Disease Transmission, Infectious: The transmission of infectious disease or pathogens. When transmission is within the same species, the mode can be horizontal or vertical (INFECTIOUS DISEASE TRANSMISSION, VERTICAL).Germ Theory of Disease: The fundamental tenet of modern medicine that certain diseases are caused by microorganisms. It was confirmed by the work of Pasteur, Lister, and Koch.Communicable DiseasesInfectious Disease Transmission, Patient-to-Professional: The transmission of infectious disease or pathogens from patients to health professionals or health care workers. It includes transmission via direct or indirect exposure to bacterial, fungal, parasitic, or viral agents.Infectious Disease Transmission, Professional-to-Patient: The transmission of infectious disease or pathogens from health professional or health care worker to patients. It includes transmission via direct or indirect exposure to bacterial, fungal, parasitic, or viral agents.Infectious Disease Transmission, Vertical: The transmission of infectious disease or pathogens from one generation to another. It includes transmission in utero or intrapartum by exposure to blood and secretions, and postpartum exposure via breastfeeding.Communicable Disease Control: Programs of surveillance designed to prevent the transmission of disease by any means from person to person or from animal to man.Insect Vectors: Insects that transmit infective organisms from one host to another or from an inanimate reservoir to an animate host.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Disease Vectors: Invertebrates or non-human vertebrates which transmit infective organisms from one host to another.Insect Control: The reduction or regulation of the population of noxious, destructive, or dangerous insects through chemical, biological, or other means.Infectious Disease Medicine: A branch of internal medicine concerned with the diagnosis and treatment of INFECTIOUS DISEASES.Communicable Diseases, Emerging: Infectious diseases that are novel in their outbreak ranges (geographic and host) or transmission mode.Synaptic Transmission: The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.Contact Tracing: Identification of those persons (or animals) who have had such an association with an infected person, animal, or contaminated environment as to have had the opportunity to acquire the infection. Contact tracing is a generally accepted method for the control of sexually transmitted diseases.Zoonoses: Diseases of non-human animals that may be transmitted to HUMANS or may be transmitted from humans to non-human animals.Triatominae: A subfamily of assassin bugs (REDUVIIDAE) that are obligate blood-suckers of vertebrates. Included are the genera TRIATOMA; RHODNIUS; and PANSTRONGYLUS, which are vectors of TRYPANOSOMA CRUZI, the agent of CHAGAS DISEASE in humans.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.Chagas Disease: Infection with the protozoan parasite TRYPANOSOMA CRUZI, a form of TRYPANOSOMIASIS endemic in Central and South America. It is named after the Brazilian physician Carlos Chagas, who discovered the parasite. Infection by the parasite (positive serologic result only) is distinguished from the clinical manifestations that develop years later, such as destruction of PARASYMPATHETIC GANGLIA; CHAGAS CARDIOMYOPATHY; and dysfunction of the ESOPHAGUS or COLON.Animals, Wild: Animals considered to be wild or feral or not adapted for domestic use. It does not include wild animals in zoos for which ANIMALS, ZOO is available.Models, Theoretical: Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.Arthropod Vectors: Arthropods, other than insects and arachnids, which transmit infective organisms from one host to another or from an inanimate reservoir to an animate host.Epidemics: Sudden outbreaks of a disease in a country or region not previously recognized in that area, or a rapid increase in the number of new cases of a previous existing endemic disease. Epidemics can also refer to outbreaks of disease in animal or plant populations.Insect Bites and Stings: Bites and stings inflicted by insects.Geographic Information Systems: Computer systems capable of assembling, storing, manipulating, and displaying geographically referenced information, i.e. data identified according to their locations.Seasons: Divisions of the year according to some regularly recurrent phenomena usually astronomical or climatic. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Triatoma: A genus of the subfamily TRIATOMINAE. Several species are vectors of TRYPANOSOMA CRUZI.Topography, Medical: The systematic surveying, mapping, charting, and description of specific geographical sites, with reference to the physical features that were presumed to influence health and disease. Medical topography should be differentiated from EPIDEMIOLOGY in that the former emphasizes geography whereas the latter emphasizes disease outbreaks.National Institute of Allergy and Infectious Diseases (U.S.): Component of the NATIONAL INSTITUTES OF HEALTH. It conducts and supports basic and applied research to better understand, treat, and ultimately prevent infectious, immunologic, and allergic diseases. It was established in 1948.Travel: Aspects of health and disease related to travel.Malaria: A protozoan disease caused in humans by four species of the PLASMODIUM genus: PLASMODIUM FALCIPARUM; PLASMODIUM VIVAX; PLASMODIUM OVALE; and PLASMODIUM MALARIAE; and transmitted by the bite of an infected female mosquito of the genus ANOPHELES. Malaria is endemic in parts of Asia, Africa, Central and South America, Oceania, and certain Caribbean islands. It is characterized by extreme exhaustion associated with paroxysms of high FEVER; SWEATING; shaking CHILLS; and ANEMIA. Malaria in ANIMALS is caused by other species of plasmodia.Population Dynamics: The pattern of any process, or the interrelationship of phenomena, which affects growth or change within a population.Geographic Mapping: Creating a representation of areas of the earth or other celestial bodies, for the purpose of visualizing spatial distributions of various information.Primate Diseases: Diseases of animals within the order PRIMATES. This term includes diseases of Haplorhini and Strepsirhini.Population Surveillance: Ongoing scrutiny of a population (general population, study population, target population, etc.), generally using methods distinguished by their practicability, uniformity, and frequently their rapidity, rather than by complete accuracy.Animals, Domestic: Animals which have become adapted through breeding in captivity to a life intimately associated with humans. They include animals domesticated by humans to live and breed in a tame condition on farms or ranches for economic reasons, including LIVESTOCK (specifically CATTLE; SHEEP; HORSES; etc.), POULTRY; and those raised or kept for pleasure and companionship, e.g., PETS; or specifically DOGS; CATS; etc.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Infection: Invasion of the host organism by microorganisms that can cause pathological conditions or diseases.Parasitic Diseases, Animal: Infections or infestations with parasitic organisms. The infestation may be experimental or veterinary.Influenza, Human: An acute viral infection in humans involving the respiratory tract. It is marked by inflammation of the NASAL MUCOSA; the PHARYNX; and conjunctiva, and by headache and severe, often generalized, myalgia.Anopheles: A genus of mosquitoes (CULICIDAE) that are known vectors of MALARIA.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.Disease Reservoirs: Animate or inanimate sources which normally harbor disease-causing organisms and thus serve as potential sources of disease outbreaks. Reservoirs are distinguished from vectors (DISEASE VECTORS) and carriers, which are agents of disease transmission rather than continuing sources of potential disease outbreaks.Endemic Diseases: The constant presence of diseases or infectious agents within a given geographic area or population group. It may also refer to the usual prevalence of a given disease with such area or group. It includes holoendemic and hyperendemic diseases. A holoendemic disease is one for which a high prevalent level of infection begins early in life and affects most of the child population, leading to a state of equilibrium such that the adult population shows evidence of the disease much less commonly than do children (malaria in many communities is a holoendemic disease). A hyperendemic disease is one that is constantly present at a high incidence and/or prevalence rate and affects all groups equally. (Last, A Dictionary of Epidemiology, 3d ed, p53, 78, 80)Mustelidae: A family of terrestrial carnivores with long, slender bodies, long tails, and anal scent glands. They include badgers, weasels, martens, FERRETS; MINKS; wolverines, polecats, and OTTERS.Infection Control: Programs of disease surveillance, generally within health care facilities, designed to investigate, prevent, and control the spread of infections and their causative microorganisms.Rhodnius: A genus of the subfamily TRIATOMINAE. Rhodnius prolixus is a vector for TRYPANOSOMA CRUZI.Microscopy, Electron, Transmission: Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.HIV Infections: Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, thru AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).Trypanosoma cruzi: The agent of South American trypanosomiasis or CHAGAS DISEASE. Its vertebrate hosts are man and various domestic and wild animals. Insects of several species are vectors.Population Density: Number of individuals in a population relative to space.Rain: Water particles that fall from the ATMOSPHERE.Schistosomiasis: Infection with flukes (trematodes) of the genus SCHISTOSOMA. Three species produce the most frequent clinical diseases: SCHISTOSOMA HAEMATOBIUM (endemic in Africa and the Middle East), SCHISTOSOMA MANSONI (in Egypt, northern and southern Africa, some West Indies islands, northern 2/3 of South America), and SCHISTOSOMA JAPONICUM (in Japan, China, the Philippines, Celebes, Thailand, Laos). S. mansoni is often seen in Puerto Ricans living in the United States.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.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.Host-Parasite Interactions: The relationship between an invertebrate and another organism (the host), one of which lives at the expense of the other. Traditionally excluded from definition of parasites are pathogenic BACTERIA; FUNGI; VIRUSES; and PLANTS; though they may live parasitically.Prion Diseases: A group of genetic, infectious, or sporadic degenerative human and animal nervous system disorders associated with abnormal PRIONS. These diseases are characterized by conversion of the normal prion protein to an abnormal configuration via a post-translational process. In humans, these conditions generally feature DEMENTIA; ATAXIA; and a fatal outcome. Pathologic features include a spongiform encephalopathy without evidence of inflammation. The older literature occasionally refers to these as unconventional SLOW VIRUS DISEASES. (From Proc Natl Acad Sci USA 1998 Nov 10;95(23):13363-83)Ecosystem: A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)Computer Simulation: Computer-based representation of physical systems and phenomena such as chemical processes.EcuadorOrgan Transplantation: Transference of an organ between individuals of the same species or between individuals of different species.Geography: The science dealing with the earth and its life, especially the description of land, sea, and air and the distribution of plant and animal life, including humanity and human industries with reference to the mutual relations of these elements. (From Webster, 3d ed)Models, Statistical: Statistical formulations or analyses which, when applied to data and found to fit the data, are then used to verify the assumptions and parameters used in the analysis. Examples of statistical models are the linear model, binomial model, polynomial model, two-parameter model, etc.Time Factors: Elements of limited time intervals, contributing to particular results or situations.VenezuelaHygiene: The science dealing with the establishment and maintenance of health in the individual and the group. It includes the conditions and practices conducive to health. (Webster, 3d ed)Anopheles gambiae: A species of mosquito in the genus Anopheles and the principle vector of MALARIA in Africa.Housing: Living facilities for humans.Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.Foot-and-Mouth DiseaseMass Vaccination: Administration of a vaccine to large populations in order to elicit IMMUNITY.Mosquito Control: The reduction or regulation of the population of mosquitoes through chemical, biological, or other means.Deer: The family Cervidae of 17 genera and 45 species occurring nearly throughout North America, South America, and Eurasia, on most associated continental islands, and in northern Africa. Wild populations of deer have been established through introduction by people in Cuba, New Guinea, Australia, New Zealand, and other places where the family does not naturally occur. They are slim, long-legged and best characterized by the presence of antlers. Their habitat is forests, swamps, brush country, deserts, and arctic tundra. They are usually good swimmers; some migrate seasonally. (Walker's Mammals of the World, 5th ed, p1362)Air Microbiology: The presence of bacteria, viruses, and fungi in the air. This term is not restricted to pathogenic organisms.PeruAnimal Husbandry: The science of breeding, feeding and care of domestic animals; includes housing and nutrition.Environment: The external elements and conditions which surround, influence, and affect the life and development of an organism or population.Seroepidemiologic Studies: EPIDEMIOLOGIC STUDIES based on the detection through serological testing of characteristic change in the serum level of specific ANTIBODIES. Latent subclinical infections and carrier states can thus be detected in addition to clinically overt cases.Stochastic Processes: Processes that incorporate some element of randomness, used particularly to refer to a time series of random variables.Prions: Small proteinaceous infectious particles which resist inactivation by procedures that modify NUCLEIC ACIDS and contain an abnormal isoform of a cellular protein which is a major and necessary component. The abnormal (scrapie) isoform is PrPSc (PRPSC PROTEINS) and the cellular isoform PrPC (PRPC PROTEINS). The primary amino acid sequence of the two isoforms is identical. Human diseases caused by prions include CREUTZFELDT-JAKOB SYNDROME; GERSTMANN-STRAUSSLER SYNDROME; and INSOMNIA, FATAL FAMILIAL.Wasting Disease, Chronic: A transmissible spongiform encephalopathy (prion disease) of DEER and elk characterized by chronic weight loss leading to death. It is thought to spread by direct contact between animals or through environmental contamination with the prion protein (PRIONS).Infant, Newborn: An infant during the first month after birth.Water Supply: Means or process of supplying water (as for a community) usually including reservoirs, tunnels, and pipelines and often the watershed from which the water is ultimately drawn. (Webster, 3d ed)Phlebotomus: A genus of PSYCHODIDAE which functions as the vector of a number of pathogenic organisms, including LEISHMANIA DONOVANI; LEISHMANIA TROPICA; Bartonella bacilliformis, and the Pappataci fever virus (SANDFLY FEVER NAPLES VIRUS).Vaccination: Administration of vaccines to stimulate the host's immune response. This includes any preparation intended for active immunological prophylaxis.Climate: The longterm manifestations of WEATHER. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)United StatesDengue: An acute febrile disease transmitted by the bite of AEDES mosquitoes infected with DENGUE VIRUS. It is self-limiting and characterized by fever, myalgia, headache, and rash. SEVERE DENGUE is a more virulent form of dengue.Cluster Analysis: A set of statistical methods used to group variables or observations into strongly inter-related subgroups. In epidemiology, it may be used to analyze a closely grouped series of events or cases of disease or other health-related phenomenon with well-defined distribution patterns in relation to time or place or both.Sterilization: The destroying of all forms of life, especially microorganisms, by heat, chemical, or other means.Social Behavior: Any behavior caused by or affecting another individual, usually of the same species.Animal DiseasesCulex: 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.Water Microbiology: The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.Incidence: The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases, new or old, in the population at a given time.Ticks: Blood-sucking acarid parasites of the order Ixodida comprising two families: the softbacked ticks (ARGASIDAE) and hardbacked ticks (IXODIDAE). Ticks are larger than their relatives, the MITES. They penetrate the skin of their host by means of highly specialized, hooked mouth parts and feed on its blood. Ticks attack all groups of terrestrial vertebrates. In humans they are responsible for many TICK-BORNE DISEASES, including the transmission of ROCKY MOUNTAIN SPOTTED FEVER; TULAREMIA; BABESIOSIS; AFRICAN SWINE FEVER; and RELAPSING FEVER. (From Barnes, Invertebrate Zoology, 5th ed, pp543-44)Equipment Contamination: The presence of an infectious agent on instruments, prostheses, or other inanimate articles.BrazilRural Population: The inhabitants of rural areas or of small towns classified as rural.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Ecology: The branch of science concerned with the interrelationship of organisms and their ENVIRONMENT, especially as manifested by natural cycles and rhythms, community development and structure, interactions between different kinds of organisms, geographic distributions, and population alterations. (Webster's, 3d ed)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.Thailand: Formerly known as Siam, this is a Southeast Asian nation at the center of the Indochina peninsula. Bangkok is the capital city.Larva: Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.Insecticides: Pesticides designed to control insects that are harmful to man. The insects may be directly harmful, as those acting as disease vectors, or indirectly harmful, as destroyers of crops, food products, or textile fabrics.Bacterial Infections: Infections by bacteria, general or unspecified.Virus Diseases: A general term for diseases produced by viruses.Cryptosporidiosis: Intestinal infection with organisms of the genus CRYPTOSPORIDIUM. It occurs in both animals and humans. Symptoms include severe DIARRHEA.Cross Infection: Any infection which a patient contracts in a health-care institution.Genotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.Feeding Behavior: Behavioral responses or sequences associated with eating including modes of feeding, rhythmic patterns of eating, and time intervals.Influenza A Virus, H1N1 Subtype: A subtype of INFLUENZA A VIRUS with the surface proteins hemagglutinin 1 and neuraminidase 1. The H1N1 subtype was responsible for the Spanish flu pandemic of 1918.Pandemics: Epidemics of infectious disease that have spread to many countries, often more than one continent, and usually affecting a large number of people.Tissue Donors: Individuals supplying living tissue, organs, cells, blood or blood components for transfer or transplantation to histocompatible recipients.China: A country spanning from central Asia to the Pacific Ocean.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.Risk Assessment: The qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences. (Last, Dictionary of Epidemiology, 1988)Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Epidemiologic Methods: Research techniques that focus on study designs and data gathering methods in human and animal populations.