The BACTERIA, fungi, and other microorganisms naturally present within the environment of the healthy body. Normal flora exist on the surface of the SKIN, within natural cavities such as the NOSE and MOUTH, in the gastrointestinal tract, and in the reproductive tract. These beneficial microbes participate in the body’s IMMUNE RESPONSE, digestive functions, and reproductive functions, among others.
Normal flora microbes exist in a balance that prevents one type of MICROBE from overpowering another. Circumstances that change this balance may allow illness to develop. Antibiotic therapy targets bacteria, for example, though antibiotics cannot distinguish between normal flora and pathogenic bacteria. So ANTIBIOTIC MEDICATIONS, particularly broad-spectrum antibiotics, kill bacteria in the gastrointestinal tract and the reproductive tract at the same time they kill pathogenic bacteria. The result may be DIARRHEA or yeast VAGINITIS.
Resource: Facts On File Encyclopedia Of Health And Medicine
What is a virus - definition Virus - an infectious PATHOGEN that must invade a host cell to replicate, technically called an obligate intracellular PARASITE. A virus is a particle of living material that contains an inner core of nucleic acid (DNA or RNA), called the genome, encased in an outer shell of protein, called a capsid. Some viruses contain a
A VIRUS family that causes INFECTION of mucous membrane tissues throughout the body. Adenoviruses are responsible for a wide range of illness including upper respiratory infection, viral CONJUNCTIVITIS, GASTROENTERITIS, and URINARY TRACT INFECTION (UTI). These infections primarily affect children age 10 and younger. Infection with one adenovirus confers
A parasitic INFECTION of the gastrointestinal tract. The PARASITE responsible is Entamoeba histolytica, a single-cell organism (an ameba) that enters the body by drinking water or eating food that contains E. histolytica in cyst form. The cyst is a protective encasing within which the ameba may sustain itself in a dormant stage for weeks to months outside a
Antibiotic medications - Drugs that kill BACTERIA and certain other microorganisms. Antibiotic medications are the mainstay of treatment for bacterial INFECTION. Broad-spectrum antibiotics are capable of killing numerous types of bacteria; narrowspectrum antibiotics kill specific types or strains of bacteria. There are seven primary classifications of
Drugs that kill fungi (yeast). Antifungal medications are available for topical or systemic treatment. Some fungal infections require both. Antifungal medications work through various mechanisms to interfere with the ability of fungi to survive or reproduce. Broadspectrum antifungal medications are effective for treating a variety of fungal infections;
Antiviral medications - medications to shorten the course and lessen the severity of illness due to viral INFECTION as well as reduce viral shedding to minimize contagiousness. Some antiviral medications are able to prevent viral infection from developing after exposure to the VIRUS. Antiviral medications mark a fine line because they must destroy viruses
Anthrax (disease) - an illness resulting from INFECTION with the bacterium Bacillus anthracis. Anthrax is a naturally occurring infection among wild and domestic livestock (such as cows, sheep, goats, and antelope). Anthrax is rare in people in the United States, though more common in people who live, work, or travel to countries where anthrax is more
An illness that results from INFECTION with the parasitic protozoan Babesia microti. Most people who have babesiosis do not have symptoms; the infection causes illness primarily in people who are IMMUNOCOMPROMISED or who have had SPLENECTOMY (surgical removal of the SPLEEN). The bite of the Ixodes tick, found in the northeastern United States, is the mode
What is bacteria and definition of bacteria Bacteria - single-cell microorganisms (microbes). Bacteria are the most ancient and primitive life forms known, with fossils dating back more than 3 billion years. A bacterium’s structure is very simple, consisting of a rigid cell wall that supports and contains the cytoplasm, fragments of RNA, and a single
What is Botulism Botulism is a potentially life-threatening illness resulting from INFECTION with the anaerobic bacterium Clostridium botulinum. The BACTERIA are naturally present in soil, where they encase themselves in spores. In the body, the bacteria release a toxin that blocks the release of acetylcholine, a NEUROTRANSMITTER that facilitates NERVE