Particle infection

We may know about different types of chemical compound and chemicals, Ultraviolet radiations, toxic elements how significantly causes harmful effect on body cells and causes diseases. But these types of diseases are not grouped into infectious disease. Because, infection have certain type of properties and in general view the responsible substance should have some specifi function within the body that is similar with the function of living organism.
Discovery of new class of particles provide us few new conception about life and living organism and few new conception about non livings. Not only that these particles also introduced new idea in medical science. There found two particles that somewhat similar with virus, but exactly these are not virus. These are nonliving particles. These two particles are Viriods and Prions. It an wonderful topics that these two particles can causes infectious disease. Hence, the definition of infectious disease should modify in medical science. In general conception of infection in medical science is usually agreed as cell affected and damaged by microorganism, such as virus and bacteria. When harmful bacteria enter into body, take part in reproduction into body and produce a huge quantity of new generation. Ultimately these increased level of harmful microorganism causes damage of cells. Hence, this phenomenon we termed as infection. Microorganism entering into body, taking part of these organisms own reproduction, we can never termed as infection until damage of cell of hosts. In our human body there have an abundance of microorganism these are not harmful, rather useful. These are called normal flora Not every kind of cell damage by foreign substance is termed as infection. Not only that only damage of cell is not a standard of defining infection. Body cell can damaged by chemical effect that we can not termed as infection. Again cell damage is not only indicator of defining infection. The person who is suffering from AIDS infected by HIV, happened directly damage of antibody. But we termed AIDS as an infectious disease. Infection can difference from other kinds of cell damage or other type of disorder within body. Infection have certain types of characteristics. Most important is that it causes by entering foreign particles into body, these substance are found to increasing their member in numbers into hosts body by any process and finally caused a harmful effect. In generally, a wide range of medical science is occupied by infection as caused by living microorganism. These microorganisms are found to increase the generation into body by different types of reproduction process. But discovery of Viriods and prions provide us an conception that non living particles also can causes infection. Viriods and prions Viriods and prions are nonliving particles similar with virus, but having no characteristics of living organism. These particles have significant ability of causes infectious disease of animals and plants. Viriods causes infections of plants. For example potatos, tomatos and apples are infects by viriods. Viriods have single strained RNA with no capsid. After entering into cell viriod can increase their number into cell by synthesis process. The abundance of viriods into cell disrupt the metabolism of plant cell. American scientist Stanley Prusiner in 1972, when start his work to investigate the cause Scrapie disease in sheep. He found an abnormal type of particle which is no DNA or RNA like Virus. These particles only have protein. When prions entered into body it starts to produce protein clump. These clumps induces normal protein into new prions. By this process prions increases their number in host body. Very common disease caused by prions infection is Mad cow disease and Creutzfeldt disease. Human also can develop such kinds of disease if human infect by prions.