Efficacy of artemether and artesunate in mice infected with praziquantel non-susceptible isolate of Schistosoma japonicum.

Praziquantel is currently the only drug of choice for the treatment of human Schistosoma japonicum infections, and praziquantel-based chemotherapy has been proved to be generally effective to control the morbidity and reduce the prevalence and intensity of S. japonicum infections. However, the potential emergence of praziquantel resistance in S. japonicum seriously threatens the elimination of this neglected tropical disease in China. The purpose of this study was designed, in mouse animals, to evaluate the in vivo efficacy of artemether and artesunate against praziquantel non-susceptible S. japonicum. Mice infected with a praziquantel non-susceptible isolate and a praziquantel-susceptible isolate of S. japonicum were treated with artemether and artesunate at a single oral dose of 300 mg/kg given once on each of days 7-8 and 35-36 post-infection to assess the efficacy against juvenile and adult worms. Administration with artemether and artesunate at a single oral dose of 300 mg/kg on each of days 7-8 post-infection resulted in total worm burden reductions of 72.8 and 73.5% in mice infected with praziquantel-susceptible S. japonicum, and 77.9 and 74.1% in mice infected with the non-susceptible isolate (both P values >0.05), while the same treatments given on days 35-36 post-infection reduced total worm burdens by 71.4 and 69.6% in mice infected with the susceptible isolate, and 75.3 and 69.6% in mice infected with the non-susceptible parasite (both P values >0.05). It is concluded that there is no evidence for reduced susceptibility of artemether and artesunate in praziquantel non-susceptible S. japonicum.

In vivo activity of dihydroartemisinin against Schistosoma mansoni schistosomula in mice.

Dihydroartemisinin, an anti-malarial agent, has been shown to exhibit activity against Schistosoma japonicum and S. mansoni. The purpose of the present study was to investigate the in vivo activity of dihydroartemisinin against juvenile S. mansoni and the changes to the genital system among worms surviving drug treatment. Mice were infected with 200 S. mansoni cercariae each and randomly assigned to groups. Dihydroartemisinin at a single oral dose of 300 mg/kg was given to mice on Days 14 or 16, 18, 20, 21, 22, 24, 26 or 28 post-infection, to assess the efficacy of dihydroartemisinin against juvenile S. mansoni. Mice were treated with dihydroartemisinin using various protocols with the total drug dose of 900 mg/kg, to investigate the efficacy of dihydroartemisinin against the schistosomula of S. mansoni. In addition, changes to the genital system among worms surviving dihydroartemisinin treatment, were recorded. An oral dose of dihydroartemisinin of 300 mg/kg was given to mice on Days 14, 16, 18, 20, 21, 22, 24, 26 or 28 days post-infection; this resulted in a 65.0-82.4% reduction in total worm burden and a 70.9-83.0% female worm burden. Better results were seen when treatment was given 20-24 days post-infection. Administration of multiple-dose and low-oral-dose dihydroarteminisinin (at doses of 90, 180, 300 and 450 mg/kg) at different times, reduced total worm burdens by 88.7-99.1% and female worm burdens by 93.2-99.5%. The egg tubercles in mice livers were significantly reduced following treatment; in some mice no egg tubercles were found. These findings indicate dihydroartemisinin exhibits high in vivo activity against the schistosomula of S. mansoni. It causes damage to the genital system of worms, influences the development of of S. mansoni worms, reduces the oviposition of surviving worms and enhances the formation of granulomas around tissue-trapped eggs, thereby reducing damage to the infected mammalian host.

[Bibliometric analysis of literature regarding integrated schistosomiasis control strategy with emphasis on infectious source control].

OBJECTIVE: To evaluate the outcomes of implementation of integrated schistosomiasis control strategy with emphasis on infectious source control using a bibliometric method. METHODS: The literature pertaining to integrated schistosomiasis control strategy with emphasis on infectious source control was retrieved from CNKI, Wanfangdata, VIP, PubMed, Web of Science, BIOSIS and Google Scholar, and a bibliometric analysis of literature captured was performed. RESULTS: During the period from January 1, 2004 through September 30, 2014, a total of 94 publications regarding integrated schistosomiasis control strategy with emphasis on infectious source control were captured, including 78 Chinese articles (82.98%) and 16 English papers (17.02%). The Chinese literature was published in 21 national journals, and Chinese Journal of Schistosomiasis Control had the largest number of publications, consisting of 37.23% of total publications; 16 English papers were published in 12 international journals, and PLoS Neglected Tropical Diseases had the largest number of publications (3 publications). There were 37 affiliations publishing these 94 articles, and National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (16 publications), Anhui Institute of Schistosomiasis Control (12 publications) and Hunan Institute of Schistosomiasis Control (9 publications) ranked top three affiliations in number of publications. A total of 157 persons were co-authored in these 94 publications, and Wang, Zhou and Zhang ranked top 3 authors in number of publications. CONCLUSION: The integrated schistosomiasis control strategy with emphasis on infectious source control has been widely implemented in China, and the achievements obtained from the implementation of this strategy should be summarized and transmitted internationally.