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SummaryWe used a rapid, visually read, field applicable monoclonal antibody (MoAb)-dipstick assay for specific diagnosis of urinary schistosomiasis together with microscopy to determine the prevalence of infant schistosomiasis in a community in the Awutu-Efutu Senya District in the Central Region of Ghana.The study group consisted of 97 infants (51 males and 46 females) aged 2 months to 5 years. A total of 75 of 97 (77.3%) subjects submitted stool samples; none had Schistosoma mansoni. Three individuals (3.1%) had hookworms but there were no other intestinal helminths. The urinary schistosomiasis prevalence by MoAb-dipstick (30%) was higher (P < 0.05) than that estimated by microscopy (11.2%). However, three of nine (33.3%) microscopically confirmed cases tested MoAb-dipstick positive after pre-treatment of the urine specimen with heat. The youngest infant to be found infected with S. haematobium microscopically was 4 months old. Fifteen of 71 S. haematobium egg negative individuals tested dipstick positive, giving a dipstick specificity of 78.9% as compared with microscopy as gold standard test. The relative sensitivity of the dipstick was 100%.

The prevalence of allergic and autoimmune diseases is increasing in developed countries, possibly due to reduced exposure to microorganisms in childhood (hygiene hypothesis). Epidemiological and experimental evidence in support of this hypothesis is accumulating. In this context, parasitic helminths are now important candidates for antiallergic/anti-inflammatory agents. Here we summarize antiallergic/anti-inflammatory effects of helminths together along with our own study of the effects of Schistosoma mansoni on Th17-dependent experimental arthritis. We also discuss possible mechanisms of helminth-induced suppression according to the recent advances of immunology.

Nippostrongylus brasiliensis infection is characterized by blood and tissue eosinophilia induced by interleukin (IL)-5 secreted from CD4+ T cells. However, it is still obscure whether eosinophils play an important role in the protection against N. brasiliensis infection. In this study we attempted to determine whether the in vivo environment of IL-5 transgenic mice, characterized by high eosinophil production, could affect the worm burden after N. brasiliensis infection. Kinetic studies on the infection demonstrated a significantly lower worm recovery from the intestine of IL-5 transgenic mice compared to age-matched background controls. This tendency was also observed at the lung stage of the infection. Furthermore, with respect to elevation of the serum IgE concentration, the peak level was observed at 2 weeks after infection in infected background control mice with four times higher concentrations than those of uninfected mice. In contrast, the increase of IgE concentration in IL-5 transgenic mice was very limited and low. The adoptive transfer of eosinophils from IL-5 transgenic mice into background control animals resulted in the reduction of worm recovery from the lungs, suggesting that eosinophils play a key role in the protection against migrating larvae of N. brasiliensis. These results indicate that the innate high level of eosinophils due to constitutive production of IL-5 augments immunity against N. brasiliensis infection.

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BackgroundAzithromycin (AZM) is a macrolide antibiotic that displays an excellent safety profile even in children and pregnant women and has been shown to have anti-malarial activity against blood stage Plasmodium falciparum. This study evaluated the transmission-blocking effect of AZM using a rodent malaria model.MethodsAZM-treated mice infected with Plasmodium berghei were exposed to Anopheles stephensi mosquitoes, followed by the observation of parasite development at different phases in the mosquito, i.e., ookinetes in the midgut, oocysts on the midgut, and sporozoites in the midgut and salivary glands. Furthermore, to evaluate the effect on organelle replication of each stage, quantitative real-time PCR analysis was performed.ResultsThe inhibitory effect of AZM was noticeable in both gametocyte-ookinete transformation in the midgut and sporozoite production in the oocyst, while the latter was most remarkable among all the developmental phases examined. Real-time PCR analysis revealed that AZM suppressed apicoplast replication at the period of sporozoite production in oocysts.ConclusionsAZM inhibits parasite development in the mosquito stage, probably through the same mechanism as in the liver and blood stages. Such a multi-targeting anti-malarial, along with its safety, would be ideal for mass drug administration in malaria control programmes.

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