Bacilli (sing. bacillus)
Bacteria that have a rod shape
Cocci (sing. coccus)
Bacteria that have a round shape
Contagious
Capable of being transmitted directly or indirectly from one person to another
Culture
The propagation of a mass of micoorganisms in a laboratory culture medium
Culture medium
A mixture of nutrients on which microorganisms are grown in the laboratory
False-negative
A test result denoting that a condition is absent when it is actually present
False-positive
A test result denoting that a condition is present when it is actually absent
Immunization
In microbiology, the act of placing a culture in a chamber (incubator) that provides optimal growth requirements for the multiplication of the organisms, such as the proper temp, humidity, and darkness
Incubation period
The interval of time between the invasion by a pathogenic microorganism and the appearance of first symptoms of the disease
Infectious disease
A disease caused by a pathogen that produces harmful effects on its host (also known as a communicable disease)
Inoculate
To introduce microorganisms into a culture medium for growth and multiplication
Microbiology
The scientific study of microorganisms and their activities
Mucous membrane
A membrane lining body passages or cavities that open to the outside
Normal flora
Harmless, nonpathogenic microorganisms that normally reside in many parts of the body but do not cause disease
Resistance
The natural ability of an organism to remain unaffected by harmful substances in its environment
Sequela
A morbid (secondary) condition occurring as a result of a less serious primary infection
Smear
Material spread on a slide for microscopic examination
Specimen
A small sample or part taken from the body to show the nature of the whole
Spirilla (sing. spirillum)
Bacteria that have a spiral or curved shape
-cocci
berry-shaped
-immuno
immune
micro-
small
bi/o
life
-ology
study of
An infection is
An invasion of pathogens
Droplet Infection
Refers to an infection that is indirectly transmitted by tiny contaminated droplets of moisture expelled from the upper respiratory tract of an infected individual. (Breathing, talking, coughing, sneezing)
Stages of an infectious Disease
1. The infection
2. The incubation period
3. The prodromal period
4. The acute period
5. The decline period
6. The convalescent period
What it is the incubation period
Interval of time between the invasion by a pathogenic microorganism and the appearance of the first symptoms of the disease. Ranges from a few days to several months; During this time the pathogen is growing & multiplying
What is the prodromal period
A short period in which the first symptoms that indicate an approaching disease occur. Headache & a feeling of illness are common symptoms.
What is the acute period
When the disease is at its peak and symptoms are fully developed. Fever is a common symptom
What is the convalescent period
The stage in which the patient regains strength and returns to a state of good health
Bacteria
Microscopic single-celled organisms; of the 1700 species known to dwell in humans, only approx. 100 produce human disease
Smallest living organisms
Viruses
Examples of infectious diseases caused by viruses
Influenza, chickenpox, rubeola (measles), rubella (German measles), mumps, poliomyelitis, smallpox, rabies, herpes simple, herpes zoster, yellow fever, hepatitis, common cold, most upper respiratory diseases
How is Syphilis (spirilla) diagnosed?
Using serologic tests performed on the serum of the blood
Where in the body is E. Coli normally found?
Normal flora of the large intestine
Diseases caused by by bacilli include...
Botulism, tetanus, gas gangrene, gastroenteritis produced by Salmonella food poisoning, typhoid fever, pertussis (whooping cough), bacillary dysentery, diphtheria, tuberculosis, leprosy, and plague
Infectious diseases caused by diplocci
Pneumonia, gonorrhea, and meningitis
Diseases caused by Streptococci
Sore throat (strep throat), scarlet fever, rheumatic fever, pneumonia, puerperal sepsis, erysipelas, & skin conditions such as carbuncles & impetigo
Staphylococcus aureus is commonly associated with what pathologic conditions
boils, carbuncles, pimples, impetigo, abscesses, staphylococcus food poisoning, and wound infections...usually cause pus
What is the stage of a Microscope
Is the flat horizontal platform on which the microscope slide is placed
Substage condenser
A lens system between the light source and object. Popular condenser is the Abbe condenser. Collects concentrates the light rays and directs them up, bringing them to a focus on the object so that it is well illuminated.
Diaphragm of a microscope
Controls the amount of light focused on the object
Coarse adjustment
Is used first to obtain an approximate focus quickly
Fine adjustment
Is used to obtain the precise focusing necessary to produce a sharp, clear image
Low-power objective lens
Has a magnification of 10x
High-power objective lenses
Is known as the "high-dry objective" because it does not require the use of immersion oil; it has a magnification of 40x
Oil-immersion objective
Has the highest power of magnification, which is 100x
What is the purpose of oil?
The oil provides a path for the light to travel on between the slide and the lens and prevents the scattering of light rays, which permits clear viewing of very small structures. Also improves the resolution of the objective lens and provides sharp detail
Care of the microscope
1. Always carry with two hands
2. Do not touch the lens
3. Keep covered to protect from dust
4. Periodically clean the microscope
5. After each use, wipe metal stage clean
6. Keep all lenses spotlessly clean with special cleaner
7. Keep the light source f
If there is a delay in processing a specimen what could happen
May cause the death of pathogens or overgrowth of the specimen
What is the function of the transport medium
Prevents drying of the specimen & preserves it in its original state until it reaches its destination
To prevent extraneous microorganisms from contaminating the specimen...
All supplies used must be sterile and the specimen should not contain microorganisms from areas surrounding the collection site.
Where are specimens collected from
throat, nose, wounds, cervix, vagina, urethra, and rectum
What is the advantage of the direct antigen ID test
That it provides the physician with immediate test results rather than requiring an overnight culture
Where do you collect a wound specimen?
Must be collected from within wound, rather than from surface - to obtain accurate & reliable test results.
Types of Collection & Transport systems
Culturette
Starswab II
Examples of Rapid strep tests
Q Test Strep
Clearview Strep A
Quick Vue In-Line Strep A
If a pathogen is susceptible to an antibiotic
Clear zone without bacterial growth around disc - indicates antibiotic if effective against the pathogen
If pathogen is resistant to an antiobiotic
No clear zone around disc - Indicates antibiotic was unable to kill the pathogen
Gram-positive bacteria are what color?
They exhibit a purple color
Gram-negative bacteria are what color?
Exhibit a pink or red color