Alphavirus: A genus of TOGAVIRIDAE, also known as Group A arboviruses, serologically related to each other but not to other Togaviridae. The viruses are transmitted by mosquitoes. The type species is the SINDBIS VIRUS.Alphavirus Infections: Virus diseases caused by members of the ALPHAVIRUS genus of the family TOGAVIRIDAE.Sindbis Virus: The type species of ALPHAVIRUS normally transmitted to birds by CULEX mosquitoes in Egypt, South Africa, India, Malaya, the Philippines, and Australia. It may be associated with fever in humans. Serotypes (differing by less than 17% in nucleotide sequence) include Babanki, Kyzylagach, and Ockelbo viruses.Chikungunya virus: A species of ALPHAVIRUS causing an acute dengue-like fever.Semliki forest virus: A species of ALPHAVIRUS isolated in central, eastern, and southern Africa.Encephalitis Virus, Venezuelan Equine: A species of ALPHAVIRUS that is the etiologic agent of encephalomyelitis in humans and equines. It is seen most commonly in parts of Central and South America.Ross River virus: A species of ALPHAVIRUS associated with epidemic EXANTHEMA and polyarthritis in Australia.Encephalitis Virus, Western Equine: A species of ALPHAVIRUS that is the etiologic agent of encephalomyelitis in humans and equines in the United States, southern Canada, and parts of South America.Swallows: The family Hirundinidae, comprised of small BIRDS that hunt flying INSECTS while in sustained flight.Replicon: Any DNA sequence capable of independent replication or a molecule that possesses a REPLICATION ORIGIN and which is therefore potentially capable of being replicated in a suitable cell. (Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)Cimicidae: A family of wingless, blood-sucking insects of the suborder HETEROPTERA, including the bedbugs and related forms. Cimex (BEDBUGS), Heamatosiphon, and Oeciacus are medically important genera. (From Dorland, 28th ed)Encephalitis Virus, Eastern Equine: A species of ALPHAVIRUS causing encephalomyelitis in Equidae and humans. The virus ranges along the Atlantic seaboard of the United States and Canada and as far south as the Caribbean, Mexico, and parts of Central and South America. Infections in horses show a mortality of up to 90 percent and in humans as high as 80 percent in epidemics.Culicidae: A family of the order DIPTERA that comprises the mosquitoes. The larval stages are aquatic, and the adults can be recognized by the characteristic WINGS, ANIMAL venation, the scales along the wing veins, and the long proboscis. Many species are of particular medical importance.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Aedes: A genus of mosquitoes (CULICIDAE) frequently found in tropical and subtropical regions. YELLOW FEVER and DENGUE are two of the diseases that can be transmitted by species of this genus.Encephalomyelitis, Venezuelan Equine: A form of arboviral encephalitis endemic to Central America and the northern latitudes of South America. The causative organism (ENCEPHALITIS VIRUS, VENEZUELAN EQUINE) is transmitted to humans and horses via the bite of several mosquito species. Human viral infection may be asymptomatic or remain restricted to a mild influenza-like illness. Encephalitis, usually not severe, occurs in a small percentage of cases and may rarely feature SEIZURES and COMA. (From Joynt, Clinical Neurology, 1996, Ch26, pp9-10)Arboviruses: Arthropod-borne viruses. A non-taxonomic designation for viruses that can replicate in both vertebrate hosts and arthropod vectors. Included are some members of the following families: ARENAVIRIDAE; BUNYAVIRIDAE; REOVIRIDAE; TOGAVIRIDAE; and FLAVIVIRIDAE. (From Dictionary of Microbiology and Molecular Biology, 2nd ed)Togaviridae Infections: Virus diseases caused by the TOGAVIRIDAE.Salmo salar: A commercially important species of SALMON in the family SALMONIDAE, order SALMONIFORMES, which occurs in the North Atlantic.Arbovirus Infections: Infections caused by arthropod-borne viruses, general or unspecified.Virus Replication: The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Encephalomyelitis, Equine: A group of ALPHAVIRUS INFECTIONS which affect horses and man, transmitted via the bites of mosquitoes. Disorders in this category are endemic to regions of South America and North America. In humans, clinical manifestations vary with the type of infection, and range from a mild influenza-like syndrome to a fulminant encephalitis. (From Joynt, Clinical Neurology, 1996, Ch26, pp8-10)Viral Envelope Proteins: Layers of protein which surround the capsid in animal viruses with tubular nucleocapsids. The envelope consists of an inner layer of lipids and virus specified proteins also called membrane or matrix proteins. The outer layer consists of one or more types of morphological subunits called peplomers which project from the viral envelope; this layer always consists of glycoproteins.Togaviridae: A family of RNA viruses, mainly arboviruses, consisting of two genera: ALPHAVIRUS (group A arboviruses), and RUBIVIRUS. Virions are spherical, 60-70 nm in diameter, with a lipoprotein envelope tightly applied to the icosahedral nucleocapsid.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Fish Diseases: Diseases of freshwater, marine, hatchery or aquarium fish. This term includes diseases of both teleosts (true fish) and elasmobranchs (sharks, rays and skates).Sparrows: The family Passeridae comprised of small, mainly brown and grey seed-eating birds with conical bills.Virus Assembly: The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.Viral Vaccines: Suspensions of attenuated or killed viruses administered for the prevention or treatment of infectious viral disease.Viral Nonstructural Proteins: Proteins encoded by a VIRAL GENOME that are produced in the organisms they infect, but not packaged into the VIRUS PARTICLES. Some of these proteins may play roles within the infected cell during VIRUS REPLICATION or act in regulation of virus replication or VIRUS ASSEMBLY.Vero Cells: A CELL LINE derived from the kidney of the African green (vervet) monkey, (CERCOPITHECUS AETHIOPS) used primarily in virus replication studies and plaque assays.Virus Release: Release of a virus from the host cell following VIRUS ASSEMBLY and maturation. Egress can occur by host cell lysis, EXOCYTOSIS, or budding through the plasma membrane.Encephalitis, Viral: Inflammation of brain parenchymal tissue as a result of viral infection. Encephalitis may occur as primary or secondary manifestation of TOGAVIRIDAE INFECTIONS; HERPESVIRIDAE INFECTIONS; ADENOVIRIDAE INFECTIONS; FLAVIVIRIDAE INFECTIONS; BUNYAVIRIDAE INFECTIONS; PICORNAVIRIDAE INFECTIONS; PARAMYXOVIRIDAE INFECTIONS; ORTHOMYXOVIRIDAE INFECTIONS; RETROVIRIDAE INFECTIONS; and ARENAVIRIDAE INFECTIONS.Genetic Vectors: DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.Encephalomyelitis: A general term indicating inflammation of the BRAIN and SPINAL CORD, often used to indicate an infectious process, but also applicable to a variety of autoimmune and toxic-metabolic conditions. There is significant overlap regarding the usage of this term and ENCEPHALITIS in the literature.NebraskaAntibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Genome, Viral: The complete genetic complement contained in a DNA or RNA molecule in a virus.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Encephalomyelitis, Western Equine: A form of arboviral encephalitis (which primarily affects horses) endemic to western and central regions of NORTH AMERICA. The causative organism (ENCEPHALOMYELITIS VIRUS, WESTERN EQUINE) may be transferred to humans via the bite of mosquitoes (CULEX tarsalis and others). Clinical manifestations include headache and influenza-like symptoms followed by alterations in mentation, SEIZURES, and COMA. DEATH occurs in a minority of cases. Survivors may recover fully or be left with residual neurologic dysfunction, including PARKINSONISM, POSTENCEPHALITIC. (From Joynt, Clinical Neurology, 1996, Ch26, pp8-9)Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Flavivirus: A genus of FLAVIVIRIDAE containing several subgroups and many species. Most are arboviruses transmitted by mosquitoes or ticks. The type species is YELLOW FEVER VIRUS.Flavivirus Infections: Infections with viruses of the genus FLAVIVIRUS, family FLAVIVIRIDAE.Laboratories: Facilities equipped to carry out investigative procedures.Clinical Laboratory Techniques: Techniques used to carry out clinical investigative procedures in the diagnosis and therapy of disease.Public Health: Branch of medicine concerned with the prevention and control of disease and disability, and the promotion of physical and mental health of the population on the international, national, state, or municipal level.Dictionaries, MedicalDictionaries as Topic: Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.Insect Vectors: Insects that transmit infective organisms from one host to another or from an inanimate reservoir to an animate host.Culex: A genus of mosquitoes (CULICIDAE) commonly found in tropical regions. Species of this genus are vectors for ST. LOUIS ENCEPHALITIS as well as many other diseases of man and domestic and wild animals.