1.Parasite controls in Japan with emphasis on special characteristics
Tropical Medicine and Health 2008;36(3SUPPLEMENT):S49-S67
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.
2.Ascaris lumbricoids infection as a risk factor for asthma and atopy in rural Bangladeshi children
Mohammad D. H. Hawlader ; Enbo Ma ; Emiko Noguchi ; Makoto Itoh ; Shams E. Arifeen ; Lars Å. Persson ; Sophie E. Moore ; Rubhana Raqib ; Yukiko Wagatsuma
Tropical Medicine and Health 2014;():-
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.
3.Comparison of the in vitro effects of one-day exposure to amodiaquine and praziquantel on Schistosoma mansoni adult worm pairs
Tropical Medicine and Health 2014;():-
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.
5.Current Trends of Immunization in Nigeria: Prospect and Challenges
Endurance A. Ophori ; Musa Y. Tula ; Azuka V. Azih ; Rachel Okojie ; Precious E. Ikpo
Tropical Medicine and Health 2014;():-
Immunization is aimed at the prevention of infectious diseases. In Nigeria, the National Programme on Immunization (NPI) suffersrecurrent setbacks due to many factorsincluding ethnicity and religious beliefs. Nigeria is made up of 36 states with its federal capital in Abuja. The country is divided into six geo-political zones; north central, north west, north east, south east, south west and south south. The population is unevenly distributed across the country. The average population density in 2006 was estimated at 150 people per square kilometres with Lagos, Anambra, Imo, Abia, and Akwa Ibom being the most densely populated states. Most of the densely populated states are found in the south east. Kanowith an average density of 442 persons per square kilometre, is the most densely populated state in the northern part of the country. This study presents a review on the current immunization programmeand the many challengesaffecting its success in the eradication of childhood diseases in Nigeria.
7.Treatment of parasitic skin diseases with dimeticones A new family of compounds with a purely physical mode of action
Tropical Medicine and Health 2014;():-
Epidermal parasitic skin diseases (EPSD) are common in the tropics and sub-tropics. They are caused by mites, lice and other blood-sucking insects. In resource-poor countries they are associated with considerable morbidity. Hitherto, EPSD are treated with insecticides with a neurotoxic mode of action. The efficacy of this treatment is variable, and the development and spread of resistant mites and lice is alarming. A new concept for treating EPSD is presented which is based on the topical application of dimeticones, silicone oils of low viscosity which rapidly kill insects and mites by a physical mode of action. They creep into the respiratory system and block oxygen supply. The physical mode of action makes the development of resistant parasite strains very unlikely. Due to their safety and efficacy, dimeticones are promising candidates for population-based intervention programmes targeted against EPSD in resource-poor settings.
8.Morbidity control of schistosomiasis by mass drug administration: How can we do it best and what will it take to move on to elimination?
Tropical Medicine and Health 2014;():-
The World Health Organization (WHO) has, for some time, encouraged countries endemic for schistosomiasis to control morbidity from this disease through mass drug administration (MDA) of the well-tolerated drug, praziquantel (PZQ).With the London Declaration in January 2012 and the promise by Merck Serono to eventually donate 250 million PZQ tablets per year, most endemic countries in sub-Saharan Africa have now developed national plans to do MDA for schistosomiasis morbidity control. More recently, based on two World Health Assembly (WHA) resolutions (WHA 54.19 & WHA 65.21) on schistosomiasis, countries are further encouraged to eliminate schistosomiasis, where feasible. The fight against schistosomiasis is therefore in a critical period of tremendous opportunities and equal challenges. How do we do the most effective job of MDA? What tools do we need to do this job better?How will we know when to move from morbidity control to elimination? What combinations of interventions, beyond MDA, are needed to eliminate transmission? The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) has its Secretariat at the University of Georgia and with programs in more than 24 institutions in 17 countries it is trying to answer these very practical questions through multiple large field-based studies and the evaluation or development of better diagnostics for schistosomiasis. This presentation will summarize the current status of morbidity control and elimination programs and the operational research by SCORE that we hope will provide much-needed answers for national program managers so they can most effectively pursue these critical public health programs.
9.About J-GRID (Japan Initiative for Global Research Network on Infectious Diseases)
Tropical Medicine and Health 2014;():-
Since infectious diseases heed no national borders, international research collaboration across borders must be enhanced. The Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan launched the J-GRID program in 2005, which consists of the two elements; (1) construction of collaboration centers in Asian and African countries on a reciprocal basis between a Japanese university/institution and a counterpart in the host country and (2) connecting those collaboration centers into a network and setting up its headquarters, CRNID. J-GRID initiated with 5 collaboration centers in 3 Asian countries has expanded to include 13 centers in 8 countries (6 in Asia and 2 in Africa). The aims of J-GRID include conducting high quality research on infectious diseases of regional and global importance, and advancing technologies and developing human resources in the field. In this way, J-GRID is expected to contribute to the public health of the host countries, our own country and the world. After the completion of the first start-up phase (2005–2009), J-GRID has stepped up its activity for the second phase (2010–2014). While the first phase was just like an incubation period, the second phase should be the exponential growth phase, maximizing its research activities. Indeed, J-GRID is now generating remarkable research outcomes with an increasing number of publications. The mid-term evaluation made by the MEXT in FY2012 commended J-GRID as an ideal model led by Japan, a world leader of science and technology, and highly recommended that the program be continued for years to come after 2014.
10.Population based cohort study for Pediatric Infectious Diseases research in Vietnam
Lay-Myint Yoshida ; Motoi Suzuki ; Vu Dinh Thiem ; Wolf Peter Smith ; Ataru Tsuzuki ; Vu Thi Thu Huong ; Kensuke Takahashi ; Masami Miyakawa ; Nguyen Thi Hien Anh ; Kiwao Watanabe ; Nguyen Thu Thuy Ai ; Le Huu Tho ; Paul Kilgore ; Hiroshi Yoshino ; Michiko Toizumi ; Michio Yasunami ; Hiroyuki Moriuchi ; Dang Duc Anh ; Koya Ariyoshi
Tropical Medicine and Health 2014;():-
A population-based cohort study on pediatric infectious diseases was established at Khanh Hoa Province, central Vietnam in 2006, to determine the etiology and risk factors for severe pediatric infectious diseases (SPID) such as acute respiratory infection (ARI), diarrhea and dengue which are the major causes of under 5 mortality. A population census survey was conducted in Nha-Trang and Ninh-Hoa to collect demographic, social-behavioral data and disease burden on SPID. The study site covered a population of 353,525 residing in 75,826 households with 24,781 children less than 5 years. Hospital databases from two hospitals covering the region were obtained. Linking the census and hospital databases, we were able to investigate on a variety of SPID such as environmental tobacco smoking exposure and increased risked of pediatric pneumonia hospitalization, population density, water supply and risk of dengue fever and animal livestock and risk of hospitalized diarrhea. To determine incidence, viral etiology and risk factors for pediatric ARI/pneumonia, we setup a population based prospective hospitalized Pediatric ARI surveillance at Khanh Hoa General Hospital, Nha-Trang in February 2007. The study has revealed RSV, rhinovirus and influenza A as major viral pathogens, role of multiple viral infection and its interaction with bacteria in the development of pneumonia. In addition, we are also conducting a birth cohort study to investigate the incidence of congenital infection and its impact on physical-neurological development, and role of host genetic polymorphism on SPID hospitalization in Vietnam. Population mobility, high cost of regular census update and low mortality are the challenges.