Impact Of Helminth Infections Research Articles

Filarial/Human Immunodeficiency Virus Coinfection in Urban Southern India

The disease course of human immunodeficiency virus (HIV) is often altered by existing or newly acquired coinfections. Treatment or prevention of these concomitant infections often improves the quality and duration of life of HIV-infected persons. The impact of helminth infections on infections with HIV is less clear. However, HIV is frequently most problematic in areas where helminth infections are common. In advance of the widespread distribution of drugs for elimination of lymphatic filariasis, we assessed the prevalence of active Wuchereria bancrofti infection among HIV-positive patients in Chennai, India at two time points separated by four years. We found that the overall prevalence of W. bancrofti infections among HIV-positive persons was 5-9.5%, and there were no quantitative differences in circulating filarial antigen levels between HIV-positive and HIV-negative filarial-infected patients.

Helminth Infection withLitomosoides sigmodontisInduces Regulatory T Cells and Inhibits Allergic Sensitization, Airway Inflammation, and Hyperreactivity in a Murine Asthma Model

Numerous epidemiological studies have shown an inverse correlation between helminth infections and the manifestation of atopic diseases, yet the immunological mechanisms governing this phenomenon are indistinct. We therefore investigated the effects of infection with the filarial parasite Litomosoides sigmodontis on allergen-induced immune reactions and airway disease in a murine model of asthma. Infection with L. sigmodontis suppressed all aspects of the asthmatic phenotype: Ag-specific Ig production, airway reactivity to inhaled methacholine, and pulmonary eosinophilia. Similarly, Ag-specific recall proliferation and overall Th2 cytokine (IL-4, IL-5, and IL-3) production were significantly reduced after L. sigmodontis infection. Analysis of splenic mononuclear cells and mediastinal lymph nodes revealed a significant increase in the numbers of T cells with a regulatory phenotype in infected and sensitized mice compared with sensitized controls. Additionally, surface and intracellular staining for TGF-beta on splenic CD4(+) T cells as well as Ag-specific TGF-beta secretion by splenic mononuclear cells was increased in infected and sensitized animals. Administration of Abs blocking TGF-beta or depleting regulatory T cells in infected animals before allergen sensitization and challenges reversed the suppressive effect with regard to airway hyperreactivity, but did not affect airway inflammation. Despite the dissociate results of the blocking experiments, these data point toward an induction of regulatory T cells and enhanced secretion of the immunomodulatory cytokine TGF-beta as one principle mechanism. In conclusion, our data support the epidemiological evidence and enhance the immunological understanding concerning the impact of helminth infections on atopic diseases thus providing new insights for the development of future studies.

Parasitological aspects and biochemical changes of infected cultured tilapia (Oreochromis hybrid)

Background. Fish farming has been developed due to decline of traditional fishing where tilapia culture is one of the principal sources for fish production. This study was aimed to investigate the prevalence and impact of helminth infection on the health of cultured hybrid tilapia, Oreochromis sp.Materials and methods. Prevalence and intensity of helminth infection and histopathological response of infected organs were studied. Changes of biochemical composition, and protein electrophoritic pattern, and heavy metals levels of liver and muscle tissues were determined.Results. Helminth infection was restricted to the liver of 60% of the examined fish. Of this number 33% were infected by undifferentiated nematode larvae and heterophyid metacercariae while 67% showed the metacercarial infection only. Infection caused a noticeable alternation in histological architecture of the liver that was accompanied by depletion in hepatic glycogen, total lipids, and total protein. Moreover, biochemical components of the muscle tissues were significantly decreased along with intensity of infection. Protein fractions of the liver and muscle tissues were highly variable. Intensity of the parasitic infection was directly correlated with Fe and Mn levels in both liver and muscle.Conclusion. s. Cultured fish also suffered from helminth infection that significantly impaired the health and condition of fish as shown by histopathological, biochemical, and protein fractions changes recorded in this study. In additions, intensity of helminth infection might increase the capacity of infected organs in accumulation of heavy metals.

Helminth infections, morbidity indicators and schistosomiasis treatment history in three villages, Dongting Lake region, PR China

In order to estimate the public health impact of helminth infections, and to provide baseline data for interventions, parasitological and morbidity surveys were conducted among inhabitants of three villages in Dongting Lake region, Hunan Province, China. Ascaris lumbricoides was found to be the most common helminth infection, followed by Trichuris trichiura and Schistosoma japonicum. Left liver enlargement was the most common indicator of morbidity. Observed numbers of multiple species infections closely correlated with expected figures generated from a simple probabilistic model. Heterogeneity was observed in age and sex-standardized infection and morbidity prevalences among the villages and occupations. Males had higher levels of infection, were more likely to suffer morbidity, and were more likely to have been treated for schistosomiasis than women. The prevalence of each morbidity indicator was positively correlated with the number of times of treatment for schistosomiasis, and negatively correlated with number of years since last treatment. The results imply that treatment history for S. japonicum infection may be a good indicator of current morbidity risk.

Book Review: Impact of Helminth Infections on Human Nutrition

Book Review: Impact of Helminth Infections on Human Nutrition

Impact of Helminth Infections on Human Nutrition

Impact of Helminth Infections on Human Nutrition