Chiggers Glossary of TermsThe following are health and medical definitions of terms that appear in the Chiggers article.
Bacteria: Single-celled microorganisms which can exist either as independent (free-living) organisms or as parasites (dependent upon another organism for life). Bacterial: Of or pertaining to bacteria. For example, a bacterial lung infection. Bacterium: The singular of bacteria. Blister: A collection of fluid underneath the top layer of skin (epidermis). One that is more than 5 mm in diameter with thin walls and is full of watery fluid is called a bulla or a bleb. There are many causes of blisters including burns, vesicant agents, friction forces, and diseases of the skin. Calamine: An astringent made from zinc carbonate or zinc oxide, usually used in lotion form to treat skin problems that cause itching or discomfort. Chiggers: The larvae of one type of mites, of the family Trombiculidae. The larvae, or juvenile forms, feed on vertebrates such as humans, while the adult mites feed on soil. Chigger bites produce a red welt accompanied by an intense and unrelenting itch. Chiggers are so tiny that they can barely be seen with the naked eye. However, when they are present in a group, they may be noticed on the skin due to their red color. When chiggers bite humans, they inject a digestive enzyme into the host skin that destroys tissue. It is this tissue, and not blood, that serves as food for the chiggers. Chiggers have delicate mouth parts that typically can enter human skin only at areas where the skin has folds or wrinkles. Most chigger bites occur around the ankles, the back of the knees, the crotch, under the belt line and in the armpits. The chigger bite itself goes unnoticed, and the itching may last for days to weeks. Compression: 1. The act of pressing together. As in a compression fracture, nerve compression, or spinal cord compression. Corticosteroid: Any of the steroid hormones made by the cortex (outer layer) of the adrenal gland. Cortisol is a corticosteroid. Crotch: A nonmedical term in common usage for the region where the legs come together, the place where the lower limbs divide. Encephalitis: Inflammation of the brain. Encephalitis occurs, for example, in 1 in 1,000 cases of measles. It may start (up to 3 weeks) after onset of the measles rash and present with high fever, convulsions, and coma. It usually runs a blessedly short course with full recovery within a week. Or it may eventuate in central nervous system impairment or death. Endemic: Present in a community at all times but in relatively low frequency. Something that is endemic is typically restricted or peculiar to a locality or region. Enzymes: Proteins that act as a catalysts in mediating and speeding a specific chemical reaction. Febrile: Feverish. Feeding tube: See: Enteral nutrition. Gram-negative: Gram-negative bacteria lose the crystal violet stain (and take the color of the red counterstain) in Gram's method of staining. This is characteristic of bacteria that have a cell wall composed of a thin layer of a particular substance (called peptidoglycan). Groin: In anatomy, the area where the upper thigh meets the trunk. More precisely, the fold or depression marking the juncture of the lower abdomen and the inner part of the thigh. Infection: The growth of a parasitic organism within the body. (A parasitic organism is one that lives on or in another organism and draws its nourishment therefrom.) A person with an infection has another organism (a "germ") growing within him, drawing its nourishment from the person. Intracellular: Within a cell. In contrast to extracellular, meaning outside a cell. Itching: An uncomfortable sensation in the skin that feels as if something is crawling on the skin or in the skin, and makes the person want to scratch the affected area. Juvenile: Between infantile and adult as, for example, in juvenile rheumatoid arthritis (onset before age 16 years) and juvenile diabetes (type 1 diabetes). Mite: A tiny eight-legged creature belonging to the Order Acarina related to spiders and ticks. Some mites live freely and others as parasites. Mites can attack plants and animals, carry disease, and cause allergies. acaricide. Mouth: 1. The upper opening of the digestive tract, beginning with the lips and containing the teeth, gums, and tongue. Foodstuffs are broken down mechanically in the mouth by chewing and saliva is added as a lubricant. Saliva contains amylase, an enzyme that digests starch. 2. Any opening or aperture in the body. The mouth in both senses of the word is also called the os, the Latin word for an opening, or mouth. The o in os is pronounced as in hope. The genitive form of os is oris from which comes the word oral. Nail: In medicine, there are two types of nails. One is just a plain old metal nail used to hold 2 or more pieces of bone together, for example, after a fracture. The other type of nail is the horny plate on the end of the finger or toe. Each nail anatomically has a body, lateral nail folds (on the sides), a lunula (the little moon-shaped feature at the base), and a proximal skin fold (at the base). Nymph: A nymph is a stage in the life cycle of certain arthropods, as ticks and lice. (Not all nymphs are in Greek mythology.) Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pain has both physical and emotional components. The physical part of pain results from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it can be more diffuse, as in disorders like fibromyalgia. Pain is mediated by specific nerve fibers that carry the pain impulses to the brain where their conscious appreciation may be modified by many factors. Pimple: A small papule or pustule. Pimples are sebaceous glands (oil glands) that are infected with bacteria, become inflamed, and fill with pus. Pimples are due to overactivity of the sebaceous glands located at the base of the hair follicles, especially on the face, back, chest, and shoulders. They are a visible and palpable hallmark of acne. Pus: A thick whitish-yellow fluid which results from the accumulation of white blood cells (WBCs), liquified tissue and cellular debris. Pus is commonly a site of infection or foreign material in the body. Rickettsia: A member of a group of microorganisms that (like viruses) require other living cells for growth but (like bacteria) use oxygen, have metabolic enzymes and cell walls, and are susceptible to antibiotics. Rickettsiae cause a series of diseases named for the American pathologist Howard Ricketts who discovered that ticks spread Rocky Mountain spotted fever and then isolated from the blood of infected animals and eggs of infected ticks the microorganism responsible for Rocky Mountain spotted fever, typhus, trench fever and other similar conditions. While in Mexico in 1910 studying a typhus epidemic, Ricketts contracted the disease and died at age 39.(See Rickettsial diseases). Scrub: 1. As a verb, to wash the hands and forearms very thoroughly, as before engaging in surgery. To scrub implies the use of a brush (and often an implement to clean under the nails). To scrub, to scrub in (on a surgical procedure), and to scrub up are synonymous. Scrub typhus: A mite-borne infectious disease caused by a microorganism, Rickettsia tsutsugamushi, characteristically with fever, headache, a raised (macular) rash, swollen glands (lymphadenopathy) and a dark crusted ulcer (called an eschar or tache noire) at the site of the chigger (mite larva) bite. This disease occurs in the area bounded by Japan, India, and Australia. Known also as Tsutsugamushi disease, mite-borne typhus, and tropical typhus. Symptom: Any subjective evidence of disease. Anxiety, lower back pain, and fatigue are all symptoms. They are sensations only the patient can perceive. In contrast, a sign is objective evidence of disease. A bloody nose is a sign. It is evident to the patient, doctor, nurse and other observers. Typhus: One of a group of acute infections caused by rickettsiae, transmitted by arthropods (lice, fleas, mites), and characterized by severe headache, chills, high fever, stupor, and a rash. The four main entities making up the group are epidemic typhus, its recrudescent form (Brill-Zinsser disease), murine typhus, and scrub typhus. Called also typhus fever. See also: Brill-Zinsser disease; Epidemic typhus; Murine typhus; Scrub typhus.
|
Women's Health
Find out what women really need.
From WebMD
Healthy Resources
Featured Centers
- Eating Out? Cut Calories, Heartburn
- 5 Good Ways to Save Money on Medicine
- 8 Ways to Treat Your Allergies
Health Solutions From Our Sponsors
Chiggers
Rash Overview
Rash is a general, nonspecific term that describes any visible skin outbreak. Rashes are very common in all ages, from infants to seniors, and nearly everyone will have some type of rash at some point in their life. There are a wide variety of medical diagnoses for skin rashes and many different causes. It is not possible to fully cover every type of rash in such an article. Therefore, special mention has been given to some of the most common types of rashes. A dermatologist is a medical provider who specializes in diseases of the skin and may need to be consulted for rashes that are difficult to diagnose and treat.
While there are many different types, rashes may basically be divided into two types: infectious or noninfectious.
Noninfectious rashes include eczema, contact dermatitis, psoriasis, seborrheic dermatitis, drug eruptions, rosacea, hives (urticaria), dry skin (xerosis), and allergic dermatitis. Many noninfecti...
Featured Topics
Medical Dictionary
Pill Identifier on RxList
- quick,
easy,
pill identification
Find a Local Pharmacy
- including
24 hour
pharmacies

