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Some field trials have already demonstrated the high antischistosomal potential of combination therapies using Artesunate (ART) and current antimalarial drugs (Boulanger et al., 2007; Mohamed et al., 2009; Sissoko et al., 2009). The antischistosomal effects of these drugs are noteworthy, especially when they are used for the treatment of malaria in schistosomiasis endemic areas. However, the antischistosomal effects of Amodiaquine (AQ), Primaquine (PQ), Chloroquine (CQ) and Pyrimethamine (Py) have never been assessed by in vitro incubation. The objective of the present study is to assess the in vitro effects of current antimalarial drugs on the egg productivity of adult worm pairs of S. mansoni and their survival times. The effect of the current antimalarial drugs Mefloquine (MQ), quinine (QN), AQ, PQ, CQ, Sulfadiazine (Sf) and Py on the egg output of adult worm pairs of Schistosoma mansoni and their survival times during in vitro culture were assessed at a concentration of 10 Μg⁄ml. AQ, PQ, CQ and Py significantly inhibited the daily egg output of paired female worms at a concentration of 10 Μg⁄ml during the 1 or 2-day in vitro cultivation. However, QN and Sf did not significantly affect the daily egg output during the 8-day incubation. One-day exposure to MQ killed all paired male and female adult worms. AQ and PQ significantly decreased the survival of both paired male and female worms during the 14-day incubation, but QN, CQ, Py and Sf did not exert any similar effect. The present result is consistent with an assessment of the antischistosomal effects of artemisinin-based combination therapy in malaria and schistosomiasis co-endemic areas.

Contamination of water and air by soil-transmitted helminth eggs was investigated in a small village located in the suburbs of Hanoi, Vietnam. Water samples were collected from 29 households, two schools, two kindergartens, one restaurant, three ponds and 23 ditch sites during the rainy season. Water samples were also collected at the same places, except for one household and one restaurant, during the dry season. The water samples collected from households, schools, kindergartens and restaurant were comprised of well-water and rain-water. These samples included both water filtrated with sand and gravel and non-filtrated water. Two-liter water samples were examined for helminth eggs by either a centrifugation or flotation method. The contamination of air by helminth eggs was assessed by the method of Kroeger et al. (1992). Eggs in air were trapped on adhesive tapes hanging in rooms and in the area around 29 houses, two schools, two kindergartens, one restaurant and 18 utility poles. Out of 63 water samples collected from households in the rainy season, helminth eggs were found in four water samples; one from non-filtrated well-water and three from filtrated well-water samples. The one non-filtrated water sample contained six eggs of Toxocara sp., while the three filtrated water samples contained one egg each of Trichuris sp., Trichiuris sp. and Taenia sp. No eggs were found in the water samples collected from schools, kindergartens or the restaurant in the rainy season. All water samples collected from ponds and ditches in the rainy season contained many helminth eggs. The eggs found were Ascaris sp., Trichuris sp., Toxocara sp., Ascaridia galli, hookworm, Taenia sp. and Fasciola sp. Examination of the adhesive tapes hanging in the air showed that four sites were contaminated by helminth eggs, i. e. one site near the house, two sites near the school and one site at a utility pole. The species of eggs found were Trichuris sp., Ascaridia galli and Taenia sp. The number of eggs found on tapes was only one or two. In the dry season, a few samples of well-water and rain-water collected from the residential area were contaminated with helminth eggs, and all samples collected from ponds and ditches contained many eggs of various species similar to those collected in the rainy season. The present study clearly indicates that, in our study area, the villagers were subject to infection from soil-transmitted helminthes directly and indirectly through water.

This article reviews the main health education approaches for the control of urinary schistosomiasis which is endemic in many developing countries. The control of schistosomiasis by mass-chemotherapy and safe water supply needs people's behavioural changes through simultaneous effective health education. The characteristics of the following five health education approaches were demonstrated; (1) the 'provision of knowledge' approach, (2) the KAP (knowledge, attitude, and practice) or KAPB (knowledge, attitude, perception, and behaviour) study-based approach, (3) the health belief model, (4) the PRECEDE/PROCEED model, and (5) the community participation approach through empowerment and health learning. Education should be orientated by KAPB studies. Then, information on people's perception and attitudes toward the targeted disease should be collected through communication and discussion with people based on the Health Belief model. In the next step, proper knowledge and message for behavioural changes and disease control should be provided in a culturally acceptable and effective manner. These core parts of health education should be backed up using findings of the PRECEDE/PROCEED model. At the same time, health education should stimulate community participation, which in turn enhances the health learning process of community members. All these processes with available public health and basic human services should work together for effective behavioural change and for better health outcomes such as increasing mass-chemotherapy participation, Acta medica Nagasakiensia. 1998, 43(3-4), p.1-11

The study was carried out to determine the geographical distribution of Schistosoma haematobium infection in Kwale district, Kenya in 1981. Urine specimens were obtained from the pupils of the standard 4, 5 and 6 in 41 schools selected from 135 schools in Kwale district. Out of 2638 children, the ova of S. haematobium were detected in 41.2% by centrifugation of urine suggesting the widespread distribution of S. haematobium in the district. The infection rate was significantly higher in males than in females. Among four administrative divisions, the highest infection rate was observed in Kinango and a high endemic area was also found in Southern division. The infection rates in Kubo and Central divisions were relatively low. S. haematobium infection was highly prevalent in the southern part of coastal area in Kenya.

The effectiveness of the leaf extracts of Azadirachta indica (neem tree) against two nematodes, Angiostrongylus cantonensis and Trichinella spiralis was investigated in mice. Laboratory mice were inoculated with the nematodes followed by the oral administration of the leaf extracts. Two standard drugs, flubendazole and mebendazole were compared with the plant extract in the study. No significant effects of the leaf extract against the nematodes were observed. Thus, although the extract has been shown by other investigators to be animalarial, antibacterial and antifungal, no activity was observed against the two nematodes in this study.

The study was carried out to determine the geographical distribution of intestinal parasitic infection in Kwale district, Kenya in 1981. Stool specimens were obtained from the school children and were examined for the presence of both helminth ova and protozoan cysts. Entamoeba coli, Ascaris lumbricoides, hookworm and Trichuris trichiura were found to be common in the area. The prevalence of ascariasis and trichuriasis showed similar geographical distribution among divisions. The prevalence were high in both Central and Southhern but relatively low in Kinango and Kubo divisions. However, the geographical distribution of prevalence of E. coli and hookworm infections were different from those of ascariasis and trichuriasis. These results might reflect the differences of the population densities, the water sources and the sanitary conditions., 熱帯医学 Tropical medicine 39(2). p57-64, 1998

In order to investigate efficacy of praziquantel (biltricide) on morbidity related to Schistosoma haematobium infection, 300 subjects of which 219 had eggs in the urine were examined for urinary eggs, blood and protein before and three months after treatment. Haematuria and proteinuria disappeared in 80.4% and 75.5% of the studied subjects respectively. The disappearance rates were not related to pre-treatment levels of haematuria and proteinuria. The rates both for haematuria and proteinuria were significantly lower in the age group 15 years and over than in the younger age group. Parasitologically, praziquantel cured 85.3% of the egg positives and reduced the mean egg count by 98.2%., 熱帯医学 Tropical medicine 35(2). p83-90, 1993

A microscopic examination of a faecal specimens was designed to identify the enteropathogenic parasites in the diarrhoeal stool specimens in which neither enteropathogenic bacteria nor rotavirus was isolated in Caost Provincial General Hospital, Mombasa, Kenya. The parasites incriminated as causes of diarrhoea were Entamoeba histolytica, Giardia lamblia, Trichuris trichiura, hookworm and Ascaris lumbricoides. The cysts and ova of these parasites, however, were present with equal frequency in diarrhoeal, semi-formed and formed stool specimens, except the trophozoites of E. histolytica. The role of parasites in causation of diarrhoea is difficult to evaluate by the routine stool examination for parasites., 熱帯医学 Tropical medicine 35(1). p11-16, 1993

The hatchability of Schistosoma haematobium eggs excreted by patients treated with praziquantel (PZQ) was examined. The rate of hatching of the eggs excreted by the patients before treatment was 90.1%. The rates of hatching of the eggs excreted by the patients 3 hr, 24 hr and 48 hr after treatment were 25.5%, 19.2% and 29.9% respectively. In vivo PZQ inhibits the hatching of S. haematobium eggs. The result of in vivo experiment was strongly supported by the results of the in vitro experiments. The hatching of the eggs exposed to PZQ at a concentration of 0.1μg/ml for one hour in vitro was inhibited., 熱帯医学 Tropical medicine 35(1). p17-21, 1993

Side effects of praziquantel in a single-dose treatment of urinary schistosomiasis at 40 mg/kg were studied on 174 subjects by means of questioning clinical manifestations before and 24 hr after treatment. The numbers of abdominal pain/discomfort, nausea/vomiting and dizziness/lassitude increased after treatment at a statistically significant level. "Possible" side reactions, defined as clinical manifestations developed newly or increased their degree of severity after treatment, were experienced by 55.7% of the treated people. Females suffered more nausea/vomiting than males, and people of age 16-20 years had reactions more frequently than the other ages. With a few exceptions, the adverse effects were mild and disappeared within 11 hr after their onset., 熱帯医学 Tropical medicine 34(3). p91-96, 1992

The break of the eggshell formed by water- and praziquantel (PZQ)-induced hatching of Schistosoma mansoni eggs was observed by scanning electron microscopy. The break most frequently formed on the long axis of the eggshell opposite the spine, and less frequently along spine side, parallel or oblique to the long axis of the lateral side of the egg-shell. An outwardly-curled lip of shell lined the external margins of the hatching orifice. The shell itself was of uniform thickness and fairly smooth. No significant difference was observed in the position breaks between water- and PZQ-hatched eggs. However, PZQ hatching produced smaller hatching orifices and the miracidium frequently failed to escape., 熱帯医学 Tropical medicine 34(1). p9-14, 1992