Methicillin-Resistant Staphylococcus aureus: A strain of Staphylococcus aureus that is non-susceptible to the action of METHICILLIN. The mechanism of resistance usually involves modification of normal or the presence of acquired PENICILLIN BINDING PROTEINS.Staphylococcus aureus: Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.Staphylococcal Infections: Infections with bacteria of the genus STAPHYLOCOCCUS.Methicillin Resistance: Non-susceptibility of a microbe to the action of METHICILLIN, a semi-synthetic penicillin derivative.Methicillin: One of the PENICILLINS which is resistant to PENICILLINASE but susceptible to a penicillin-binding protein. It is inactivated by gastric acid so administered by injection.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).Vancomycin: Antibacterial obtained from Streptomyces orientalis. It is a glycopeptide related to RISTOCETIN that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Staphylococcus: A genus of gram-positive, facultatively anaerobic, coccoid bacteria. Its organisms occur singly, in pairs, and in tetrads and characteristically divide in more than one plane to form irregular clusters. Natural populations of Staphylococcus are found on the skin and mucous membranes of warm-blooded animals. Some species are opportunistic pathogens of humans and animals.Staphylococcal Skin Infections: Infections to the skin caused by bacteria of the genus STAPHYLOCOCCUS.Community-Acquired Infections: Any infection acquired in the community, that is, contrasted with those acquired in a health care facility (CROSS INFECTION). An infection would be classified as community-acquired if the patient had not recently been in a health care facility or been in contact with someone who had been recently in a health care facility.Cross Infection: Any infection which a patient contracts in a health-care institution.Leukocidins: Pore forming proteins originally discovered for toxic activity to LEUKOCYTES. They are EXOTOXINS produced by some pathogenic STAPHYLOCOCCUS and STREPTOCOCCUS that destroy leukocytes by lysis of the cytoplasmic granules and are partially responsible for the pathogenicity of the organisms.Carrier State: The condition of harboring an infective organism without manifesting symptoms of infection. The organism must be readily transmissible to another susceptible host.Nose: A part of the upper respiratory tract. It contains the organ of SMELL. The term includes the external nose, the nasal cavity, and the PARANASAL SINUSES.Electrophoresis, Gel, Pulsed-Field: Gel electrophoresis in which the direction of the electric field is changed periodically. This technique is similar to other electrophoretic methods normally used to separate double-stranded DNA molecules ranging in size up to tens of thousands of base-pairs. However, by alternating the electric field direction one is able to separate DNA molecules up to several million base-pairs in length.Exotoxins: Toxins produced, especially by bacterial or fungal cells, and released into the culture medium or environment.Pneumonia, Staphylococcal: Pneumonia caused by infections with bacteria of the genus STAPHYLOCOCCUS, usually with STAPHYLOCOCCUS AUREUS.Oxazolidinones: Derivatives of oxazolidin-2-one. They represent an important class of synthetic antibiotic agents.Acetamides: Derivatives of acetamide that are used as solvents, as mild irritants, and in organic synthesis.Daptomycin: A cyclic lipopeptide antibiotic that inhibits GRAM-POSITIVE BACTERIA.Staphylococcal Protein A: A protein present in the cell wall of most Staphylococcus aureus strains. The protein selectively binds to the Fc region of human normal and myeloma-derived IMMUNOGLOBULIN G. It elicits antibody activity and may cause hypersensitivity reactions due to histamine release; has also been used as cell surface antigen marker and in the clinical assessment of B lymphocyte function.Oxacillin: An antibiotic similar to FLUCLOXACILLIN used in resistant staphylococci infections.Bacteremia: The presence of viable bacteria circulating in the blood. Fever, chills, tachycardia, and tachypnea are common acute manifestations of bacteremia. The majority of cases are seen in already hospitalized patients, most of whom have underlying diseases or procedures which render their bloodstreams susceptible to invasion.Staphylococcus epidermidis: A species of STAPHYLOCOCCUS that is a spherical, non-motile, gram-positive, chemoorganotrophic, facultative anaerobe. Mainly found on the skin and mucous membrane of warm-blooded animals, it can be primary pathogen or secondary invader.Vancomycin Resistance: Nonsusceptibility of bacteria to the action of VANCOMYCIN, an inhibitor of cell wall synthesis.Bacterial Typing Techniques: Procedures for identifying types and strains of bacteria. The most frequently employed typing systems are BACTERIOPHAGE TYPING and SEROTYPING as well as bacteriocin typing and biotyping.Soft Tissue Infections: Infections of non-skeletal tissue, i.e., exclusive of bone, ligaments, cartilage, and fibrous tissue. The concept is usually referred to as skin and soft tissue infections and usually subcutaneous and muscle tissue are involved. The predisposing factors in anaerobic infections are trauma, ischemia, and surgery. The organisms often derive from the fecal or oral flora, particularly in wounds associated with intestinal surgery, decubitus ulcer, and human bites. (From Cecil Textbook of Medicine, 19th ed, p1688)Mupirocin: A topically used antibiotic from a strain of Pseudomonas fluorescens. It has shown excellent activity against gram-positive staphylococci and streptococci. The antibiotic is used primarily for the treatment of primary and secondary skin disorders, nasal infections, and wound healing.Coagulase: Enzymes that cause coagulation in plasma by forming a complex with human PROTHROMBIN. Coagulases are produced by certain STAPHYLOCOCCUS and YERSINIA PESTIS. Staphylococci produce two types of coagulase: Staphylocoagulase, a free coagulase that produces true clotting of plasma, and Staphylococcal clumping factor, a bound coagulase in the cell wall that induces clumping of cells in the presence of fibrinogen.Bacterial Proteins: Proteins found in any species of bacterium.Staphylococcus Phages: Viruses whose host is Staphylococcus.Nasal Cavity: The proximal portion of the respiratory passages on either side of the NASAL SEPTUM. Nasal cavities, extending from the nares to the NASOPHARYNX, are lined with ciliated NASAL MUCOSA.Molecular Typing: Using MOLECULAR BIOLOGY techniques, such as DNA SEQUENCE ANALYSIS; PULSED-FIELD GEL ELECTROPHORESIS; and DNA FINGERPRINTING, to identify, classify, and compare organisms and their subtypes.Penicillin Resistance: Nonsusceptibility of an organism to the action of penicillins.Bacterial Toxins: Toxic substances formed in or elaborated by bacteria; they are usually proteins with high molecular weight and antigenicity; some are used as antibiotics and some to skin test for the presence of or susceptibility to certain diseases.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Drug Resistance, Bacterial: The ability of bacteria to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).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.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.Penicillin-Binding Proteins: Bacterial proteins that share the property of binding irreversibly to PENICILLINS and other ANTIBACTERIAL AGENTS derived from LACTAMS. The penicillin-binding proteins are primarily enzymes involved in CELL WALL biosynthesis including MURAMOYLPENTAPEPTIDE CARBOXYPEPTIDASE; PEPTIDE SYNTHASES; TRANSPEPTIDASES; and HEXOSYLTRANSFERASES.Fusidic Acid: An antibiotic isolated from the fermentation broth of Fusidium coccineum. (From Merck Index, 11th ed). It acts by inhibiting translocation during protein synthesis.Anti-Infective Agents: Substances that prevent infectious agents or organisms from spreading or kill infectious agents in order to prevent the spread of infection.Livestock: Domesticated farm animals raised for home use or profit but excluding POULTRY. Typically livestock includes CATTLE; SHEEP; HORSES; SWINE; GOATS; and others.Teicoplanin: Glycopeptide antibiotic complex from Actinoplanes teichomyceticus active against gram-positive bacteria. It consists of five major components each with a different fatty acid moiety.Bacteriophage Typing: A technique of bacterial typing which differentiates between bacteria or strains of bacteria by their susceptibility to one or more bacteriophages.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.Gram-Positive Bacteria: Bacteria which retain the crystal violet stain when treated by Gram's method.Endocarditis, Bacterial: Inflammation of the ENDOCARDIUM caused by BACTERIA that entered the bloodstream. The strains of bacteria vary with predisposing factors, such as CONGENITAL HEART DEFECTS; HEART VALVE DISEASES; HEART VALVE PROSTHESIS IMPLANTATION; or intravenous drug use.Drug Resistance, Multiple, Bacterial: The ability of bacteria to resist or to become tolerant to several structurally and functionally distinct drugs simultaneously. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Enterococcus: A genus of gram-positive, coccoid bacteria consisting of organisms causing variable hemolysis that are normal flora of the intestinal tract. Previously thought to be a member of the genus STREPTOCOCCUS, it is now recognized as a separate genus.Colony Count, Microbial: Enumeration by direct count of viable, isolated bacterial, archaeal, or fungal CELLS or SPORES capable of growth on solid CULTURE MEDIA. The method is used routinely by environmental microbiologists for quantifying organisms in AIR; FOOD; and WATER; by clinicians for measuring patients' microbial load; and in antimicrobial drug testing.OsteomyelitisPatient Isolation: The segregation of patients with communicable or other diseases for a specified time. Isolation may be strict, in which movement and social contacts are limited; modified, where an effort to control specified aspects of care is made in order to prevent cross infection; or reverse, where the patient is secluded in a controlled or germ-free environment in order to protect him or her from cross infection.Dibekacin: Analog of KANAMYCIN with antitubercular as well as broad-spectrum antimicrobial properties.Muramoylpentapeptide Carboxypeptidase: Enzyme which catalyzes the peptide cross-linking of nascent CELL WALL; PEPTIDOGLYCAN.Virulence Factors: Those components of an organism that determine its capacity to cause disease but are not required for its viability per se. Two classes have been characterized: TOXINS, BIOLOGICAL and surface adhesion molecules that effect the ability of the microorganism to invade and colonize a host. (From Davis et al., Microbiology, 4th ed. p486)Hospitals: Institutions with an organized medical staff which provide medical care to patients.Hexosyltransferases: Enzymes that catalyze the transfer of hexose groups. EC 2.4.1.-.Peptidyl Transferases: Acyltransferases that use AMINO ACYL TRNA as the amino acid donor in formation of a peptide bond. There are ribosomal and non-ribosomal peptidyltransferases.Lysostaphin: A 25-kDa peptidase produced by Staphylococcus simulans which cleaves a glycine-glcyine bond unique to an inter-peptide cross-bridge of the STAPHYLOCOCCUS AUREUS cell wall. EC 3.4.24.75.Hospitals, AnimalGenotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.Bacteriological Techniques: Techniques used in studying bacteria.Cephalosporins: A group of broad-spectrum antibiotics first isolated from the Mediterranean fungus ACREMONIUM. They contain the beta-lactam moiety thia-azabicyclo-octenecarboxylic acid also called 7-aminocephalosporanic acid.Abscess: Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.Clindamycin: An antibacterial agent that is a semisynthetic analog of LINCOMYCIN.Nasal Mucosa: The mucous lining of the NASAL CAVITY, including lining of the nostril (vestibule) and the OLFACTORY MUCOSA. Nasal mucosa consists of ciliated cells, GOBLET CELLS, brush cells, small granule cells, basal cells (STEM CELLS) and glands containing both mucous and serous cells.Drug Resistance, Microbial: The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Chromogenic Compounds: Colorless, endogenous or exogenous pigment precursors that may be transformed by biological mechanisms into colored compounds; used in biochemical assays and in diagnosis as indicators, especially in the form of enzyme substrates. Synonym: chromogens (not to be confused with pigment-synthesizing bacteria also called chromogens).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.Gram-Positive Bacterial Infections: Infections caused by bacteria that retain the crystal violet stain (positive) when treated by the gram-staining method.Gentamicins: A complex of closely related aminoglycosides obtained from MICROMONOSPORA purpurea and related species. They are broad-spectrum antibiotics, but may cause ear and kidney damage. They act to inhibit PROTEIN BIOSYNTHESIS.Multilocus Sequence Typing: Direct nucleotide sequencing of gene fragments from multiple housekeeping genes for the purpose of phylogenetic analysis, organism identification, and typing of species, strain, serovar, or other distinguishable phylogenetic level.Groin: The external junctural region between the lower part of the abdomen and the thigh.Microbial Viability: Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.Skin Diseases, Bacterial: Skin diseases caused by bacteria.Culture Media: Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.Wound Infection: Invasion of the site of trauma by pathogenic microorganisms.Anti-Infective Agents, Local: Substances used on humans and other animals that destroy harmful microorganisms or inhibit their activity. They are distinguished from DISINFECTANTS, which are used on inanimate objects.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Penicillins: A group of antibiotics that contain 6-aminopenicillanic acid with a side chain attached to the 6-amino group. The penicillin nucleus is the chief structural requirement for biological activity. The side-chain structure determines many of the antibacterial and pharmacological characteristics. (Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1065)Genes, Bacterial: The functional hereditary units of BACTERIA.Minocycline: A TETRACYCLINE analog, having a 7-dimethylamino and lacking the 5 methyl and hydroxyl groups, which is effective against tetracycline-resistant STAPHYLOCOCCUS infections.Veterinarians: Individuals with a degree in veterinary medicine that provides them with training and qualifications to treat diseases and injuries of animals.Nafcillin: A semi-synthetic antibiotic related to penicillin.Aminoglycosides: Glycosylated compounds in which there is an amino substituent on the glycoside. Some of them are clinically important ANTIBIOTICS.Surgical Wound Infection: Infection occurring at the site of a surgical incision.Gram-Negative Bacteria: Bacteria which lose crystal violet stain but are stained pink when treated by Gram's method.Ciprofloxacin: A broad-spectrum antimicrobial carboxyfluoroquinoline.beta-Lactams: Four-membered cyclic AMIDES, best known for the PENICILLINS based on a bicyclo-thiazolidine, as well as the CEPHALOSPORINS based on a bicyclo-thiazine, and including monocyclic MONOBACTAMS. The BETA-LACTAMASES hydrolyze the beta lactam ring, accounting for BETA-LACTAM RESISTANCE of infective bacteria.Rifampin: A semisynthetic antibiotic produced from Streptomyces mediterranei. It has a broad antibacterial spectrum, including activity against several forms of Mycobacterium. In susceptible organisms it inhibits DNA-dependent RNA polymerase activity by forming a stable complex with the enzyme. It thus suppresses the initiation of RNA synthesis. Rifampin is bactericidal, and acts on both intracellular and extracellular organisms. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p1160)Biofilms: Encrustations, formed from microbes (bacteria, algae, fungi, plankton, or protozoa) embedding in extracellular polymers, that adhere to surfaces such as teeth (DENTAL DEPOSITS); PROSTHESES AND IMPLANTS; and catheters. Biofilms are prevented from forming by treating surfaces with DENTIFRICES; DISINFECTANTS; ANTI-INFECTIVE AGENTS; and antifouling agents.Chromosomes, Bacterial: Structures within the nucleus of bacterial cells consisting of or containing DNA, which carry genetic information essential to the cell.Staphylococcus haemolyticus: A species of STAPHYLOCOCCUS found on the skin of humans (and non-human primates), often causing hospital-acquired infections (CROSS INFECTION).Patients' Rooms: Rooms occupied by one or more individuals during a stay in a health facility. The concept includes aspects of environment, design, care, or economics.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.Hospitals, University: Hospitals maintained by a university for the teaching of medical students, postgraduate training programs, and clinical research.Trimethoprim-Sulfamethoxazole Combination: This drug combination has proved to be an effective therapeutic agent with broad-spectrum antibacterial activity against both gram-positive and gram-negative organisms. It is effective in the treatment of many infections, including PNEUMOCYSTIS PNEUMONIA in AIDS.Glycopeptides: Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.Bacterial Infections: Infections by bacteria, general or unspecified.Prosthesis-Related Infections: Infections resulting from the implantation of prosthetic devices. The infections may be acquired from intraoperative contamination (early) or hematogenously acquired from other sites (late).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.Cloxacillin: A semi-synthetic antibiotic that is a chlorinated derivative of OXACILLIN.Equipment Contamination: The presence of an infectious agent on instruments, prostheses, or other inanimate articles.Fluoroquinolones: A group of QUINOLONES with at least one fluorine atom and a piperazinyl group.Skin Diseases, Infectious: Skin diseases caused by bacteria, fungi, parasites, or viruses.Intensive Care Units: Hospital units providing continuous surveillance and care to acutely ill patients.Bacteria: One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.PeptidoglycanCell Wall: The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.Virginiamycin: A cyclic polypeptide antibiotic complex from Streptomyces virginiae, S. loidensis, S. mitakaensis, S. pristina-spiralis, S. ostreogriseus, and others. It consists of 2 major components, VIRGINIAMYCIN FACTOR M1 and virginiamycin Factor S1. It is used to treat infections with gram-positive organisms and as a growth promoter in cattle, swine, and poultry.Staphylococcal VaccinesSequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Chlorhexidine: A disinfectant and topical anti-infective agent used also as mouthwash to prevent oral plaque.Virulence: The degree of pathogenicity within a group or species of microorganisms or viruses as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenic capacity of an organism is determined by its VIRULENCE FACTORS.Cefoxitin: A semisynthetic cephamycin antibiotic resistant to beta-lactamase.Interspersed Repetitive Sequences: Copies of transposable elements interspersed throughout the genome, some of which are still active and often referred to as "jumping genes". There are two classes of interspersed repetitive elements. Class I elements (or RETROELEMENTS - such as retrotransposons, retroviruses, LONG INTERSPERSED NUCLEOTIDE ELEMENTS and SHORT INTERSPERSED NUCLEOTIDE ELEMENTS) transpose via reverse transcription of an RNA intermediate. Class II elements (or DNA TRANSPOSABLE ELEMENTS - such as transposons, Tn elements, insertion sequence elements and mobile gene cassettes of bacterial integrons) transpose directly from one site in the DNA to another.Fosfomycin: An antibiotic produced by Streptomyces fradiae.Lincosamides: A family of LINCOMYCIN-related glycosides that contain a pyrrolidine ring linked via an amide-bond to a pyranose moiety. Individual members of this family are defined by the arrangement of specific constituent groups on the lyncomycin molecule. Many lincosamides are ANTIBIOTICS produced by a variety STREPTOMYCES species.Exfoliatins: Protein exotoxins from Staphylococcus aureus, phage type II, which cause epidermal necrolysis. They are proteins with a molecular weight of 26,000 to 32,000. They cause a condition variously called scaled skin, Lyell or Ritter syndrome, epidermal exfoliative disease, toxic epidermal necrolysis, etc.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.Imipenem: Semisynthetic thienamycin that has a wide spectrum of antibacterial activity against gram-negative and gram-positive aerobic and anaerobic bacteria, including many multiresistant strains. It is stable to beta-lactamases. Clinical studies have demonstrated high efficacy in the treatment of infections of various body systems. Its effectiveness is enhanced when it is administered in combination with CILASTATIN, a renal dipeptidase inhibitor.Zoonoses: Diseases of non-human animals that may be transmitted to HUMANS or may be transmitted from humans to non-human animals.Pristinamycin: An antibiotic mixture originally isolated from Streptomyces pristinaspiralis. It is a mixture of compounds from STREPTOGRAMIN GROUP A: pristinamycin IIA and IIB and from STREPTOGRAMIN GROUP B: pristinamycin IA, pristinamycin IB, pristinamycin IC.Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Agar: A complex sulfated polymer of galactose units, extracted from Gelidium cartilagineum, Gracilaria confervoides, and related red algae. It is used as a gel in the preparation of solid culture media for microorganisms, as a bulk laxative, in making emulsions, and as a supporting medium for immunodiffusion and immunoelectrophoresis.Enterotoxins: Substances that are toxic to the intestinal tract causing vomiting, diarrhea, etc.; most common enterotoxins are produced by bacteria.Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.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.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Bacteriolysis: Rupture of bacterial cells due to mechanical force, chemical action, or the lytic growth of BACTERIOPHAGES.Superantigens: Microbial antigens that have in common an extremely potent activating effect on T-cells that bear a specific variable region. Superantigens cross-link the variable region with class II MHC proteins regardless of the peptide binding in the T-cell receptor's pocket. The result is a transient expansion and subsequent death and anergy of the T-cells with the appropriate variable regions.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)Drug Synergism: The action of a drug in promoting or enhancing the effectiveness of another drug.Fomites: Inanimate objects that carry pathogenic microorganisms and thus can serve as the source of infection. Microorganisms typically survive on fomites for minutes or hours. Common fomites include CLOTHING, tissue paper, hairbrushes, and COOKING AND EATING UTENSILS.Hemolysin Proteins: Proteins from BACTERIA and FUNGI that are soluble enough to be secreted to target ERYTHROCYTES and insert into the membrane to form beta-barrel pores. Biosynthesis may be regulated by HEMOLYSIN FACTORS.Lactams: Cyclic AMIDES formed from aminocarboxylic acids by the elimination of water. Lactims are the enol forms of lactams.Gram-Positive Cocci: Coccus-shaped bacteria that retain the crystal violet stain when treated by Gram's method.Penicillinase: A beta-lactamase preferentially cleaving penicillins. (Dorland, 28th ed) EC 3.5.2.-.Communicable Diseases, Emerging: Infectious diseases that are novel in their outbreak ranges (geographic and host) or transmission mode.Cefazolin: A semisynthetic cephalosporin analog with broad-spectrum antibiotic action due to inhibition of bacterial cell wall synthesis. It attains high serum levels and is excreted quickly via the urine.Blood: The body fluid that circulates in the vascular system (BLOOD VESSELS). Whole blood includes PLASMA and BLOOD CELLS.TaiwanPseudomonas aeruginosa: A species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. aeruginosa is a major agent of nosocomial infection.Staphylococcus hominis: A species of STAPHYLOCOCCUS similar to STAPHYLOCOCCUS HAEMOLYTICUS, but containing different esterases. The subspecies Staphylococcus hominis novobiosepticus is highly virulent and novobiocin resistant.Drug Therapy, Combination: Therapy with two or more separate preparations given for a combined effect.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Carbapenems: A group of beta-lactam antibiotics in which the sulfur atom in the thiazolidine ring of the penicillin molecule is replaced by a carbon atom. THIENAMYCINS are a subgroup of carbapenems which have a sulfur atom as the first constituent of the side chain.Bacterial Load: Measurable quantity of bacteria in an object, organism, or organism compartment.Hand Disinfection: The act of cleansing the hands with water or other liquid, with or without the inclusion of soap or other detergent, for the purpose of destroying infectious microorganisms.Trimethoprim: A pyrimidine inhibitor of dihydrofolate reductase, it is an antibacterial related to PYRIMETHAMINE. It is potentiated by SULFONAMIDES and the TRIMETHOPRIM, SULFAMETHOXAZOLE DRUG COMBINATION is the form most often used. It is sometimes used alone as an antimalarial. TRIMETHOPRIM RESISTANCE has been reported.Cefamandole: Semisynthetic wide-spectrum cephalosporin with prolonged action, probably due to beta-lactamase resistance. It is used also as the nafate.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.NaphthyridinesRabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Environmental Microbiology: The study of microorganisms living in a variety of environments (air, soil, water, etc.) and their pathogenic relationship to other organisms including man.Disinfectants: Substances used on inanimate objects that destroy harmful microorganisms or inhibit their activity. Disinfectants are classed as complete, destroying SPORES as well as vegetative forms of microorganisms, or incomplete, destroying only vegetative forms of the organisms. They are distinguished from ANTISEPTICS, which are local anti-infective agents used on humans and other animals. (From Hawley's Condensed Chemical Dictionary, 11th ed)Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.Ofloxacin: A synthetic fluoroquinolone antibacterial agent that inhibits the supercoiling activity of bacterial DNA GYRASE, halting DNA REPLICATION.Sepsis: Systemic inflammatory response syndrome with a proven or suspected infectious etiology. When sepsis is associated with organ dysfunction distant from the site of infection, it is called severe sepsis. When sepsis is accompanied by HYPOTENSION despite adequate fluid infusion, it is called SEPTIC SHOCK.Drug Resistance, Multiple: Simultaneous resistance to several structurally and functionally distinct drugs.Antibiotic Prophylaxis: Use of antibiotics before, during, or after a diagnostic, therapeutic, or surgical procedure to prevent infectious complications.Streptogramin A: A specific streptogramin group A antibiotic produced by Streptomyces graminofaciens and other bacteria.Serum Bactericidal Test: Method of measuring the bactericidal activity contained in a patient's serum as a result of antimicrobial therapy. It is used to monitor the therapy in BACTERIAL ENDOCARDITIS; OSTEOMYELITIS and other serious bacterial infections. As commonly performed, the test is a variation of the broth dilution test. This test needs to be distinguished from testing of the naturally occurring BLOOD BACTERICIDAL ACTIVITY.Leptospermum: A plant genus of the family MYRTACEAE. The common name of tea tree is also used for MELALEUCA and KUNZEA.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Tetracycline: A naphthacene antibiotic that inhibits AMINO ACYL TRNA binding during protein synthesis.Animal Technicians: Assistants to a veterinarian, biological or biomedical researcher, or other scientist who are engaged in the care and management of animals, and who are trained in basic principles of animal life processes and routine laboratory and animal health care procedures. (Facts on File Dictionary of Health Care Management, 1988)Intensive Care Units, Neonatal: Hospital units providing continuing surveillance and care to acutely ill newborn infants.BelgiumPerineum: The body region lying between the genital area and the ANUS on the surface of the trunk, and to the shallow compartment lying deep to this area that is inferior to the PELVIC DIAPHRAGM. The surface area is between the VULVA and the anus in the female, and between the SCROTUM and the anus in the male.Nurseries, Hospital: Hospital facilities which provide care for newborn infants.Hospitals, Teaching: Hospitals engaged in educational and research programs, as well as providing medical care to the patients.Mastitis, Bovine: INFLAMMATION of the UDDER in cows.Lemierre Syndrome: A superinfection of the damaged oropharyngeal mucosa by FUSOBACTERIUM NECROPHORUM leading to the secondary septic THROMBOPHLEBITIS of the internal jugular vein.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Impetigo: A common superficial bacterial infection caused by STAPHYLOCOCCUS AUREUS or group A beta-hemolytic streptococci. Characteristics include pustular lesions that rupture and discharge a thin, amber-colored fluid that dries and forms a crust. This condition is commonly located on the face, especially about the mouth and nose.Hexachlorophene: A chlorinated bisphenol antiseptic with a bacteriostatic action against Gram-positive organisms, but much less effective against Gram-negative organisms. It is mainly used in soaps and creams and is an ingredient of various preparations used for skin disorders. (From Martindale, The Extra Pharmacopoeia, 30th ed, p797)Infant, Newborn: An infant during the first month after birth.Molecular Diagnostic Techniques: MOLECULAR BIOLOGY techniques used in the diagnosis of disease.Foreign-Body Reaction: Chronic inflammation and granuloma formation around irritating foreign bodies.Cellulitis: An acute, diffuse, and suppurative inflammation of loose connective tissue, particularly the deep subcutaneous tissues, and sometimes muscle, which is most commonly seen as a result of infection of a wound, ulcer, or other skin lesions.Pneumonia, Bacterial: Inflammation of the lung parenchyma that is caused by bacterial infections.Quinolones: A group of derivatives of naphthyridine carboxylic acid, quinoline carboxylic acid, or NALIDIXIC ACID.Erythromycin: A bacteriostatic antibiotic macrolide produced by Streptomyces erythreus. Erythromycin A is considered its major active component. In sensitive organisms, it inhibits protein synthesis by binding to 50S ribosomal subunits. This binding process inhibits peptidyl transferase activity and interferes with translocation of amino acids during translation and assembly of proteins.Endocarditis: Inflammation of the inner lining of the heart (ENDOCARDIUM), the continuous membrane lining the four chambers and HEART VALVES. It is often caused by microorganisms including bacteria, viruses, fungi, and rickettsiae. Left untreated, endocarditis can damage heart valves and become life-threatening.Bacterial Adhesion: Physicochemical property of fimbriated (FIMBRIAE, BACTERIAL) and non-fimbriated bacteria of attaching to cells, tissue, and nonbiological surfaces. It is a factor in bacterial colonization and pathogenicity.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Tetracyclines: Closely congeneric derivatives of the polycyclic naphthacenecarboxamide. (Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1117)Genome, Bacterial: The genetic complement of a BACTERIA as represented in its DNA.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.Streptogramin B: A specific streptogramin group B antibiotic produced by Streptomyces graminofaciens and other bacteria.4-Quinolones: QUINOLONES containing a 4-oxo (a carbonyl in the para position to the nitrogen). They inhibit the A subunit of DNA GYRASE and are used as antimicrobials. Second generation 4-quinolones are also substituted with a 1-piperazinyl group at the 7-position and a fluorine at the 6-position.Multiplex Polymerase Chain Reaction: Methods for using more than one primer set in a polymerase chain reaction to amplify more than one segment of the target DNA sequence in a single reaction.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Hospitals, Urban: Hospitals located in metropolitan areas.Aminoacyltransferases: Enzymes that catalyze the transfer of an aminoacyl group from donor to acceptor resulting in the formation of an ester or amide linkage. EC 2.3.2.Pets: Animals kept by humans for companionship and enjoyment, as opposed to DOMESTIC ANIMALS such as livestock or farm animals, which are kept for economic reasons.Nasopharyngeal Diseases: Pathological processes involving the NASOPHARYNX.