Enterovirus: A genus of the family PICORNAVIRIDAE whose members preferentially inhabit the intestinal tract of a variety of hosts. The genus contains many species. Newly described members of human enteroviruses are assigned continuous numbers with the species designated "human enterovirus".Enterovirus InfectionsEnterovirus A, Human: A species of ENTEROVIRUS infecting humans and containing 10 serotypes, mostly coxsackieviruses.Enterovirus B, Human: A species of ENTEROVIRUS infecting humans and containing 36 serotypes. It is comprised of all the echoviruses and a few coxsackieviruses, including all of those previously named coxsackievirus B.Enteroviruses, Porcine: Species of ENTEROVIRUS causing mild to severe neurological diseases among pigs especially in Eastern Europe. Mild strains are also present in Canada, U.S., and Australia. Specific species include Porcine enterovirus A and Porcine enterovirus B.Hand, Foot and Mouth Disease: A mild, highly infectious viral disease of children, characterized by vesicular lesions in the mouth and on the hands and feet. It is caused by coxsackieviruses A.Enterovirus D, Human: A species of ENTEROVIRUS infecting humans and consisting of 2 serotypes: Human enterovirus 68 and Human enterovirus 70.Enterovirus, Bovine: A species in the family ENTEROVIRUS infecting cattle.Echovirus Infections: Infectious disease processes, including meningitis, diarrhea, and respiratory disorders, caused by echoviruses.Meningitis, Aseptic: A syndrome characterized by headache, neck stiffness, low grade fever, and CSF lymphocytic pleocytosis in the absence of an acute bacterial pathogen. Viral meningitis is the most frequent cause although MYCOPLASMA INFECTIONS; RICKETTSIA INFECTIONS; diagnostic or therapeutic procedures; NEOPLASTIC PROCESSES; septic perimeningeal foci; and other conditions may result in this syndrome. (From Adams et al., Principles of Neurology, 6th ed, p745)Poliovirus: A species of ENTEROVIRUS which is the causal agent of POLIOMYELITIS in humans. Three serotypes (strains) exist. Transmission is by the fecal-oral route, pharyngeal secretions, or mechanical vector (flies). Vaccines with both inactivated and live attenuated virus have proven effective in immunizing against the infection.HerpanginaMeningitis, Viral: Viral infections of the leptomeninges and subarachnoid space. TOGAVIRIDAE INFECTIONS; FLAVIVIRIDAE INFECTIONS; RUBELLA; BUNYAVIRIDAE INFECTIONS; ORBIVIRUS infections; PICORNAVIRIDAE INFECTIONS; ORTHOMYXOVIRIDAE INFECTIONS; RHABDOVIRIDAE INFECTIONS; ARENAVIRIDAE INFECTIONS; HERPESVIRIDAE INFECTIONS; ADENOVIRIDAE INFECTIONS; JC VIRUS infections; and RETROVIRIDAE INFECTIONS may cause this form of meningitis. Clinical manifestations include fever, headache, neck pain, vomiting, PHOTOPHOBIA, and signs of meningeal irritation. (From Joynt, Clinical Neurology, 1996, Ch26, pp1-3)Coxsackievirus Infections: A heterogeneous group of infections produced by coxsackieviruses, including HERPANGINA, aseptic meningitis (MENINGITIS, ASEPTIC), a common-cold-like syndrome, a non-paralytic poliomyelitis-like syndrome, epidemic pleurodynia (PLEURODYNIA, EPIDEMIC) and a serious MYOCARDITIS.Sewage: Refuse liquid or waste matter carried off by sewers.Virus Cultivation: Process of growing viruses in live animals, plants, or cultured cells.Echovirus 9: A species of ENTEROVIRUS associated with outbreaks of aseptic meningitis (MENINGITIS, ASEPTIC).RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Capsid Proteins: Proteins that form the CAPSID of VIRUSES.Rhinovirus: A genus of PICORNAVIRIDAE inhabiting primarily the respiratory tract of mammalian hosts. It includes over 100 human serotypes associated with the COMMON COLD.Picornaviridae: A family of small RNA viruses comprising some important pathogens of humans and animals. Transmission usually occurs mechanically. There are nine genera: APHTHOVIRUS; CARDIOVIRUS; ENTEROVIRUS; ERBOVIRUS; HEPATOVIRUS; KOBUVIRUS; PARECHOVIRUS; RHINOVIRUS; and TESCHOVIRUS.Picornaviridae Infections: Virus diseases caused by the PICORNAVIRIDAE.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Water Microbiology: The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.Echovirus 6, Human: A species of ENTEROVIRUS that has caused outbreaks of aseptic meningitis in children and adults.Virology: The study of the structure, growth, function, genetics, and reproduction of viruses, and VIRUS DISEASES.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.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.5' Untranslated Regions: The sequence at the 5' end of the messenger RNA that does not code for product. This sequence contains the ribosome binding site and other transcription and translation regulating sequences.Paralysis: A general term most often used to describe severe or complete loss of muscle strength due to motor system disease from the level of the cerebral cortex to the muscle fiber. This term may also occasionally refer to a loss of sensory function. (From Adams et al., Principles of Neurology, 6th ed, p45)Serotyping: Process of determining and distinguishing species of bacteria or viruses based on antigens they share.Genome, Viral: The complete genetic complement contained in a DNA or RNA molecule in a virus.Cerebrospinal Fluid: A watery fluid that is continuously produced in the CHOROID PLEXUS and circulates around the surface of the BRAIN; SPINAL CORD; and in the CEREBRAL VENTRICLES.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Water Pollution: Contamination of bodies of water (such as LAKES; RIVERS; SEAS; and GROUNDWATER.)Viruses: Minute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Poliomyelitis: An acute infectious disease of humans, particularly children, caused by any of three serotypes of human poliovirus (POLIOVIRUS). Usually the infection is limited to the gastrointestinal tract and nasopharynx, and is often asymptomatic. The central nervous system, primarily the spinal cord, may be affected, leading to rapidly progressive paralysis, coarse FASCICULATION and hyporeflexia. Motor neurons are primarily affected. Encephalitis may also occur. The virus replicates in the nervous system, and may cause significant neuronal loss, most notably in the spinal cord. A rare related condition, nonpoliovirus poliomyelitis, may result from infections with nonpoliovirus enteroviruses. (From Adams et al., Principles of Neurology, 6th ed, pp764-5)Parechovirus: A genus in the family PICORNAVIRIDAE infecting humans and rodents. The type species is Human parechovirus.Feces: Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Conjunctivitis, Acute Hemorrhagic: A highly contagious disease characterized by subconjunctival hemorrhage, sudden swelling of the eyelids and congestion, redness, and pain in the eye. Epidemic conjunctivitis caused by Enterovirus 70 (EV-70) was first described in Africa in 1969. It is caused also by Coxsackievirus A24 variant (CA24v). Epidemics by this organism have appeared most frequently in Asia.Reverse Transcriptase Polymerase Chain Reaction: A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.ConjunctivitisAntibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Neutralization Tests: The measurement of infection-blocking titer of ANTISERA by testing a series of dilutions for a given virus-antiserum interaction end-point, which is generally the dilution at which tissue cultures inoculated with the serum-virus mixtures demonstrate cytopathology (CPE) or the dilution at which 50% of test animals injected with serum-virus mixtures show infectivity (ID50) or die (LD50).Shellfish: Aquatic invertebrates belonging to the phylum MOLLUSCA or the subphylum CRUSTACEA, and used as food.Cytopathogenic Effect, Viral: Visible morphologic changes in cells infected with viruses. It includes shutdown of cellular RNA and protein synthesis, cell fusion, release of lysosomal enzymes, changes in cell membrane permeability, diffuse changes in intracellular structures, presence of viral inclusion bodies, and chromosomal aberrations. It excludes malignant transformation, which is CELL TRANSFORMATION, VIRAL. Viral cytopathogenic effects provide a valuable method for identifying and classifying the infecting viruses.Myocarditis: Inflammatory processes of the muscular walls of the heart (MYOCARDIUM) which result in injury to the cardiac muscle cells (MYOCYTES, CARDIAC). Manifestations range from subclinical to sudden death (DEATH, SUDDEN). Myocarditis in association with cardiac dysfunction is classified as inflammatory CARDIOMYOPATHY usually caused by INFECTION, autoimmune diseases, or responses to toxic substances. Myocarditis is also a common cause of DILATED CARDIOMYOPATHY and other cardiomyopathies.Central Nervous System Viral Diseases: Viral infections of the brain, spinal cord, meninges, or perimeningeal spaces.Filtration: A process of separating particulate matter from a fluid, such as air or a liquid, by passing the fluid carrier through a medium that will not pass the particulates. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Antigens, CD55: GPI-linked membrane proteins broadly distributed among hematopoietic and non-hematopoietic cells. CD55 prevents the assembly of C3 CONVERTASE or accelerates the disassembly of preformed convertase, thus blocking the formation of the membrane attack complex.Virus Diseases: A general term for diseases produced by viruses.Hepatitis A virus: A species in the genus HEPATOVIRUS containing one serotype and two strains: HUMAN HEPATITIS A VIRUS and Simian hepatitis A virus causing hepatitis in humans (HEPATITIS A) and primates, respectively.Capsid: The outer protein protective shell of a virus, which protects the viral nucleic acid.Cercopithecus aethiops: A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.Viral Proteins: Proteins found in any species of virus.Viral Structural Proteins: Viral proteins that are components of the mature assembled VIRUS PARTICLES. They may include nucleocapsid core proteins (gag proteins), enzymes packaged within the virus particle (pol proteins), and membrane components (env proteins). These do not include the proteins encoded in the VIRAL GENOME that are produced in infected cells but which are not packaged in the mature virus particle,i.e. the so called non-structural proteins (VIRAL NONSTRUCTURAL PROTEINS).Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Molecular Epidemiology: The application of molecular biology to the answering of epidemiological questions. The examination of patterns of changes in DNA to implicate particular carcinogens and the use of molecular markers to predict which individuals are at highest risk for a disease are common examples.Viral Plaque Assay: Method for measuring viral infectivity and multiplication in CULTURED CELLS. Clear lysed areas or plaques develop as the VIRAL PARTICLES are released from the infected cells during incubation. With some VIRUSES, the cells are killed by a cytopathic effect; with others, the infected cells are not killed but can be detected by their hemadsorptive ability. Sometimes the plaque cells contain VIRAL ANTIGENS which can be measured by IMMUNOFLUORESCENCE.Ion Exchange Resins: High molecular weight, insoluble polymers which contain functional groups that are capable of undergoing exchange reactions (ION EXCHANGE) with either cations or anions.Waste Disposal, Fluid: The discarding or destroying of liquid waste products or their transformation into something useful or innocuous.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)