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Viral Encephalitis
Viral encephalitis is inflammation of the brain parenchyma, called encephalitis, by a virus. The different forms of viral encephalitis are called viral encephalitides. It is the most common type of encephalitis and often occurs with viral meningitis. Encephalitic viruses first cause infection and replicate outside of the central nervous system (CNS), most reaching the CNS through the circulatory system and a minority from nerve endings toward the CNS. Once in the brain, the virus and the host's inflammatory response disrupt neural function, leading to illness and complications, many of which frequently are neurological in nature, such as impaired motor skills and altered behavior. Viral encephalitis can be diagnosed based on the individual's symptoms, personal history, such as travel history, and different clinical tests such as histology, medical imaging, and lumbar punctures. A differential diagnosis can also be done to rule out other causes of the encephalitis. Many encephalitic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflammation
Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or 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 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 immunity, as compared to adaptive immunity, which is specific for each pathogen. Too little inflammation could lead to progressive tissue destruction by the harmful stimulus (e.g. bacteria) and compromise the survival of the organism. In contrast, too much inflammation, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dengue Virus
''Dengue virus'' (DENV) is the cause of dengue fever. It is a mosquito-borne, single positive-stranded RNA virus of the family '' Flaviviridae''; genus '' Flavivirus''. Four serotypes of the virus have been found, a reported fifth has yet to be confirmed,Dwivedi, V. D., Tripathi, I. P., Tripathi, R. C., Bharadwaj, S., & Mishra, S. K. (2017). Genomics, proteomics and evolution of ''Dengue virus''. Briefings in functional genomics.16(4): 217–227, https://doi.org/10.1093/bfgp/elw040 all of which can cause the full spectrum of disease. Nevertheless, scientists' understanding of dengue virus may be simplistic as, rather than distinct antigenic groups, a ''continuum'' appears to exist. This same study identified 47 strains of ''dengue virus''. Additionally, coinfection with and lack of rapid tests for ''zika virus'' and ''chikungunya'' complicate matters in real-world infections. ''Dengue virus'' has increased dramatically within the last 20 years, becoming one of the worst mosq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Measles Virus
''Measles morbillivirus'' (MeV), also called measles virus (MV), is a single-stranded, negative-sense, enveloped, non-segmented RNA virus of the genus '' Morbillivirus'' within the family '' Paramyxoviridae''. It is the cause of measles. Humans are the natural hosts of the virus; no animal reservoirs are known to exist. Disease The virus causes measles, a highly contagious disease transmitted by respiratory aerosols that triggers a temporary but severe immunosuppression. Symptoms include fever, cough, runny nose, inflamed eyes and a generalized, maculopapular, erythematous rash and a pathognomic Koplik spot seen on buccal mucosa opposite to lower 1 st and 2 nd molars . The virus is spread by coughing and sneezing via close personal contact or direct contact with secretions. Replication cycle Entry The measles virus has two envelope glycoproteins on the viral surface – hemagglutinin (H) and membrane fusion protein (F). These proteins are responsible for host ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lymphocytic Choriomeningitis Mammarenavirus
Lymphocytic choriomeningitis (LCM) is a rodent-borne viral infectious disease that presents as aseptic meningitis, encephalitis or meningoencephalitis. Its causative agent is ''lymphocytic choriomeningitis mammarenavirus'' (LCMV), a member of the family '' Arenaviridae''. The name was coined by Charles Armstrong in 1934. Lymphocytic choriomeningitis (LCM) is "a viral infection of the membranes surrounding the brain and spinal cord and of the cerebrospinal fluid". Lasker, Jill S. "Lymphocytic choriomeningitis". The name is based on the tendency of an individual to have abnormally high levels of lymphocytes during infection. Choriomeningitis is "cerebral meningitis in which there is marked cellular infiltration of the meninges, often with a lymphocytic infiltration of the choroid plexuses". Signs and symptoms LCMV infection manifests itself in a wide range of clinical symptoms, and may even be asymptomatic for immunocompetent individuals. CDC. "Information for Pet Owners: Red ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Crosse Virus
La Crosse encephalitis is an encephalitis caused by an arbovirus (the La Crosse virus) which has a mosquito vector ('' Ochlerotatus triseriatus'' synonym ''Aedes'' ''triseriatus''). La Crosse encephalitis virus (LACV) is one of a group of mosquito-transmitted viruses that can cause encephalitis, or inflammation of the brain. LAC encephalitis is rare; in the United States, about 80–100 LACV disease cases are reported each year, although it is believed to be under-reported due to minimal symptoms experienced by many of those affected. Signs and symptoms It takes 5 to 15 days after the bite of an infected mosquito to develop symptoms of LACV disease. Symptoms include nausea, headache, vomiting in milder cases and seizures, coma, paralysis and permanent brain damage in severe cases. LAC encephalitis initially presents as a nonspecific summertime illness with fever, headache, nausea, vomiting and lethargy. Severe disease occurs most commonly in children under the age of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Japanese Encephalitis Virus
Japanese encephalitis (JE) is an infection of the brain caused by the Japanese encephalitis virus (JEV). While most infections result in little or no symptoms, occasional inflammation of the brain occurs. In these cases, symptoms may include headache, vomiting, fever, confusion and seizures. This occurs about 5 to 15 days after infection. JEV is generally spread by mosquitoes, specifically those of the ''Culex'' type. Pigs and wild birds serve as a reservoir for the virus. The disease occurs mostly outside of cities. Diagnosis is based on blood or cerebrospinal fluid testing. Prevention is generally with the Japanese encephalitis vaccine, which is both safe and effective. Other measures include avoiding mosquito bites. Once infected, there is no specific treatment, with care being supportive. This is generally carried out in a hospital. Permanent problems occur in up to half of people who recover from JE. The disease primarily occurs in East and Southeast Asia as well as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jamestown Canyon Virus
Jamestown Canyon encephalitis is an infectious disease caused by the Jamestown Canyon virus, an orthobunyavirus of the California serogroup. It is mainly spread during the summer by different mosquito species in the United States and Canada. The virus is one of a group of mosquito-borne or arthropod-borne viruses, also called arboviruses, that can cause fever and meningitis or meningoencephalitis, mostly in adults. Jamestown Canyon virus disease is relatively rare; in the United States, the CDC found only 31 disease cases from 2000 to 2013, but it is likely under-recognized and probably endemic throughout most of the United States and parts of Canada. Signs and symptoms About 2 days to 2 weeks after the bite of an infected mosquito, disease symptoms of a nonspecific summertime illness with sore throat, runny nose and cough, followed by fever, headache, nausea and vomiting can develop. Many cases are asymptomatic, although the ratio of symptomatic to asymptomatic cases is unkn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Influenza Virus
''Orthomyxoviridae'' (from Greek ὀρθός, ''orthós'' 'straight' + μύξα, ''mýxa'' 'mucus') is a family of negative-sense RNA viruses. It includes seven genera: ''Alphainfluenzavirus'', ''Betainfluenzavirus'', '' Gammainfluenzavirus'', '' Deltainfluenzavirus'', ''Isavirus'', ''Thogotovirus'', and ''Quaranjavirus''. The first four genera contain viruses that cause influenza in birds (see also avian influenza) and mammals, including humans. Isaviruses infect salmon; the thogotoviruses are arboviruses, infecting vertebrates and invertebrates (such as ticks and mosquitoes). The Quaranjaviruses are also arboviruses, infecting vertebrates (birds) and invertebrates (arthropods). The four genera of Influenza virus that infect vertebrates, which are identified by antigenic differences in their nucleoprotein and matrix protein, are as follows: * ''Alphainfluenzavirus'' infects humans, other mammals, and birds, and causes all flu pandemics * ''Betainfluenzavirus'' infects huma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Herpesvirus 7
''Human betaherpesvirus 7'' (HHV-7) is one of nine known members of the ''Herpesviridae'' family that infects humans. HHV-7 is a member of ''Betaherpesvirinae'', a subfamily of the ''Herpesviridae'' that also includes HHV-6 and '' Cytomegalovirus'' (HHV-5 or HCMV). HHV-7 often acts together with HHV-6, and the viruses together are sometimes referred to by their genus, ''Roseolovirus''. HHV-7 was first isolated in 1990 from CD4+ T cells taken from peripheral blood lymphocytes. Signs and symptoms Both HHV-6B and HHV-7, as well as other viruses, can cause a skin condition in infants known as exanthema subitum, although HHV-7 causes the disease less frequently than HHV-6B. HHV-7 infection also leads to or is associated with a number of other symptoms, including acute febrile respiratory disease, fever, rash, vomiting, diarrhea, low lymphocyte counts, and febrile seizures, though most often no symptoms present at all. There are indications that HHV-7 can contribute to the develop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Herpesvirus 6
Human herpesvirus 6 (HHV-6) is the common collective name for '' human betaherpesvirus 6A'' (HHV-6A) and '' human betaherpesvirus 6B'' (HHV-6B). These closely related viruses are two of the nine known herpesviruses that have humans as their primary host. HHV-6A and HHV-6B are double-stranded DNA viruses within the ''Betaherpesvirinae'' subfamily and of the genus ''Roseolovirus''. HHV-6A and HHV-6B infect almost all of the human populations that have been tested. HHV-6A has been described as more neurovirulent, and as such is more frequently found in patients with neuroinflammatory diseases such as multiple sclerosis. HHV-6 (and HHV-7) levels in the brain are also elevated in people with Alzheimer's disease. HHV-6B primary infection is the cause of the common childhood illness exanthema subitum (also known as roseola infantum or sixth disease). It is passed on from child to child. It is uncommon for adults to contract this disease as most people have had it by kindergarten, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herpes Simplex Virus
Herpes simplex virus 1 and 2 (HSV-1 and HSV-2), also known by their taxonomical names '' Human alphaherpesvirus 1'' and ''Human alphaherpesvirus 2'', are two members of the human ''Herpesviridae'' family, a set of viruses that produce viral infections in the majority of humans. Both HSV-1 and HSV-2 are very common and contagious. They can be spread when an infected person begins shedding the virus. As of 2016, about 67% of the world population under the age of 50 had HSV-1. In the United States, about 47.8% and 11.9% are estimated to have HSV-1 and HSV-2, respectively, though actual prevalence may be much higher. Because it can be transmitted through any intimate contact, it is one of the most common sexually transmitted infections. Symptoms Many of those who are infected ''never'' develop symptoms. Symptoms, when they occur, may include watery blisters in the skin or mucous membranes of the mouth, lips, nose, genitals, or eyes ( herpes simplex keratitis). Lesions heal w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
