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One of the biggest concerns in the area of public health is caused by human intestinal parasites, which are found largely in tropical countries. The diagnosis of these parasitic diseases is done through physiological symptoms and fecal examination. Often, few professionals are available and able to perform this type of examination, which is considered time-consuming, requires trained personnel, prone to errors, and can cause eye strain in the specialist. In this paper, we investigate the use of the faster R-CNN object detection method to identify eggs of Schistosoma mansoni, forming a system to aid decision making in the diagnosis of fecal examination. A real database was built with 66 images prepared by the Kato–Katz method. Online and offline data augmentation techniques were used to obtain a larger number of samples. As a result, the proposed solution reached an average precision value of 0.765 for an IoU (intersection over union) of 0.50. The results and applicability of the system are promising and may be used in public health programs to assist health professionals in the diagnosis and monitoring of schistosomiasis in endemic areas. [ABSTRACT FROM AUTHOR]

Multiple schistosome and soil-transmitted nematode infections are frequently reported in human populations living in tropical areas of developing countries. In addition to exposure factors, the host immune response plays an important role in helminth control and morbidity in hosts with multiple infections; however, these aspects are difficult to evaluate in human populations. In the current study, female Swiss mice were simultaneously co-infected with Strongyloides venezuelensis and Schistosoma mansoni or infected with St. venezuelensis at 2, 4, or 14 weeks after Sc. mansoni infection. The simultaneously infected mice showed a similar parasite burden for St. venezuelensis compared with mono-infected mice. In contrast, there was a significant reduction of St. venezuelensis burden (primarily during the migration of the larvae) in mice that were previously infected with Sc. mansoni at the acute or chronic phase. Independent of the stage of Sc. mansoni infection, the St. venezuelensis co-infection was capable of inducing IL-4 production in the small intestine, increasing the IgE concentration in the serum and increasing eosinophilia in the lungs and intestine. This result suggests that the nematode infection stimulates local type 2 immune responses independently of the schistosomiasis stage. Moreover, previous Sc. mansoni infection stimulated early granulocyte infiltration in the lungs and trematode-specific IgM and IgG1 production that recognized antigens from St. venezuelensis infective larvae; these immune responses would act in the early control of St. venezuelensis larvae. Our data suggest that the effect of multiple helminth infections on host susceptibility and morbidity largely depends on the species of parasite and the immune response. [ABSTRACT FROM AUTHOR]