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Polio
Poliomyelitis ( ), commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 75% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe symptoms develop such as headache, neck stiffness, and paresthesia. These symptoms usually pass within one or two weeks. A less common symptom is permanent Flaccid paralysis, paralysis, and possible death in extreme cases.. Years after recovery, post-polio syndrome may occur, with a slow development of muscle weakness similar to what the person had during the initial infection. Polio occurs naturally only in humans. It is highly infectious, and is spread from person to person either through fecal–oral route, fecal–oral transmission (e.g. poor hygiene, or by ingestion of food or water contaminated by human feces), or via the oral–oral route. Those who are infected may spread the disease for up to six weeks even if no symptoms are pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polio Vaccine
Polio vaccines are vaccines used to prevent poliomyelitis (polio). Two types are used: an inactivated vaccine, inactivated poliovirus given by injection (IPV) and a attenuated vaccine, weakened poliovirus given by mouth (OPV). The World Health Organization (WHO) recommends all children be fully vaccinated against polio. The two vaccines have eliminated polio from most of the world, and reduced the number of cases reported each year from an estimated 350,000 in 1988 to 33 in 2018. The inactivated polio vaccines are very safe. Mild redness or pain may occur at the site of injection. Oral polio vaccines cause about three cases of vaccine-associated paralytic poliomyelitis per million doses given. This compares with 5,000 cases per million who are paralysed following a polio infection. Both types of vaccine are generally safe to give during pregnancy and in those who have HIV/AIDS, but are otherwise well. However, the emergence of circulating vaccine-derived poliovirus (cVDPV), a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poliovirus
Poliovirus, the causative agent of polio (also known as poliomyelitis), is a serotype of the species '' Enterovirus C'', in the family of '' Picornaviridae''. There are three poliovirus serotypes, numbered 1, 2, and 3. Poliovirus is composed of an RNA genome and a protein capsid. The genome is a single-stranded positive-sense RNA (+ssRNA) genome that is about 7500 nucleotides long. The viral particle is about 30 nm in diameter with icosahedral symmetry. Because of its short genome and its simple composition—only a strand of RNA and a nonenveloped icosahedral protein coat encapsulating it—poliovirus is widely regarded as the simplest significant virus. Poliovirus is one of the most well-characterized viruses, and has become a useful model system for understanding the biology of RNA viruses. Replication cycle Poliovirus infects human cells by binding to an immunoglobulin-like receptor, CD155 (also known as the poliovirus receptor or PVR) on the cell surface. Inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Post-polio Syndrome
Post-polio syndrome (PPS, poliomyelitis sequelae) is a group of latent symptoms of poliomyelitis (polio), occurring in more than 80% of polio infections. The symptoms are caused by the damaging effects of the viral infection on the nervous system and typically occur 15 to 30 years after an initial acute paralytic attack. Symptoms include decreasing muscular function or acute weakness with pain and fatigue. The same may also occur years after a nonparalytic polio infection. The precise mechanism that causes PPS is unknown. It shares many features with chronic fatigue syndrome, but unlike that disorder it tends to be progressive and can cause loss of muscle strength. Treatment is primarily limited to adequate rest, conservation of available energy, and supportive measures, such as leg braces and energy-saving devices such as powered wheelchairs, analgesia (pain relief), and sleep aids. Signs and symptoms After a period of prolonged stability, some people who recover from pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flaccid Paralysis
Flaccid paralysis is a neurological condition characterized by weakness or paralysis and reduced muscle tone without other obvious cause (e.g., trauma). This abnormal condition may be caused by disease or by trauma affecting the nerves associated with the involved muscles. For example, if the somatic nerves to a skeletal muscle are severed, then the muscle will exhibit flaccid paralysis. When muscles enter this state, they become limp and cannot contract. This condition can become fatal if it affects the respiratory muscles, posing the threat of suffocation. It also occurs in the spinal shock stage in complete transection of the spinal cord occurring in injuries such as gunshot wounds.Saladin, Kenneth S. Anatomy & Physiology: The Unity of Form and Function. McGraw-Hill. 6th Edition. 2012. Causes Polio and other viruses The term ''acute flaccid paralysis'' (AFP) is often used to describe an instance with a sudden onset, as might be found with polio. AFP is the most co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attenuated Vaccine
An attenuated vaccine (or a live attenuated vaccine, LAV) is a vaccine created by reducing the virulence of a pathogen, but still keeping it viable (or "live"). Attenuation takes an infectious agent and alters it so that it becomes harmless or less virulent. These vaccines contrast to those produced by "killing" the pathogen ( inactivated vaccine). Attenuated vaccines stimulate a strong and effective immune response that is long-lasting. In comparison to inactivated vaccines, attenuated vaccines produce a stronger and more durable immune response with a quick immunity onset. They are generally avoided in pregnancy and in patients with severe immunodeficiencies. Attenuated vaccines function by encouraging the body to create antibodies and memory immune cells in response to the specific pathogen which the vaccine protects against. Common examples of live attenuated vaccines are measles, mumps, rubella, yellow fever, varicella, and some influenza vaccines. Development Attenua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flaccid Paralysis
Flaccid paralysis is a neurological condition characterized by weakness or paralysis and reduced muscle tone without other obvious cause (e.g., trauma). This abnormal condition may be caused by disease or by trauma affecting the nerves associated with the involved muscles. For example, if the somatic nerves to a skeletal muscle are severed, then the muscle will exhibit flaccid paralysis. When muscles enter this state, they become limp and cannot contract. This condition can become fatal if it affects the respiratory muscles, posing the threat of suffocation. It also occurs in the spinal shock stage in complete transection of the spinal cord occurring in injuries such as gunshot wounds.Saladin, Kenneth S. Anatomy & Physiology: The Unity of Form and Function. McGraw-Hill. 6th Edition. 2012. Causes Polio and other viruses The term ''acute flaccid paralysis'' (AFP) is often used to describe an instance with a sudden onset, as might be found with polio. AFP is the most co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inactivated Vaccine
An inactivated vaccine (or killed vaccine) is a type of vaccine that contains pathogens (such as virus or bacteria) that have been killed or rendered inactive, so they cannot replicate or cause disease. In contrast, live vaccines use pathogens that are still alive (but are almost always attenuated, that is, weakened). Pathogens for inactivated vaccines are grown under controlled conditions and are killed as a means to reduce infectivity and thus prevent infection from the vaccine. Inactivated vaccines were first developed in the late 1800s and early 1900s for cholera, plague, and typhoid. In 1897, Japanese scientists developed an inactivated vaccine for the bubonic plague. In the 1950s, Jonas Salk created an inactivated vaccine for the poliovirus, creating the first vaccine that was both safe and effective against polio. Today, inactivated vaccines exist for many pathogens, including influenza, polio (IPV), rabies, hepatitis A, CoronaVac, Covaxin and pertussis. Because ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Landsteiner
Karl Landsteiner (; 14 June 1868 – 26 June 1943) was an Austrian-American biologist, physician, and immunologist. He emigrated with his family to New York in 1923 at the age of 55 for professional opportunities, working for the Rockefeller Institute. He had distinguished the main blood groups in 1901, having developed the modern system of classification of blood groups from his identification of the presence of agglutinins in the blood. In 1937, with Alexander S. Wiener, he identified the Rhesus factor, thus enabling physicians to transfuse blood without endangering the patient's life. With Constantin Levaditi and Erwin Popper, he discovered the polio virus in 1909. He received the Aronson Prize in 1926. In 1930, he received the Nobel Prize in Physiology or Medicine. He was posthumously awarded the Lasker Award in 1946, and has been described as the father of transfusion medicine. Early life and education He was born into a Jewish family. His father Leopold Landste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fecal–oral Route
The fecal–oral route (also called the oral–fecal route or orofecal route) describes a particular route of transmission of a disease wherein pathogens in fecal particles pass from one person to the mouth of another person. Main causes of fecal–oral disease transmission include lack of adequate sanitation (leading to open defecation), and poor hygiene practices. If soil or water bodies are polluted with fecal material, humans can be infected with waterborne diseases or soil-transmitted diseases. Fecal contamination of food is another form of fecal-oral transmission. Washing hands properly after changing a baby's diaper or after performing anal hygiene can prevent foodborne illness from spreading..Toilet flushing & subsequent inhaled aerosols is another potential route. The common factors in the fecal-oral route can be summarized as five Fs: fingers, flies, fields, fluids, and food. Diseases caused by fecal-oral transmission include typhoid, cholera, polio, hepat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
