effective dose of 2 g/m² in groups A1 and A2, and 5% niclosamide ethanolamine salt granule was sprayed with drones at an effective dose of 2 g/m² in groups B1 and B2. O. hupensis snails were surveyed using the systematic sampling method 1, 3, 5, 7, 14 days after spraying, and the natural mortality and corrected mortality of O. hupensis snails were calculated. Results The occurrence of frames with living snails, mean density of living snails and natural mortality of snails were 97.50% (117/120), 6.30 snails/0.1 m² and 1.18% (9/765) in the test ditch before spraying, respectively. There were significant differences in the mortality of snails among four groups 1, 3, 5, 7 and 14 days after spraying niclosamide formulations with drones (χ² = 17.230, 51.707, 65.184, 204.050 and 34.435, all P values < 0.01). The overall mortality rates of snails were 94.51% (1 051/1 112), 79.44% (908/1 143), 96.54% (977/1 012) and 88.55% (1 021/1 153) in groups A1, A2, B1 and B2 (χ² = 207.773, P < 0.05), respectively. In addition, there was no significant difference in the overall snail mortality between groups A1 and B1 (P > 0.05), and the snail mortality in groups A1 and B1 were both statistically different from that in groups A2 and B2 (all P values < 0.05). Conclusion Both 50% wettlable powder of niclosamide ethanolamine salt and 5% niclosamide ethanolamine salt granule sprayed with drones are active against O. hupensis snails in ditches, and environmental cleaning may improve the molluscicidal effect.

Objective To evaluate the molluscicidal effect of spraying 5% niclosamide ethanolamine salt granules with drones against of Oncomelania hupensis snails in snail habitats in marshland areas. Methods From September to October, 2022, marshlands were sampled from Dantu District, Zhenjiang City, Jiangsu Province as study areas, and assigned into four groups, of approximately 3 000 m² per group. In Group A, environmental cleaning was performed, followed by spraying 5% niclosamide ethanolamine salt granules with knapsack sprayers at a dose of 40 g/m², and in Group B, 5% niclosamide ethanolamine salt granules were sprayed with knapsack sprayers at a dose of 40 g/m² without environmental cleaning, while in Group C, environmental cleaning was conducted, followed by spraying 5% niclosamide ethanolamine salt granules with drones at a dose of 40 g/m², and in Group D, 5% niclosamide ethanolamine salt granules were sprayed with drones at a dose of 40 g/m² without environmental cleaning. Then, the study areas in each group were equally divided into six blocks, with Block 1 for baseline surveys and blocks 2 to 6 for snail surveys 1, 3, 5, 7, 14 days following chemical treatment. The mortality of snails and the reduction of the density of living snails were calculated. Results A total of 132 frames were surveyed during the period from September to October 2022, and the occurrence of frames with living snails and means density of living snails were 61.36% (81/132) and 1.58 snails/0.1 m², respectively. The overall mortality rates of snails were 43.02% (77/179), 38.69% (77/199), 47.78% (86/180) and 31.02% (58/187) 14 days following chemical treatment in groups A, B, C and D, respectively (χ² = 11.646, P < 0.05), and there were differences detected in the snail mortality between group A and D, and between groups C and D (both P_adjusted values < 0.05). The adjusted mortality rates of snails were 37.42%, 36.07%, 38.85% and 40.40% in groups A, B, C and D 14 days post-treatment, and the density of living snails decreased by 48.10%, 63.29%, 67.09% and 69.62% 14 days post-treatment relative to pre-treatment, respectively. Conclusions Chemical treatment with drones is feasible for O. hupensis snail control in marshland areas; however, the molluscicidal effect of spraying 5% niclosamide ethanolamine salt granules with drones is comparable to spraying chemicals manually in marshland areas regardless of environmental cleaning.

Objective To investigate the health education needs and available resources in schistosomiasis-endemic areas based on integration of community resources, and to explore the operation pathways for health education and promotion during the stage of schistosomiasis elimination. Methods A community was selected from Nanji Township, Xinjian District, Nanchang City, Jiangxi Province around the Poyang Lake areas as the study site, and a questionnaire survey on health education needs for schistosomiasis control was conducted among permanent residents at ages of 20 years in the community during the period between June and July, 2022 using face-to-face interviews. In addition, the resources available for the community-based schistosomiasis control health education were investigated among workers in township-level specialized institutions, members of civil society organizations, villagers, teachers and high and primary school students through field observations, field surveys and thematic interviews. Results A total of 304 individuals participated in the questionnaire survey on community-based health education needs for schistosomiasis control, and 94.41% (287/304) and 93.42% (284/304) of the respondents were most interested in knowing/understanding knowledge of the morphology of schistosomes and knowledge associated with the transmission route of schistosomiasis. The four most popular patterns for disseminating schistosomiasis control knowledge included live broadcasting of schistosomiasis control videos (94.41%, 287/304), printed brochures (89.80%, 273/304), special lectures by doctors (62.50%, 190/304) and physical health education materials for schistosomiasis control (61.51%, 187/304). There were 96.71% (294/304) and 77.63% (236/304) of respondents that accepted the participation of township healthcare center and township government/village committees in dissemination of schistosomiasis control knowledge, and there were 95.72% (291/304) and 80.59% (245/304) of respondents that mainly acquired schistosomiasis control knowledge through village allocation of leaflets and volunteer schistosomiasis control activities, respectively. There was 96.71% (294/304) of respondents participating in the dissemination activities of schistosomiasis control knowledge held by village committees, township healthcare centers, and high and primary schools/kinder-gartens, and 61.25% (177/289) of respondents were willing to participate in volunteer schistosomiasis control activities. A total of 115 individuals participated in the survey of available resources for community-based schistosomiasis control health education, and there were a large number of organizational, human and cultural resources in the community that were useful for health communication services. Conclusions The abundant human and material resources from rural communities in schistosomiasis-endemic areas may be integrated into schistosomiasis control health education to generate a rural health education pathway with the joint participation of schistosomiasis control institutions, township governments, community departments and community residents, which may provide insights into the future development of schistosomiasis control health education.

Objective To screen differentially expressed long non-coding RNAs (lncRNAs) in the liver of mice infected with Schistosoma japonicum during the chronic pathogenic stage and identify their functions, so as to provide insights into unravelling the role of lncRNAs in S. japonicum infection-induced liver disorders. Methods Twenty 6-week-old C57BL/6 mice were randomly divided into two groups, of 10 animals each group. Each mouse in the experimental group was infected with (15 ± 2) S. japonicum cercariae via the abdomen for modeling chronic S. japonicum infection in mice, and distilled water served as controls. All mice were sacrificed 70 days post-infection, and mouse liver specimens were sampled for RNA extraction and library construction. All libraries were sequenced on the Illumina NovaSeq 6000 sequencing platform. Data cleaning was performed using the fastp software, and reference genome alignment and gene expression (FPKM) calculation were performed using the HISAT2 software. Potential lncRNA sequences were predicted using the software CNIC, CPC, Pfam, and PLEK, and potential lncRNAs were screened. Differentially expressed lncRNAs were screened with the DESeq2 software and subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses to identify biological processes and metabolic pathways involved in target genes of differentially expressed lncRNAs. Results A total of 333 potential lncRNAs were screened, and 67 were identified as differentially expressed lncRNAs, including 49 up-regulated and 18 down-regulated lncRNAs. A total of 53 target genes were predicted for differentially expressed lncRNAs. GO enrichment analysis showed that these target genes were mainly enriched in biological process and molecular function, among which Sema7a, Arrb1, and Ccl21b genes may be hub target genes for positive regulation of extracellular regulated protein kinase 1 (ERK1) and ERK2 cascades and may participate in the regulation of collagen expression. KEGG enrichment analysis showed that the target genes of differentially expressed lncRNAs were mainly enriched in cytokine-cytokine receptor interaction, viral protein interactions with cytokines and cytokine receptors, chemokine signaling pathway, and nuclear factor kappa-B (NF-κB) signaling pathway. Conclusions This study identifies differentially expressed lncRNAs and functional enrichment of their target genes in the liver of mice during the chronic pathogenic stage of S. japonicum infection. Up-regulated lncRNAs may affect biological processes of ERK1/2 cascades and chemokine signaling pathways via target genes Sema7a, Arrb1, and Ccl21b, thereby affecting collagen expression and inflammatory signal pathways, ultimately affecting the development of liver disorders.

To understand the progress of national schistosomiasis elimination program of China in 2023 and summarize the lessons and experiences, data on the endemic status of schistosomiasis and national schistosomiasis surveillance results in the People’s Republic of China were collected and analyzed at a national level. By the end of 2023, Shanghai Municipality, Zhejiang Province, Fujian Province, Guangdong Province and Guangxi Zhuang Autonomous Region continued to consolidate the achievements of schistosomiasis elimination, and Sichuan and Jiangsu provinces maintained the criteria of transmission interruption, while Yunnan and Hubei provinces were identified to achieve the criteria of transmission interruption in 2020, and Anhui, Jiangxi and Hunan provinces achieved the criteria of transmission interruption in 2023. A total of 451 counties (cites, districts) were found to be endemic for schistosomiasis in China in 2023, including 26 250 endemic villages covering 73 034 500 residents at risk of infections. Among the 451 endemic counties (cities, districts), 78.49% (354/451) achieved the criteria of schistosomiasis elimination and 21.51% (97/451) achieved the criteria of transmission interruption, respectively. In 2023, a total of 4 216 643 individuals received immunological tests, with 47 794 sero-positives identified, and a total of 184 216 individuals received parasitological examinations, with 4 egg-positives detected. A total of 27 768 cases with advanced schistosomiasis were documented in China by the end of 2023. In 2023, 539 548 bovines were raised in schistosomiasis-endemic areas of China, and 125 440 bovines received immunological tests, with 124 sero-positives detected, while no egg-positives were identified among the 133 508 bovines receiving parasitological examinations. In 2023, snail survey was performed at an area of 641 339.53 hm² and 184 819.77 hm² snail habitats were identified, including 51.53 hm² emerging snail habitats and 642.25 hm² reemerging snail habitats. In 2023, there were 20 198 schistosomiasis patients receiving praziquantel chemotherapy, and 598 183 person-time individuals and 283 954 herdtime bovines were given expanded chemotherapy. In 2023, snail control with chemical treatment was performed in 116 347.95 hm² snail habitats, and the actual area of chemical treatment was 65 690.89 hm², while environmental improvements were performed in snail habitats covering an area of 1 334.62 hm². The national schistosomiasis surveillance results showed that the mean prevalence of Schistosoma japonicum infections were both zero among humans and bovines in 2023, and no S. japonicum infection was detected in snails. These data demonstrated that transmission interruption of schistosomiasis had been achieved across all endemic provinces in China in 2023, and the endemic status of schistosomiasis tended to be stable, while advanced cases were predominant among all schistosomiasis cases. However, the areas of snail habitats remained high and cattle re-raising was very common in some regions. Intensified schistosomiasis surveillance and forecast and snail control in high-risk areas are needed.