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The golden apple snail Pomacea canaliculatais an invasive pest that causes extensive damage to agricultural production. P. canaliculatais also an intermediate host of Angiostrongylus cantonensis, which causes human eosinophilic meningitis. In this study, the molluscicidal activity and safety profile of a novel molluscicide PBQ [1-(4-chlorophenyl)-3-(pyridin-3-yl)urea] were evaluated. PBQ exhibited strong molluscicidal potency against adult and juvenile snails (LC50values of 0.39 and 0.07 mg/L, respectively). In field trials, PBQ killed 99.42% of the snails at 0.25 g a.i./m2. An acute toxicity test in rats demonstrated that PBQ is a generally nonhazardous chemical. PBQ is also generally safe for nontarget organisms including Brachydanio rerio, Daphnia magna, and Apis melliferaL. Transcriptomics analysis revealed that PBQ had a significant impact on the carbohydrate and lipid metabolism pathways, which provided insights into its molluscicidal mechanism. These results suggest that PBQ could be developed as an effective and safe molluscicide for P. canaliculatacontrol.

The advent and development of genome editing technology has opened up the possibility of directly targeting and modifying genomic sequences in the field of life sciences with rapid developments occurring in the last decade. As a powerful tool to decipher genome data at the molecular biology level, genome editing technology has made important contributions to elucidating many biological problems. Currently, the three most widely used genome editing technologies include: zinc finger nucleases (ZFN), transcription activator like effector nucleases (TALEN), and clustered regularly interspaced short palindromic repeats (CRISPR). Researchers are still striving to create simpler, more efficient, and accurate techniques, such as engineered base editors and new CRISPR/Cas systems, to improve editing efficiency and reduce off-target rate, as well as a near-PAMless SpCas9 variants to expand the scope of genome editing. As one of the important animal protein sources, fish has significant economic value in aquaculture. In addition, fish is indispensable for research as it serves as the evolutionary link between invertebrates and higher vertebrates. Consequently, genome editing technologies were applied extensively in various fish species for basic functional studies as well as applied research in aquaculture. In this review, we focus on the application of genome editing technologies in fish species detailing growth, gender, and pigmentation traits. In addition, we have focused on the construction of a zebrafish (Danio rerio) disease model and high-throughput screening of functional genes. Finally, we provide some of the future perspectives of this technology.

The burden of schistosomiasis remains a global public health problem, especially in sub-Saharan Africa despite progress in terms of morbidity control. Successful control efforts achieved by China in the last six decades came with considerable experience and lessons that could benefit schistosomiasis control programs in other endemic countries. China's role and commitment to global health cooperation has become increasingly important; this has created a platform for partnership with developing partners for the establishment of Forum on China–Africa health cooperation which prioritizes the pursuit of global elimination target for schistosomiasis and malaria, control of HIV/AIDS, and improved access to reproductive health care. Chinese government's commitment towards achieving schistosomiasis elimination in Africa prompted the establishment of Institution-based Network on China–Africa Cooperation for Schistosomiasis Elimination (INCAS), by the National Institute of Parasitic Diseases to promote schistosomiasis elimination in Africa. Schistosomiasis experts from six provincial institutions and counterparts from 10 African countries participated in the first workshop on China–Africa cooperation for Schistosomiasis Elimination in Africa at Lilongwe, Malawi, in 2015. Experts at the inaugural meeting shared experiences from their national schistosomiasis control programs, as well as identified areas for collaborative synergy targeting schistosomiasis elimination in Africa. The establishment of INCAS, which comprises of 28 member-institutions from China and Africa, was proposed at this meeting. We, therefore, provide information on INCAS activities, cooperation mechanism, as well as assess the strengths, weaknesses, opportunities, and threats as we target schistosomiasis elimination in Africa using the INCAS platform.

Schistosomiasis was one of the most prevalent severe infectious diseases in China. Most of the control plans implemented were based on local settings; thus, the national schistosomiasis control program involved different control phases. These included a working mechanism based on multisectoral cooperation which involved government at all levels, communities, and professionals. It also involved updating the technical strategies and interventions through intensive research, to provide adequate support for programs at different stages with changing natural and social features. To commemorate the 61st anniversary of publishing Chairman Mao Zedong's two poems titled Farewell to the god of plague, we have distilled lessons learnt from national schistosomiasis control programs, which could be transferred to other endemic countries. Based on this work, we published a series of articles to demonstrate the successive programs in different areas or levels in China, and also discussed how best to apply those successive experiences into African countries where schistosomiasis is still a public health problem. There are three major lessons learnt from the Chinese national schistosomiasis control program over the last six decades: (1) sustained commitment by the Chinese governments, from central to local levels; (2) continuous update of control strategies and interventions applied at the village level, based on local settings; and (3) maintaining surveillance-response systems implementation in programs at all levels. With sustained efforts, only 37,000 patients including 2.9% advanced patient cases were found in the country, with six provinces out of the 12 endemic provinces yet to achieve transmission interruption, based on the epidemiological report in 2017. Therefore, Chinese experiences in disease control program are sufficient to promote disease control programs in other developing countries, which would also improve the visibility of Chinese contribution to the world disease control programs. Pursuit of this global engagement will also provide the impetus to maintain our surveillance-response capacity in the post-elimination stage.

ABSTRACTA series of novel salicylanilide ester derivatives were synthesized, characterized, and evaluated for cercaricidal potential against Schistosoma japonicumand molluscicidal potential against Oncomelania hupensis. Four derivatives exhibited remarkable cercaricidal activity superior to that of niclosamide. Among them, the most active compound, 4-chloro-2-((2-methoxy-4-nitrophenyl)carbamoyl)phenyl 4-methoxybenzoate (compound 4c), showed a marked minimum effective cercaricidal concentration as low as 0.43 μM and significant molluscicidal activity, with a 50% lethal concentration (LC50) of 0.206 g/m2. Particularly, compound 4c displayed 88-fold decreased fish toxicity on Danio rerioand 44-fold reduced cytotoxicity on human kidney HEK293 cells in comparison with the toxicity of niclosamide. The results indicated that 4c could serve as a promising drug candidate, with environmental safety properties, against Schistosoma japonicumat transmission stages. The preliminary molecular mechanism of target compounds in Schistosoma japonicumcercariae was also investigated. Salicylanilide ester derivatives exhibited an inhibitory effect on nitric oxide synthase (NOS) but no effect on lactate dehydrogenase (LDH) and acetylcholinesterase (AChE), and a strong and significant correlation between NOS inhibitory efficacy and cercaricidal activity was observed. In addition, 4c could downregulate the expression of NOS in a dose-dependent manner. These results suggested that NOS was probably one of the drug targets of salicylanilide esters.

Climate change has been known to cause variations in the geographically suitable areas for the schistosome-transmitting Oncomelania hupensis (O. hupensis). The spread of snails not only depends on the degree of warming but also on the socioeconomic development of the next few decades. Shared socioeconomic pathways (SSPs) published by CMIP6 consider carbon emission pathways as well as influences of distinct types of social development and land use on the regional climate, providing the possibility to accurately evaluate the impact of socioeconomic development and climate variation on the spread of O. hupensis. This study employed SSP126, SSP245, SSP370, and SSP585 and the correlative approach to explore the impacts of climate change and socioeconomic development on the potential diffusion areas for O. hupensisin China. The results exhibited strong evidence that O. hupensiswill spread in the north of the middle and lower reaches of the Yangtze River and disappear from a small part of its current southern habitat, whereas in Sichuan and Yunnan, O. hupensismay spread slightly to the southeast. The projection also demonstrated that fossil fuel-driven development (SSP585) will be more conducive to the spread of O. hupensisbreeding sites in the 2030s, whereas the continuous increase in snail breeding habitats under the regional rivalry path (SSP370) may lead to great challenges in snail control in the long term (2020–2080).

To effectively promote the implementation of interventions, the identification of high-risk groups and the characteristics of Clonorchis sinensisinfection in endemic regions are needed. In a clonorchiasis-endemic area, local residents were randomly enrolled for helminth egg examination in June 2016. The prevalence in subpopulations as well as the knowledge, attitudes, and behaviours and the factors influencing clonorchiasis in egg-positive populations were analysed. A total of 2282 local residents participated in the survey; the C. sinensisprevalence was 48.6% (1109 persons). A higher prevalence was found in males (62.6%) than in females (29.7%). People older than 30years had the highest prevalence (52.7%–57.6%). Among the 888 persons who were infected with C. sinensisand participated the questionnaire investigation, 19.0% (169/888) knew that it could cause cancer. In addition, 60.6% of people reported that they intended to keep eating raw fish despite knowing the risk of infection. The two primary reasons for continuing to eat raw fish were the disease being regarded as not serious (38.3%) and the belief that anti-parasite medications are effective (39.6%). A total of 94.4% (797/844) of responders reported eating raw fish more frequently in the home than outside of the home. Our study revealed a notably high C. sinensisprevalence in the study area. Awareness of clonorchiasis disease severity should be increased among high-risk individuals and families in highly endemic areas.