- Ear infections (otitis media)
- Alternative treatments. Physicians and parents alike are coming to the conclusion that antibiotic treatments are not only ineffective, but harmful. The American Academy of Pediatrics is suggesting that the pain of ear infection be treated first at home, since it typically lasts twenty-four hours with or without any form of treatment. Applying a warm compress to the outside of the ear is helpful, and a sock filled with grain or flaxseed that has been warmed in the microwave is safer than using a hot water bottle. Chewing gum relieves some of the pressure, as does learning how to “pop” the ears by yawning. Mullein and garlic are the herbal standbys. There are commercial ear drops that contain these two. A few drops of warm olive oil can also bring pain relief – as long as the eardrum has not been perforated. A cotton ball placed at the opening of the ear not only keeps the warm oil from draining out, but provides protection from “wind” that seems more acute during infections. Because many ear infections are the result of congestion in the Eustachian tubes, herbal decongestants and mint teas are helpful. Chamomile tea can act as an antiinflammatory and a sedative that helps to relax. Adults like hot salsa that stimulates mucus flow. Doctors at the University of Southern California found that excessive antibiotics used to treat ear infections in children contributed to the growth of yeast in the middle ear. It was only after treatment with an antifungal drug that the middle ears of these children improved. Immune suppression by way of yeast infection is another adverse effect brought on by antibiotics. Ear infections, especially in children, are usually caused by one of three bacteria: Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis. All live as part of the normal flora of the nose and throat, but an overgrowth causes infection.
- Ebola
- A viral hemorrhagic fever with an extremely high mortality rate.
- ECG (echocardiogram)
- An image of the interior of the heart, created by passing ultrasonic beams through the chest wall. The transesophageal echocardiogram is a procedure performed by placing an ultrasound probe inside the patient’s esophagus to view the heart.
- Echoviruses (enteric cytopathic human orphan viruses)
- Viruses often found in the intestinal tract along with coxsackieviruses and, sometimes, the poliovirus. Many of the echoviruses have been shown to cause a variety of diseases. About thirty different serotypes of coxsackieviruses and thirty-three serotypes of echoviruses have been identified, but the differences between the two groups are slight.
- Ecology
- The study of the interrelationships between organisms and their environments.
- Ecosystem
- A community of organisms and their natural environment.
- Ectoparasites
- Parasites that live on the body rather than inside, and include mites, bed bugs, ticks, fleas, lice.
- Edwardsiella
- A bacterium of the family Enterobacteriaceae, and associated with meningitis, septicaemia, and wound infections.
- EEG (electroencephalogram)
- The use of scalp electrodes to record the electrical activity of the brain.
- Eikinella
- A genus of bacteria having only one species, E. corrodens. Since it is part of the normal flora of the mucus membranes of the respiratory tract in humans, this bacterium is most often the cause of infections involving human bites. Such infections can be serious, leading to cellulitis, osteomyelitis, or bacteremia.
- Electrolytes
- Ionic components of the blood, consisting of sodium, potassium, chloride, and bicarbonate that are carefully regulated within the body. An electrolyte imbalance, as happens after periods of vomiting and/or diarrhea, can rapidly produce severe illness and even death. Isotonic electrolytes are concentrations of metabolic ions (sodium, potassium, and chloride) in the same concentrations as found inside the cell. Electrolytes readily conduct an electric current when dissolved.
- Elementary bodies
- The infectious stage in the life cycle of Chlamydiae.
- Elephantiasis
- A condition often produced by roundworm parasites in which obstruction to lymphatic drainage causes extreme swelling of parts of the body, often the legs, scrotum, or breast.
- ELISA (enzyme-linked immunosorbent assay)
- A technique that involves attaching an enzyme to a desired antibody, which then reacts with a fixed antigen.
- Embolus
- A clot or foreign substance carried by the flow of blood from the central circulation and lodges in a smaller vessel, causing obstruction to the flow of blood.
- Encephalitis
- An inflammation of the brain caused by various agents including viruses, bacteria, and the bite of an infected insect. The types found in North America attributed to mosquitoes are SLE (St.Louis Encephalitis), EEE (Eastern Equine Encephalitis), and CE (California Encephalitis). Another found in Asia is JE (Japanese Encephalitis), which can be a potentially deadly risk to travellers. Other forms include Venezuelan equine encephalitis and Powassan encephalitis, spread by ticks and not mosquitoes.
- Encysts
- Becomes enclosed in a sac.
- Endemic
- An infection that is prevalent in or unique to a particular place or a particular people, but in low numbers (contrast epidemic).
- Endocarditis
- An infection of the tissues lining the inside of the heart or valves in the heart. Often it is caused by a bacterium. Turbulent flow can cause wear and tear on the heart’s delicate lining, which, in turn, causes platelets to stick to these areas. Platelets also have sticky surfaces for circulating bacteria to adhere to. Everytime the teeth are brushed or dental floss is used, or dental cleansings are performed, small amounts of blood are produced. Bacteria that normally inhabit the mouth and throat can then enter the bloodstream in this manner. Bacteria that normally slide over valves now stick to platelets on the valves and other heart structures subject to the turbulent flow. As they multiply, they begin their damage. This rarely produces any pain that would normally be a warning signal. Often, it is discovered by such indirect signs as Roth spots or peculiar skin rashes. A normal heart valve will become infected if enough bacteria are injected into the bloodstream, which is often the case with IV drug abusers. Often the drug is contaminated and, if not, the water used to dissolve the drug most often is, having been taken from a tap, saliva, or yes, the toilet bowl. Often, it is Staphylococcus aureus that affects the tricuspid valve of the heart, which can then progress to pneumonia.
- Endocytosis
- A process in which a particle, for example, a virus, is taken into an animal cell. Phagocytosis and pinocytosis are two kinds of endocytosis.
- Endogenous
- From the inside. Such bacteria are those that are part of the normal flora of the host and pose a threat only if the host becomes immunocompromised.
- Endolimax nana
- A type of very small amoeba that may be pathogenic and cause arthritis in people.
- Endometriosis
- An inflammation or infection of the uterus.
- Endonuclease
- An enzyme that cuts up DNA.
- Endoparasites
- Parasites that live inside the body, e.g., amoebas, worms, or flukes.
- Endophthalmitis
- An inflammation or infection on the inside of the eyeball, a serious condition often requiring its removal.
- Endoplasmic reticulum
- The extensive array of internal membranes found in eucaryotic cellular cytoplasm, often associated with protein synthesis.
- Endospore
- A differentiated cell formed within the cells of certain Gram-positive bacteria. It is extremely resistant to heat and other harmful agents.
- Endosymbiont
- An organism that lives entirely within another organism and where both partners derive benefit from the arrangement.
- Endosymbiosis
- The hypothesis that mitochondria and chloroplasts are the descendants of ancient prokaryotic organisms from the domain Bacteria.
- Endothelial cells
- Those cells that line a body cavity or tube.
- Endotoxins
- Lipopolysaccharides which are heat-stable poisonous substances capable of producing harm to the exterior membrane of a Gram negative bacterial cell. They are not secreted, and are released only when the cell is disrupted. They are less potent and less specific than exotoxins, and they also do not form toxoids. Large quantities of exdotoxins are capable of producing hemorragic shock and severe diarrhea. Endotoxic shock symptoms include fever, increased rate of breathing and heart beat, and lowered blood pressure resulting from exposure to endotoxins associated with the outer membrane of Gram-negative bacteria (contrast exotoxin).
- Entamoeba hartmanni
- An amoeba similar to E. histolytica, but smaller.
- Entamoeba histolytica
- A type of amoeba that is often responsible for causing an infection of the intestines or liver (amebiasis).
- Enteric
- Intestinal, or having to do with the intestines. Enteric fever is a collective term given to infections caused by Salmonella typhi (typhoid fever) and by strains of S. paratyphi (paratyphoid fever). The symptoms of the paratyphoid fever are similar to those of typhoid but milder, causing fewer deaths.
- Enteric bacteria
- Members of the family Enterobacteriaceae, many of which grow in the intestinal tract.
- Enteritis
- An inflammation or infection of the intestine.
- Enterobacter
- A bacterium of the family Enterobacteriaceae, and closely related to Klebsiella, causing similar infections. The most commonly encountered species is E. cloacae, which is frequently antimicrobial resistant, thereby contributing to more serious infections.
- Enterobacteriaceae
- Bacteria often found as part of the normal intestinal flora. They are also known as coliforms. Various species of the Enterobacteriaceae are able to cause pneumonia and urinary tract infections, wound infections, and other such nosocomial (hospital acquired) infections as bacteremia and meningitis.
- Enterococcus
- Any streptococcus of the human intestines. At one time called enterococci, they are now classified in their own genus because they differ from proper strep germs. Enterococcus faecium and E. faecalis are two emerging microbes proving to have super-resistance to antibiotics. Since 1994, surveys have indicated that 8% of all reported Enterococcus illnesses are caused by drug-resistant bacteria. Pathologists fear that, soon, they will transfer their resistance to such other intestinal germs as streptococci and staphylococci.
- Enterotoxigenic strains
- Strains of Escherichia coli carrying a plasmid that enables them to make an enterotoxin.
- Enterotoxins
- Exotoxins produced by a variety of bacteria that are absorbed through the intestinal mucosa causing nausea, vomiting, and/or diarrhea.
- Enteroviruses
- Genera of viruses belonging to the family Picornaviradae that have traditionally been subdivided into the poliovirus, coxsackievirus, and echovirus groups that can infect the intestinal tract. Enteroviruses can produce many such different illnesses as meningitis, encephalitis, respiratory illness, diarrhea, severe form of conjunctivitis, Hepatitis A, and a host of other ailments, including the common cold. They can be easily be found in sewage, and are unphased by antibiotics and disinfectants. They can remain viable even after years of being frozen, and can withstand heat to 50°C (122°F). Even though they are found everywhere at all times, they seem to prefer late summer or early fall for their proliferations. Chlorination can inactivate them, but even the slightest presence of organic matter protects them, making total water purification impossible. They crave human tissue and are highly communicable, and most often spread through the fecal/oral route.
- Envelope
- The lipid covering found peripheral to the viral capsid on some virions.
- Enzyme
- A protein which, without affecting itself, accelerates a biochemical reaction that would otherwise not take place or would do so inefficiently. Enzymes are proteins, but not all proteins are enzymes. An important function of some proteins is to serve as enzymes.
- Eosinophil
- A type of white blood cell that increases in number during allergic or parasitic illnesses (eosinophilia). They have two rounded projections and are filled with granules that stain bright red with the dye eosin. They comprise about 1-3% of the total white blood cell population.
- Epidemic
- A term referring to any disease, injury, or health-related event that occurs suddenly among more people in a particular region more than is normal. Others define it as the joining to gether of populations because they share the same disease. But an epidemic also acts as a natural selection by killing some of the population, but sparing others. In such a case as this, an epideminc links separate populations into a single evolutionary unit. A pandemic, on the other hand, is an epidemic that occurs simultaneously in many different parts of the world. There are five major factors that influence how an infectious disease moves from one geographical area to another: war, trade, travel, urbanization, and gobal climate change (contrast endemic).
- Epidemiology
- The study of disease, its occurrence, control, and effects on the environment. The study of the incidence and prevalence of disease in populations. A person who studies this area is known as an epidemilogist.
- Epiglottitis
- Infection of the tissues that normally cover the trachea during swallowing, frequently producing a severe croup.
- Epiphyte
- A nonparasitic plant growing upon another plant for support.
- Epithelium
- The layer of epithelial cells covering internal and external body surfaces. It is the nonvascular (no blood vessels) cellular layer covering internal and external body surfaces.
- Epitope
- An antigenic determinant.
- Epstein-Barr virus (EBV)
- A herpesvirus transmitted by saliva. It grows in epithelial cells and in B cells, causing glandular fever (infectious mononucleosis), and then remaining in the body in a latent form until the hosts defence system weakens. There is also a strong connection between EBV and cancer of the nose and throat in China and of Burkitt lymphoma in Africa and Asia.
- Erysipelas
- A form of cellulitis caused by the bacterium Streptococcus pyogenes, often affecting the face and characterized by fever, prostration, and occasionally septicemia. It is transmitted via open wounds. Another genus, Erysipelothrix, has only one species E. rhusiopathiae which causes local skin lesions (erysipeloid) or a more serious systemic illness.
- Erythema
- Skin redness resulting from dilation of the capilaries.
- Erythrocyte
- A red blood cell.
- Eschar
- A deep dark crust or scab that develops at the site of such an injury as burns.
- Escherichia
- A bacteria of the genera Enterobacteriaceae and known most often as simply E. coli. It is one of the predominant bacteria normally found in the intestinal tract and is used as an indicator organism in determining the fecal content of water and food. Since most of the current work in molecular biology and recombinant DNA uses E. coli, more is known about this organism than any other. Varying degrees of pathogenicity exist within the species. Certain strains of E. coli called enterotoxigenic E.coli (ETEC) produce enterotoxins that function like those produced by the cholera bacillus, V. cholerae. These strains are the most frequent cause of infectious diarrhea in the world. One such strain, E. coli 0157:H7 (Escherichia coli Hemorrhagic Colitis 0157:H7) causes acute hemolytic anemia and renal failure made especially dangerous because of its resistance to many antibiotics.
- Espundia
- A chronic destructive disease of the nose and mouth, found chiefly in Brazil. It is caused by the protozoan parasite Leishmania braziliensis.
- Etiologic agent
- The cause of a specific infection.
- Eubacteria
- True bacteria, being both smaller and less complex than eucaryotic cells. They have rigid cell walls and are shaped as spheres, rods, or helices. They are found virtually everywhere in every kind of condition. Although many important human diseases are attributed to bacteria, most are not able to cause disease. Without bacteria, many beneficial environmental changes would not occur, including the decomposition of waste products and toxic chemicals. Two groups of small bacteria called Rickettsiae and Chlamydiae are able to multiply only inside living eucaryotic cells. Because of their size and dependency on living host cells, they are often grouped with viruses. They are now best considered as small parasitic bacteria.
- Eukarya
- The phylogenitic domain containing all eukaryotic organisms.
- Eukaryote
- The class of living things which consist of cells with nuclei that include all organisms except bacteria (contrast prokaryote).
- Eutrophication
- The process by which a body of water becomes so rich in dissolved nutrients that the resultant algal growth depletes the water of oxygen supplies needed by other organisms. It is the nutrient enrichment of water from detergents, fertilizers, and animal manures which causes overgrowth of algae and subsequent depletion of oxygen.
- Ewingella
- A bacterium of the family Enterobacteriaceae, associated with septicaemia, wound infections, and UTIs (urinary tract infections).
- Exanthema
- A skin rash.
- Exoenzyme (extracellular enzyme)
- An enzyme that is synthesized in a cell, but crosses the cell membrane to act in the periplasmic space or the cell’s immediate environment.
- Exogenous infection
- An infection acquired from a source other than the patient’s own commensal flora.
- Exotoxins
- Potent poisonous proteins formed and secreted by a bacterial cell. They are heat labile (unstable) and the most poisonous substances known to man. Diphtheria, botulism, and tetanus are the most common exotoxins produced by bacteria. It is also toxin released extracellularly. (contrast endotoxin)
- Expoential growth
- The growth of a microorganism where the cell number doubles within a fixed time period.
- Exudate
- A secretion from vessels that collects in body tissues and spaces, or from the tissue that is discharged outside the body. It is also scaping fluid or semifluid material that oozes from a space that may contain serum, pus, and cellular debris.
