Travel: Aspects of health and disease related to travel.Travel Medicine: Multidisciplinary field focusing on prevention of infectious diseases and patient safety during international TRAVEL. Key element of patient's pre-travel visit to the physician is a health risk assessment.Aircraft: A weight-carrying structure for navigation of the air that is supported either by its own buoyancy or by the dynamic action of the air against its surfaces. (Webster, 1973)Transportation: The means of moving persons, animals, goods, or materials from one place to another.Aerospace Medicine: That branch of medicine dealing with the studies and effects of flight through the atmosphere or in space upon the human body and with the prevention or cure of physiological or psychological malfunctions arising from these effects. (from NASA Thesaurus)Air Travel: Aspects of health and disease related to air travel. It includes the physiologic and psychologic beneficial or adverse effects.Jet Lag Syndrome: A chronobiologic disorder resulting from rapid travel across a number of time zones, characterized by insomnia or hypersomnolence, fatigue, behavioral symptoms, headaches, and gastrointestinal disturbances. (From Cooper, Sleep, 1994, pp593-8)Medical Tourism: Travel to another country for the purpose of medical treatment.Bicycling: The use of a bicycle for transportation or recreation. It does not include the use of a bicycle in studying the body's response to physical exertion (BICYCLE ERGOMETRY TEST see EXERCISE TEST).Geographic Information Systems: Computer systems capable of assembling, storing, manipulating, and displaying geographically referenced information, i.e. data identified according to their locations.Tropical Medicine: The branch of medicine concerned with diseases, mainly of parasitic origin, common in tropical and subtropical regions.United States Department of Homeland Security: A cabinet department in the Executive Branch of the United States Government concerned with administering those agencies and offices having programs pertaining to domestic national security.Walking: An activity in which the body advances at a slow to moderate pace by moving the feet in a coordinated fashion. This includes recreational walking, walking for fitness, and competitive race-walking.Communicable DiseasesHealth Services Accessibility: The degree to which individuals are inhibited or facilitated in their ability to gain entry to and to receive care and services from the health care system. Factors influencing this ability include geographic, architectural, transportational, and financial considerations, among others.Transportation of Patients: Conveying ill or injured individuals from one place to another.Aviation: Design, development, manufacture, and operation of heavier-than-air AIRCRAFT.Motor Vehicles: AUTOMOBILES, trucks, buses, or similar engine-driven conveyances. (From Random House Unabridged Dictionary, 2d ed)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.Automobiles: A usually four-wheeled automotive vehicle designed for passenger transportation and commonly propelled by an internal-combustion engine using a volatile fuel. (Webster, 1973)Catchment Area (Health): A geographic area defined and served by a health program or institution.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.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.United StatesSpace Flight: Travel beyond the earth's atmosphere.Airports: Terminal facilities used for aircraft takeoff and landing and including facilities for handling passengers. (from McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed.)Automobile Driving: The effect of environmental or physiological factors on the driver and driving ability. Included are driving fatigue, and the effect of drugs, disease, and physical disabilities on driving.Internationality: The quality or state of relating to or affecting two or more nations. (After Merriam-Webster Collegiate Dictionary, 10th ed)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)Environment Design: The structuring of the environment to permit or promote specific patterns of behavior.Centralized Hospital Services: The coordination of services in one area of a facility to improve efficiency.Communicable Diseases, Emerging: Infectious diseases that are novel in their outbreak ranges (geographic and host) or transmission mode.Parasitic Diseases: Infections or infestations with parasitic organisms. They are often contracted through contact with an intermediate vector, but may occur as the result of direct exposure.Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.Holidays: Days commemorating events. Holidays also include vacation periods.Weightlessness: Condition in which no acceleration, whether due to gravity or any other force, can be detected by an observer within a system. It also means the absence of weight or the absence of the force of gravity acting on a body. Microgravity, gravitational force between 0 and 10 -6 g, is included here. (From NASA Thesaurus, 1988)Accidents, Traffic: Accidents on streets, roads, and highways involving drivers, passengers, pedestrians, or vehicles. Traffic accidents refer to AUTOMOBILES (passenger cars, buses, and trucks), BICYCLING, and MOTORCYCLES but not OFF-ROAD MOTOR VEHICLES; RAILROADS nor snowmobiles.Health Facility Planning: Areawide planning for health care institutions on the basis of projected consumer need.Rural Health Services: Health services, public or private, in rural areas. The services include the promotion of health and the delivery of health care.Schools: Educational institutions.Rural Population: The inhabitants of rural areas or of small towns classified as rural.Emigration and Immigration: The process of leaving one's country to establish residence in a foreign country.Homing Behavior: Instinctual patterns of activity related to a specific area including ability of certain animals to return to a given place when displaced from it, often over great distances using navigational clues such as those used in migration (ANIMAL MIGRATION).