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.Smallpox: An acute, highly contagious, often fatal infectious disease caused by an orthopoxvirus characterized by a biphasic febrile course and distinctive progressive skin eruptions. Vaccination has succeeded in eradicating smallpox worldwide. (Dorland, 28th ed)Male Urogenital Diseases: Pathological processes of the male URINARY TRACT and the reproductive system (GENITALIA, MALE).Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Gonorrhea: Acute infectious disease characterized by primary invasion of the urogenital tract. The etiologic agent, NEISSERIA GONORRHOEAE, was isolated by Neisser in 1879.Female Urogenital Diseases: Pathological processes of the female URINARY TRACT and the reproductive system (GENITALIA, FEMALE).Chlamydia Infections: Infections with bacteria of the genus CHLAMYDIA.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).Air Travel: Aspects of health and disease related to air travel. It includes the physiologic and psychologic beneficial or adverse effects.Tuberculosis: Any of the infectious diseases of man and other animals caused by species of MYCOBACTERIUM.Cuba: An island in the Greater Antilles in the West Indies, south of Florida. With the adjacent islands it forms the Republic of Cuba. Its capital is Havana. It was discovered by Columbus on his first voyage in 1492 and conquered by Spain in 1511. It has a varied history under Spain, Great Britain, and the United States but has been independent since 1902. The name Cuba is said to be an Indian name of unknown origin but the language that gave the name is extinct, so the etymology is a conjecture. (From Webster's New Geographical Dictionary, 1988, p302 & Room, Brewer's Dictionary of Names, 1992, p132)Tuberculosis, Pulmonary: MYCOBACTERIUM infections of the lung.Tuberculin Test: One of several skin tests to determine past or present tuberculosis infection. A purified protein derivative of the tubercle bacilli, called tuberculin, is introduced into the skin by scratch, puncture, or interdermal injection.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)Sexually Transmitted Diseases: Diseases due to or propagated by sexual contact.Communicable DiseasesCommunicable Disease Control: Programs of surveillance designed to prevent the transmission of disease by any means from person to person or from animal to man.Mass Screening: Organized periodic procedures performed on large groups of people for the purpose of detecting disease.Mycobacterium tuberculosis: A species of gram-positive, aerobic bacteria that produces TUBERCULOSIS in humans, other primates, CATTLE; DOGS; and some other animals which have contact with humans. Growth tends to be in serpentine, cordlike masses in which the bacilli show a parallel orientation.Chlamydia trachomatis: Type species of CHLAMYDIA causing a variety of ocular and urogenital diseases.Sexual Partners: Married or single individuals who share sexual relations.WalesTravel: Aspects of health and disease related to travel.Disease Notification: Notification or reporting by a physician or other health care provider of the occurrence of specified contagious diseases such as tuberculosis and HIV infections to designated public health agencies. The United States system of reporting notifiable diseases evolved from the Quarantine Act of 1878, which authorized the US Public Health Service to collect morbidity data on cholera, smallpox, and yellow fever; each state in the US has its own list of notifiable diseases and depends largely on reporting by the individual health care provider. (From Segen, Dictionary of Modern Medicine, 1992)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.Syphilis: A contagious venereal disease caused by the spirochete TREPONEMA PALLIDUM.Contact Lenses: Lenses designed to be worn on the front surface of the eyeball. (UMDNS, 1999)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.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.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.Computer Simulation: Computer-based representation of physical systems and phenomena such as chemical processes.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.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.DNA Fingerprinting: A technique for identifying individuals of a species that is based on the uniqueness of their DNA sequence. Uniqueness is determined by identifying which combination of allelic variations occur in the individual at a statistically relevant number of different loci. In forensic studies, RESTRICTION FRAGMENT LENGTH POLYMORPHISM of multiple, highly polymorphic VNTR LOCI or MICROSATELLITE REPEAT loci are analyzed. The number of loci used for the profile depends on the ALLELE FREQUENCY in the population.Stochastic Processes: Processes that incorporate some element of randomness, used particularly to refer to a time series of random variables.Polymorphism, Restriction Fragment Length: Variation occurring within a species in the presence or length of DNA fragment generated by a specific endonuclease at a specific site in the genome. Such variations are generated by mutations that create or abolish recognition sites for these enzymes or change the length of the fragment.EnglandGreat BritainAntitubercular Agents: Drugs used in the treatment of tuberculosis. They are divided into two main classes: "first-line" agents, those with the greatest efficacy and acceptable degrees of toxicity used successfully in the great majority of cases; and "second-line" drugs used in drug-resistant cases or those in which some other patient-related condition has compromised the effectiveness of primary therapy.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.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.Dermatitis, Contact: A type of acute or chronic skin reaction in which sensitivity is manifested by reactivity to materials or substances coming in contact with the skin. It may involve allergic or non-allergic mechanisms.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.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.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.Referral and Consultation: The practice of sending a patient to another program or practitioner for services or advice which the referring source is not prepared to provide.Contact Lenses, Hydrophilic: Soft, supple contact lenses made of plastic polymers which interact readily with water molecules. Many types are available, including continuous and extended-wear versions, which are gas-permeable and easily sterilized.Dermatitis, Allergic Contact: A contact dermatitis due to allergic sensitization to various substances. These substances subsequently produce inflammatory reactions in the skin of those who have acquired hypersensitivity to them as a result of prior exposure.