Using a mouse model, we previously demonstrated that subcutaneous infection with the JaTH160 strain of Japanese encephalitis virus (JEV) causes significantly higher virulence and stronger virus propagation in the brain compared with that of the JaOArS982 strain. We also showed that the JaTH160 strain, but not JaOArS982, expresses the NS1’ protein and that NS1’ enhances JEV production in avian cells and embryonated chicken eggs. In this study, we examined whether NS1’ expression affects virulence in mice infected with the JaOArS982 and JaTH160 strains using the corresponding recombinant viruses S982-IC and JaTH-IC. Expression of the NS1’ protein in S982-IC diminished the mortality in mice, whereas S982-IC viruses without NS1’ caused 40–60% mortality. However, the viral loads in the brains of these mice were not significantly different despite the dvariation in NS1’ expression. JaTH-IC viruses depleted of the NS1’ protein exhibited high mortality levels, similar to those of the virus expressing NS1’. Previous studies showed that the NS1’ protein plays a role in the enhanced virulence of the JEV SA14 strain in mice. However, our current data suggest that NS1’ protein expression in S982-IC reduces, rather than enhances, the mortality in mice. Thus, the effect of NS1’ on pathogenicity in vivo may vary among virus strains. Our data also suggest that the reduced mortality resulting from NS1’ expression in S982-IC is not simply due to viral replication in the brains. Further investigation is needed to uncover the mechanism by which NS1’ affects pathogenicity in JEV-infected animals.

Background: The intestinal coccidian protozoa Cyclospora cayetanensis has emerged as an important cause of parasitic diarrhea among children living in developing countries. This study aimed to determine the prevalence of Cyclospora among the school children of Kathmandu with reference to various associated risk factors.Methodology: A total of five hundred and seven stool samples from students between the age of 3–14 years, studying in 13 different schools in Kathmandu were collected during the study period (May–November, 2014) and processed at the Public Health Research Laboratory, Institute of Medicine, Kathmandu, Nepal. A modified acid fast staining technique (Kinyoun’s method) was used to detect oocyst of Cyclospora from the formal-ether concentrated stool samples.Results: Cyclospora was detected in 3.94% (20/507) of the stool samples examined. The prevalence was found to be highest among the students in the 3–5 year age group i.e. 10.15% (13/128), peaking during the rainy season (June–August). The detection rate was found to be significantly higher (p < 0.05) among children presenting with diarrheal symptoms, household keeping livestock and consumers of raw vegetables/fruits, showing a prevalence of 10.57% (11/104), 10.11% (9/89) and 7.25% (14/193) respectively.Conclusion: Consumption of untreated drinking water, fresh produce (raw fruits/vegetables) without proper washing and the presence of livestock at home were found to be predisposing factors for higher susceptibility of infection due to Cyclospora. This finding confirms the existence of a public-health issue with potentially serious consequences whereby children can be infected through exposure to oocysts in contaminated food and water and get ill as a result.

Dengue fever (DF), one of the most important emerging arboviral diseases, is transmitted through the bite of container breeding mosquitoes Aedes aegypti and Aedes albopictus. A household entomological survey was conducted in Dhaka from August through October 2000 to inspect water-holding containers in indoor, outdoor, and rooftop locations for Aedes larvae. The objective of this study was to determine mosquito productivity of each container type and to identify some risk factors of households infested with Aedes larvae. Of 9,222 households inspected, 1,306 (14.2%) were positive for Aedes larvae. Of 38,777 wet containers examined, 2,272 (5.8%) were infested with Aedes larvae. Containers used to hold water, such as earthen jars, tanks, and drums were the most common containers for larval breeding. Tires in outdoor and rooftop locations of the households were also important for larval breeding. Although present in abundance, buckets were of less importance. Factors such as independent household, presence of a water storage system in the house, and fully/partly shaded outdoors were found to be significantly associated with household infestation of Aedes larvae. Identification and subsequent elimination of the most productive containers in a given area may potentially reduce mosquito density to below a level at which dengue transmission may be halted.

For many years, Japan has been silent on the achievements of Japan’s Overseas Development Assistance program including the health improvement of foreign countries. Japan’s contribution to global health communities through G8 process including Hashimoto Initiative is steadfast. On the other hand, in the field activity level, experts involved in ODA have not disclosed their achievements. However, the article by Wada et al., which describes the contents of TEN MR (Minimum Requirement), shed light on Japan’s silent ODA community by disclosing Japan’s achievements in global health by drawing lessons that may be applicable to other countries. Our future challenge in the global health will be how to synthesize actions that reflect the lessons learnt from the field and which show scientific evidence using established methods.

In Lao People’s Democratic Republic (PDR), the mortality rate among children under 5 years of age is high (131 per 1000 live births in 2003), partly as a consequence of poor basic services provided by district hospitals. A simplified management tool, “Ten MR (Minimum Requirement)”, was developed in Lao PDR. The tool assured the quality of health services including the processes of planning, implementing, self-monitoring, supervision, reporting and evaluation. The tool focused on ten basic services, integrating stakeholders from district hospitals and governing agencies. Each district hospital develops feasible annual activities, assigning responsibility to people based on a consensus between hospital staff and local governing agencies. Hospitals can self-monitor their activities on a monthly basis. Supervisory visits to district hospitals by local governing agencies improved activities and communication between staff. Visualization of progress promoted the sharing of achievements between staff and highlighted activities in need of more work. In 2004, district hospitals in Vientiane and Oudomxay provinces initiated the application of the tool. These district hospitals included primary care hospitals for outpatients, emergency care and in-patients, with a capacity of 10–20 beds, providing care for a population of between 30,000 and 80,000 people. The Ministry of Health recognized the effectiveness of Ten MR and implemented the expansion of the tool to all district hospitals in Lao PDR from 2011. Ten MR benefits district hospitals and governing agencies. Ten MR focuses on the daily routine work, enhancing team work and communication among all stakeholders.

Background: Plasmodium, the causative agent of malaria, exports many proteins to the surface of the infected red blood cell (iRBC) in order to modify it toward a structure more suitable for parasite development and survival. One such exported protein, SURFIN_4.2, from the parasite of human malignant malaria, P. falciparum, was identified in the trypsin-cleaved protein fraction from the iRBC surface, and is thereby inferred to be exposed on the iRBC surface. SURFIN_4.2 also localize to Maurer’s clefts—parasite-derived membranous structures established in the RBC cytoplasm and tethered to the RBC membrane—and their role in trafficking suggests that they are a pathway for SURFIN_4.2 transport to the iRBC surface. It has not been determined the participation of protein domains and motifs within SURFIN_4.2 in transport from Maurer’s clefts to the iRBC surface; and herein we examined if the SURFIN_4.2 intracellular region containing tryptophan-rich (WR) domain is required for its exposure on the iRBC surface. Results: We generated two transgenic parasite lines which express modified SURFIN_4.2, with or without a part of the intracellular region. Both recombinant SURFIN_4.2 proteins were exported to Maurer’s clefts. However, only SURFIN_4.2 possessing the intracellular region was efficiently cleaved by surface treatment of iRBC with proteinase K. Conclusions: These results indicate that SURFIN_4.2 is exposed on the iRBC surface and that the intracellular region containing WR domain plays a role on the transport from Maurer’s clefts to the iRBC membrane.

For a long period Japan was a country with a variety of parasites linked to the geo-climatic features of the country and agricultural modes. However national endeavors to promote parasite controls resulted in the successful elimination of those parasites by around 1970. In this short article, I briefly overview the control programs of soil-transmitted parasites, lymphatic filaria, Schistosoma japonicum and malaria, and cite some of the characteristic features and remarkable facts revealed in the course of individual control programs.

Controversy persists as to whether helminth infections cause or protect against asthma and atopy. The aim of this study was to investigate the effects of helminth infection on asthma and atopy among Bangladeshi children. A total of 912 children aged 4.5 years (mean = 54.4, range = 53.5–60.8 months) participated in a cross-sectional study nested into a randomized controlled trial in Bangladesh. Ever-asthma, ever-wheezing and current wheezing were identified using the International Study of Asthma and Allergies in Childhood questionnaire. Current helminth infection was defined by the presence of helminth eggs in stools, measured by routine microscopic examination. Repeated Ascaris infection was defined by the presence of anti-Ascaris IgE≥0.70 UA/ml in serum measured by the CAP-FEIA method. Atopy was defined by specific IgE to house dust mite (anti-DP IgE) ≥0.70 UA/ml measured by the CAP-FEIA method and/or positive skin prick test (≥5 mm). Anti-Ascaris IgE was significantly associated with ever asthma (odds ratio (OR) = 1.86, 95% CI: 1.14–3.04, highest vs. lowest quartile; P for trend 0.016). Anti-Ascaris IgE was also significantly associated with positive anti-DP IgE (OR = 9.89, 95% CI: 6.52–15.00, highest vs. lowest; P for trend <0.001) and positive skin prick test (OR = 1.69, 95% CI: 1.01–2.81, highest vs. lowest, P for trend 0.076).These findings suggest that repeated Ascaris infection is a risk factor for asthma and atopy in rural Bangladeshi children. Further analysis is required to examine the mechanism of developing asthma and atopy in relation to helminth infection.

It has been demonstrated that continuous exposure to amodiaquine (AQ) alone elicits in vitro antischistosomal activities at concentrations of 1 - 10 µg/ml. However, orally administered drugs reach a peak blood concentration within one or two hours and then gradually decrease. The blood concentration does not remain at a constant level over several days as in vitro concentration of continuous drug exposure. In vitro activities by one day exposure to AQ better reflect the actual antischistosomal activities after oral administration than those elicited by continuous exposure.The objective of the present study is to compare the antischistosomal potential of one-day exposure to AQ with that to praziquantel (PZQ), a current antischistosomal drug. Schistosoma mansoni adult worm pairs were incubated with 0 (control), 1, 2, 5 and 10 µg/ml AQ as well as 0.01, 0.02, 0.05 and 0.1 µg/ml PZQ for the first day, and were subsequently incubated in drug-free media for a period of 14 days. The one-day exposure to AQ significantly reduced the daily egg output of the worm pairs at 1 - 10 µg/ml. The inhibitory effect on egg production continued at 5 and 10 µg/ml but proved temporary at 1 and 2 µg/ml. Furthermore, AQ-induced specific morphological alterations (severe swelling and/or localization of hemozoin) were observed in the worms at 5 and 10 µg/ml. The AQ-specific appearance of the male worms gradually faded during subsequent incubation in drug-free media, although the female worms showed elongation. Meanwhile, PZQ inhibited the egg output of adult worm pairs at concentrations of 0.01 - 0.1 µg/ml during exposure. The inhibitory effect on egg production continued at 0.05 and 0.1 µg/ml but proved temporary at 0.01 and 0.02 µg/ml. Furthermore, PZQ induced a visible contraction and shortening of the male and female worms at 0.05 and 0.1 µg/ml during exposure, but the PZQ-specific alterations quickly disappeared during subsequent incubation in drug-free media. To our knowledge, this is the first report showing that one-day exposure to AQ inhibits the egg production of adult worm pairs at 1 - 10 µg/ml and induces specific morphological alterations in the worms at 5 and 10 µg/ml. The present findings have important implications for the evaluation of the therapeutic effects of both AQ monotherapy and combination therapy with artesunate on schistosomiasis in clinical field trials.