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Premunity
Premunition, also known as infection-immunity, is a host response that protects against high numbers of parasite and illness without eliminating the infection. This type of immunity is relatively rapid, progressively acquired, short-lived, and partially effective. For malaria, premunition is maintained by repeated antigen exposure from infective bites. Thus, if an individual departs from an endemic area, he or she may lose premunition and become susceptible to malaria. Antibody action contributes to premunition. However, premunition is probably much more complex than simple antibody and antigen interaction. In the case of malaria, the sporozoite and merozoite stages of ''Plasmodium'' elicit the antibody response which leads to premunition. Immunoglobulin E targets the parasites and leads to eosinophil degranulation which releases major basic protein that damages the parasites, and other factors elicit a local inflammatory response. However, ''Plasmodium'' can change its surface ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Premunition
Premunition, also known as infection-immunity, is a host response that protects against high numbers of parasite and illness without eliminating the infection. This type of immunity is relatively rapid, progressively acquired, short-lived, and partially effective. For malaria, premunition is maintained by repeated antigen exposure from infective bites. Thus, if an individual departs from an endemic area, he or she may lose premunition and become susceptible to malaria. Antibody action contributes to premunition. However, premunition is probably much more complex than simple antibody and antigen interaction. In the case of malaria, the sporozoite and merozoite stages of ''Plasmodium'' elicit the antibody response which leads to premunition. Immunoglobulin E targets the parasites and leads to eosinophil degranulation which releases major basic protein that damages the parasites, and other factors elicit a local inflammatory response. However, ''Plasmodium'' can change its surface anti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunity (medical)
In biology, immunity is the capability of multicellular organisms to resist harmful microorganisms. Immunity involves both specific and nonspecific components. The nonspecific components act as barriers or eliminators of a wide range of pathogens irrespective of their antigenic make-up. Other components of the immune system adapt themselves to each new disease encountered and can generate pathogen-specific immunity. Immunity is a complex biological system that can recognize and tolerate whatever belongs to the self, and to recognize and reject what is foreign (non-self). Innate and adaptive Innate Immunity First off, the immune system is a system in the body of animals that enables animals to avoid or limit many infections caused by pathogens. Pathogens are disease causing agents, causing a wide range of illnesses. As for Diseases it's when structure of an organism is negatively affected other than external injury. Both diseases and pathogens affect the immune system causing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herd Immunity
Herd immunity (also called herd effect, community immunity, population immunity, or mass immunity) is a form of indirect protection that applies only to contagious diseases. It occurs when a sufficient percentage of a population has become immune to an infection, whether through previous infections or vaccination, thereby reducing the likelihood of infection for individuals who lack immunity. Once the herd immunity has been reached, disease gradually disappears from a population and may result in eradication or permanent reduction of infections to zero if achieved worldwide. Herd immunity created via vaccination has contributed to the reduction of many diseases. Effects Protection of those without immunity Some individuals either cannot develop immunity after vaccination or for medical reasons cannot be vaccinated. Newborn infants are too young to receive many vaccines, either for safety reasons or because passive immunity renders the vaccine ineffective. Individuals who ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichomonas Gallinae
''Trichomonas gallinae'' is a cosmopolitan parasite of birds including finches, pigeons, doves, turkeys, chickens, parrots, raptors ( hawks, golden eagle, etc.). The condition in birds of prey is called frounce.Kennedy, Murry J. "Trichomoniasis in Birds" Food Safety Division, Alberta Agriculture and Food. http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex4444 It is believed to be an ancient pathogen causing frounce-like symptoms in theropod dinosaurs. The same condition in pigeons is commonly called canker. The protozoa are small (5 to 20 µm size) oval or spherical flagellates with four free flagella found on the anterior aspect of the parasite. They also have an axostyle found on the posterior end as well as an undulating membrane on one side. An important diagnostic feature is the lack of a free posterior flagellum. Life cycle ''T. gallinae'' is found in a motile trophozoite and nonmotile pseudocyst stage. It is generally found in the oral-nasal cavity or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Onchocerca Volvulus
''Onchocerca volvulus'' is a filarial (arthropod-borne) nematode (roundworm) that causes onchocerciasis (river blindness), and is the second-leading cause of blindness due to infection worldwide after trachoma. It is one of the 20 neglected tropical diseases listed by the World Health Organization, with elimination from certain countries expected by 2020. John O’Neill, an Irish surgeon, first described ''Onchocerca volvulus'' in 1874, when he found it to be the causative agent of ‘craw-craw’, a skin disease found in West Africa. A Guatemalan doctor, Rodolfo Robles, first linked it to visual impairment in 1917. ''O. volvulus'' is primarily found in sub-Saharan Africa, and humans are the only known definitive host; there is also disease transmission in some South American nations, as well as Yemen (see global map bottom right). It is spread from person to person via female biting blackflies of the genus '' Simulium''. Morphology ''O. volvulus'' parasites obtain nutrie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Babesiosis
Babesiosis or piroplasmosis is a malaria-like parasitic disease caused by infection with a eukaryotic parasite in the order Piroplasmida, typically a ''Babesia'' or '' Theileria'', in the phylum Apicomplexa. Human babesiosis transmission via tick bite is most common in the Northeastern and Midwestern United States and parts of Europe, and sporadic throughout the rest of the world. It occurs in warm weather. People can get infected with ''Babesia'' parasites by the bite of an infected tick, by getting a blood transfusion from an infected donor of blood products, or by congenital transmission (an infected mother to her baby). Ticks transmit the human strain of babesiosis, so it often presents with other tick-borne illnesses such as Lyme disease. After trypanosomes, ''Babesia'' is thought to be the second-most common blood parasite of mammals. They can have major adverse effects on the health of domestic animals in areas without severe winters. In cattle the disease is known as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast, it shares land borders with Pakistan to the west; China, Nepal, and Bhutan to the north; and Bangladesh and Myanmar to the east. In the Indian Ocean, India is in the vicinity of Sri Lanka and the Maldives; its Andaman and Nicobar Islands share a maritime border with Thailand, Myanmar, and Indonesia. Modern humans arrived on the Indian subcontinent from Africa no later than 55,000 years ago., "Y-Chromosome and Mt-DNA data support the colonization of South Asia by modern humans originating in Africa. ... Coalescence dates for most non-European populations average to between 73–55 ka.", "Modern human beings—''Homo sapiens''—originated in Africa. Then, interm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitemia
Parasitemia is the quantitative content of parasites in the blood. It is used as a measurement of parasite load in the organism and an indication of the degree of an active parasitic infection. Systematic measurement of parasitemia is important in many phases of the assessment of disease, such as in diagnosis and in the follow-up of therapy, particularly in the chronic phase, when cure depends on ascertaining a parasitemia of zero. The methods to be used for quantifying parasitemia depends on the parasitic species and its life cycle. For instance, in malaria, the number of blood-stage parasites can be counted using an optical microscope, on a special thick film (for low parasitemias) or thin film blood smear (for high parasitemias). The use of molecular biology Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infection
An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable disease, is an illness resulting from an infection. Infections can be caused by a wide range of pathogens, most prominently bacteria and viruses. Hosts can fight infections using their immune system. Mammalian hosts react to infections with an innate response, often involving inflammation, followed by an adaptive response. Specific medications used to treat infections include antibiotics, antivirals, antifungals, antiprotozoals, and antihelminthics. Infectious diseases resulted in 9.2 million deaths in 2013 (about 17% of all deaths). The branch of medicine that focuses on infections is referred to as infectious disease. Types Infections are caused by infectious agents (pathogens) including: * Bacteria (e.g. '' Mycobacterium tubercul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rickettsia
''Rickettsia'' is a genus of nonmotile, gram-negative, nonspore-forming, highly pleomorphic bacteria that may occur in the forms of cocci (0.1 μm in diameter), bacilli (1–4 μm long), or threads (up to about 10 μm long). The term "rickettsia" has nothing to do with rickets (which is a deficiency disease resulting from lack of vitamin D); the bacterial genus ''Rickettsia'' instead was named after Howard Taylor Ricketts, in honor of his pioneering work on tick-borne spotted fever. Properly, ''Rickettsia'' is the name of a single genus, but the informal term "rickettsia", plural "rickettsias", usually not capitalised, commonly applies to any members of the order Rickettsiales. Being obligate intracellular bacteria, rickettsias depend on entry, growth, and replication within the cytoplasm of living eukaryotic host cells (typically endothelial cells). Accordingly, ''Rickettsia'' species cannot grow in artificial nutrient culture; they must be grown either in tissue or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protozoan Infection
Protozoan infections are parasitic diseases caused by organisms formerly classified in the kingdom Protozoa. They are usually contracted by either an insect vector or by contact with an infected substance or surface and include organisms that are now classified in the supergroups Excavata, Amoebozoa, SAR, and Archaeplastida. Protozoan infections are responsible for diseases that affect many different types of organisms, including plants, animals, and some marine life. Many of the most prevalent and deadly human diseases are caused by a protozoan infection, including African sleeping sickness, amoebic dysentery, and malaria. The species originally termed "protozoa" are not closely related to each other and only have superficial similarities (eukaryotic, unicellular, motile, though with exceptions). The terms "protozoa" (and protist) are usually discouraged in the modern biosciences. However, this terminology is still encountered in medicine. This is partially because of the co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogen
In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term ''pathogen'' came into use in the 1880s. Typically, the term ''pathogen'' is used to describe an ''infectious'' microorganism or agent, such as a virus, bacterium, protozoan, prion, viroid, or fungus. Small animals, such as helminths and insects, can also cause or transmit disease. However, these animals are usually referred to as parasites rather than pathogens. The scientific study of microscopic organisms, including microscopic pathogenic organisms, is called microbiology, while parasitology refers to the scientific study of parasites and the organisms that host them. There are several pathways through which pathogens can invade a host. The principal pathways have different episodic time frames, but soil has the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
