|
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 tube ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staphylococcus Aureus
''Staphylococcus aureus'' is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often positive for catalase and nitrate reduction and is a facultative anaerobe that can grow without the need for oxygen. Although ''S. aureus'' usually acts as a commensal of the human microbiota, it can also become an opportunistic pathogen, being a common cause of skin infections including abscesses, respiratory infections such as sinusitis, and food poisoning. Pathogenic strains often promote infections by producing virulence factors such as potent protein toxins, and the expression of a cell-surface protein that binds and inactivates antibodies. ''S. aureus'' is one of the leading pathogens for deaths associated with antimicrobial resistance and the emergence of antibiotic-resistant strains, such as methicillin-resistant ''S. aureu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogenic Bacteria
Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often beneficial but others can cause infectious diseases. The number of these pathogenic species in humans is estimated to be fewer than a hundred. By contrast, several thousand species are part of the gut flora present in the digestive tract. The body is continually exposed to many species of bacteria, including beneficial commensals, which grow on the skin and mucous membranes, and saprophytes, which grow mainly in the soil and in decaying matter. The blood and tissue fluids contain nutrients sufficient to sustain the growth of many bacteria. The body has defence mechanisms that enable it to resist microbial invasion of its tissues and give it a natural immunity or innate resistance against many microorganisms. Pathogenic bacteria are specially adapted and endowed with mechanisms for overcoming the n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycosis
Fungal infection, also known as mycosis, is disease caused by fungi. Different types are traditionally divided according to the part of the body affected; superficial, subcutaneous, and systemic. Superficial fungal infections include common tinea of the skin, such as tinea of the body, groin, hands, feet and beard, and yeast infections such as pityriasis versicolor. Subcutaneous types include eumycetoma and chromoblastomycosis, which generally affect tissues in and beneath the skin. Systemic fungal infections are more serious and include cryptococcosis, histoplasmosis, pneumocystis pneumonia, aspergillosis and mucormycosis. Signs and symptoms range widely. There is usually a rash with superficial infection. Fungal infection within the skin or under the skin may present with a lump and skin changes. Pneumonia-like symptoms or meningitis may occur with a deeper or systemic infection. Fungi are everywhere, but only some cause disease. Fungal infection occurs after spores a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virus
A virus is a wikt:submicroscopic, submicroscopic infectious agent that replicates only inside the living Cell (biology), cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,Dimmock p. 4 more than 9,000 virus species have been described in detail of the millions of types of viruses in the environment. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. The study of viruses is known as virology, a subspeciality of microbiology. When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent particles, or ''virions'', consisti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflammation
Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving immune cells, blood vessels, and molecular mediators. The function of inflammation is to eliminate the initial cause of cell injury, clear out necrotic cells and tissues damaged from the original insult and the inflammatory process, and initiate tissue repair. The five cardinal signs are heat, pain, redness, swelling, and Functio laesa, loss of function (Latin ''calor'', ''dolor'', ''rubor'', ''tumor'', and ''functio laesa''). Inflammation is a generic response, and therefore it is considered as a mechanism of innate immune system, innate immunity, as compared to adaptive immune system, adaptive immunity, which is specific for each pathogen. Too little inflammation could lead to progressive tissue destruction by the harmful stimulus (e.g. b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycobacterium Tuberculosis
''Mycobacterium tuberculosis'' (M. tb) is a species of pathogenic bacteria in the family Mycobacteriaceae and the causative agent of tuberculosis. First discovered in 1882 by Robert Koch, ''M. tuberculosis'' has an unusual, waxy coating on its cell surface primarily due to the presence of mycolic acid. This coating makes the cells impervious to Gram staining, and as a result, ''M. tuberculosis'' can appear weakly Gram-positive. Acid-fastness, Acid-fast stains such as Ziehl–Neelsen stain, Ziehl–Neelsen, or Fluorescence, fluorescent stains such as Auramine O, auramine are used instead to identify ''M. tuberculosis'' with a microscope. The physiology of ''M. tuberculosis'' is highly aerobic organism, aerobic and requires high levels of oxygen. Primarily a pathogen of the mammalian respiratory system, it infects the lungs. The most frequently used diagnostic methods for tuberculosis are the Mantoux test, tuberculin skin test, Acid-Fast Stain, acid-fast stain, Microbiological cultu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy, treatment and antibiotic prophylaxis, prevention of such infections. They may either bactericide, kill or bacteriostatic agent, inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the common cold or influenza; drugs which inhibit viruses are termed antiviral drugs or antivirals rather than antibiotics. Sometimes, the term ''antibiotic''—literally "opposing life", from the Greek language, Greek roots ἀντι ''anti'', "against" and βίος ''bios'', "life"—is broadly used to refer to any substance used against microbes, but in the usual medical usage, antibiotics (such as penicillin) are those produced naturally (by one microorgani ... [...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] |
Viral Disease
A viral disease (or viral infection) occurs when an organism's body is invaded by pathogenic viruses, and infection, infectious virus particles (virions) attach to and enter susceptible cells. Structural Characteristics Basic structural characteristics, such as genome type, virion shape and replication site, generally share the same features among virus species within the same family. * Double-stranded DNA families: three are non-enveloped (''Adenoviridae'', ''Papillomaviridae'' and ''Polyomaviridae'') and two are enveloped (''Herpesviridae'' and ''Poxviridae''). All of the non-enveloped families have icosahedral capsids. * Partly double-stranded DNA viruses: ''Hepadnaviridae''. These viruses are enveloped. * One family of single-stranded DNA viruses infects humans: ''Parvoviridae''. These viruses are non-enveloped. * Positive single-stranded RNA families: three non-enveloped (''Astroviridae'', ''Caliciviridae'' and ''Picornaviridae'') and four enveloped (''Coronaviridae'', ''Fla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infectious Disease (medical Specialty)
Infectious diseases or ID, also known as infectiology, is a medical specialty dealing with the diagnosis and treatment of infections. An infectious diseases specialist's practice consists of managing nosocomial ( healthcare-acquired) infections or community-acquired infections and is historically associated with hygiene, epidemiology, clinical microbiology, travel medicine and tropical medicine. Scope Infectious diseases specialists typically serve as consultants to other physicians in cases of complex infections, and often manage patients with HIV/AIDS and other forms of immunodeficiency. Although many common infections are treated by physicians without formal expertise in infectious diseases, specialists may be consulted for cases where an infection is difficult to diagnose or manage. They may also be asked to help determine the cause of a fever of unknown origin. Specialists in infectious diseases can practice both in hospitals (inpatient) and clinics (outpatient). In ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiviral Drug
Antiviral drugs are a class of medication used for treating viral infections. Most antivirals target specific viruses, while a broad-spectrum antiviral is effective against a wide range of viruses. Unlike most antibiotics, antiviral drugs do not destroy their target pathogen; instead they inhibit its development. Antiviral drugs are one class of antimicrobials, a larger group which also includes antibiotic (also termed antibacterial), antifungal and antiparasitic drugs, or antiviral drugs based on monoclonal antibodies. Most antivirals are considered relatively harmless to the host, and therefore can be used to treat infections. They should be distinguished from viricides, which are not medication but deactivate or destroy virus particles, either inside or outside the body. Natural viricides are produced by some plants such as eucalyptus and Australian tea trees. Medical uses Most of the antiviral drugs now available are designed to help deal with HIV, herpes viruse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malaria
Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. Symptoms usually begin ten to fifteen days after being bitten by an infected mosquito. If not properly treated, people may have recurrences of the disease months later. In those who have recently survived an infection, reinfection usually causes milder symptoms. This partial resistance disappears over months to years if the person has no continuing exposure to malaria. Malaria is caused by single-celled microorganisms of the '' Plasmodium'' group. It is spread exclusively through bites of infected '' Anopheles'' mosquitoes. The mosquito bite introduces the parasites from the mosquito's saliva into a person's blood. The parasites travel to the liver where they mature and reproduce. Five species of ''Plasmodium'' can infect and be spr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Antiviral Drug")
