Parasitic diseases host-parasite relationships

Because it is an infection with a very long natural history, the host-parasite relationships have become extremely complex, involving far-reaching changes on both sides, interfering with the development of the infection. Thus, the process of natural selection that acts continuously on the protozoa leads to a parasite diversity that influences the severity of the disease. 

General - A compendium of chemotherapeutic agents for parasitic protozoa and helminths of dogs and cats was published. Host-parasite relationships were reviewed.2 The proceedings of an international conference on chemotherapeutic agents for parasitic diseases appeared.3 Nucleoside analogs as antiparasitic agents were reviewed.4... 

Trouet A, Jadin JM, Hoof FV. Lysosomotropic chemotherapy in protozoal diseases. In Biochemistry of Parasites and Host-Parasites Relationships. Amsterdam, The Netherlands North-HoUand, 1976 519. 

The direct effects of acidic precipitation on vegetation have been characterized by a number of researchers.Visible injury typically has been described as small necrotic lesions. The significance of these small lesions to host-parasite relationships has been discussed by Shriner. Disease incidence was shown to increase as a function of plant exposure to simulated acidic rain of pH 3.2, especially in the case of facultative parasites, which are most successful as pathogens when using breeches in host defense as... 

This concept of the mutually adjuvant effects of malnutrition and infestation seems so eminently reasonable and logical, and the common coexistence of poor nutritional status with a high incidence of such diseases as malaria, ancylostomiasis, and schistosomiasis seems to offer such obvious pnmo facie evidence for its truth, that it is perhaps not surprising that the detailed evidence on which it is based has not often been critically evaluated. It is the purpose of this paper to attempt to assess, without any iconoclastic intent, whether the evidence for these and similar assertions justifies the confidence with which they have been made, and to determine how far it is possible at present to formulate any broad generalizations about this aspect of host-parasite relationships. 

Staphylococci exist in air, dust, sewage, water, milk, and food or on food equipment, environmental surfaces, humans, and animals. Normally, this species lives in the human oropharynx, nose, large intestine, vagina, and on the skin without causing harm. However, if a breach in the skin or mucosal barrier occurs, S. aureus gains access to nearby tissues or the bloodstream where it can colonize and cause disease. The relationship between S. aureus and its human host, then, is dynamic in nature, capable of quickly shifting from mutualistic or commensualistic to parasitic. 

Unlike most other types of infection, protozoan diseases are often chronic, lasting for months to years. When associated with a strong host immune response, this type of long-term infection is apt to result in a high incidence of immunopathology. Until recently the importance of host immune response in controlling many parasite infections was not fully appreciated, but the impact of HIV infection on many parasitic diseases has highlighted this relationship. 

Luttrell, E.S. (1974) Parasitism of fungi on vascular plants. Mycologia, 66,1-15. Luttrell, E.S. (1977) The disease cycle and fungus-host relationships in dallisgrass ergot. Phytopathology, 67,1461-1468. 

Multiple species of bacteria, protozoa, and fungi can inhabit a human body. Their biological relationship with the host can be described as symbiosis (mutualism), commensalism, and parasitism, while the medium modification can trigger a relationship change. For example, an infection or an invasive procedure can inflict the embedded microbes to shift the microbiotic balance some diseases and treatments promote immune variations embedding devices into the body often causes a tissue alteration. The nature of a device interaction with medium and microbiota is evidently crucial for both device functioning and microbiota behavior. 

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