Download Diseases and Disease Related Organisms

Diseases and Disease Related
Organisms
Diane Young, Instructor
From The Human Body in Health
and Disease Text
Disease
What is it?
Abnormal state in which part or all of the
body is not properly adjusted or is not
capable of carrying on all of its required
functions.
Causes of Disease
Direct Causes:
Disease-producing organisms
Malnutrition
Physical agents
Chemicals
Birth defects
Degenerative processes
Neoplasms
Causes Cont’d
Predisposing Causes
Age
Sex
Heredity
Living conditions and habits
Occupations
Physical exposure
Preexisting illness
Psychogenic influences
Study of Disease
Pathophysiology- the study of the
physiologic basis of disease
Includes studying both the pathologic and
physiological aspects and the need to
understand the fundamentals of each in
treating any body disorder.
Terminology
Etiology – the study of the cause or
origin of a disease
Terminology Cont’d
Diseases are on the basis of severity and
duration:
Acute – relatively severe but usually last a sort
time
Chronic – often less severe but likely to be
continuous or recurring for long periods of time.
Subacute – intermediate between acute and
chronic, not as severe as acute nor as long lasting
as chronic disorders.
Terminology Cont’d
Idiopathic – means “self-originating” or
“without known cause”
Communicable – one that can be transmitted
from one person to another
Epidemic- Occurrence of a disease among
many people in a given region at the same
time
Endemic – a disease that is found to a lesser
extent but continuously in a particular region.
Terminology Cont’d
Diagnosis – Identification of an illness
Symptoms – evidence of disease as noted by
the patient
Signs – objective manifestations the doctor or
other health care professionals can observe.
Syndrome – a characteristic group of
symptoms and signs accompanying a given
disease
Prognosis – a prediction of the probable
outcome of a disease based on the condition
of the patient and the physician’s knowledge
Terminology Cont’d
Therapy – course of treatment for a
particular disease
Prevention – methods used to stop a
disease from occuring
Modes of Infection
Microorganisms – microscopic organism
Microbe & germ – other terms for
microorganism
Parasite – any organism that lives on or within
another (host).
Parasitology – study of parasites
Pathogen – any disease causing organism
Infection – adverse effects caused by invading
pathogens
Local infection – restricted to a relatively small
area
Systemic infection – affects the whole body
Modes of Transmission
Other humans
Direct contact
Indirect contact
Insects
Deposit infectious material on food, skin or clothing
bites
Animals
Feces
Bites
Deposit infectious material on food, skin or clothing
Microbiology
The study of microorganisms
Specializations
Bacteriology
Mycology
Virology
Protozoology
Bacteria
Rod-shaped cells (bacilli) - Tetanus,
diphtheria, tuberculosis, typhoid fever
Spherical cells (cocci) – strep, staph,
diplococci (gonorrhea, meningitis)
Curved rods – (vibrio, spirillum,
spirochetes) – syphilis (spirochete).
Rickettsias and chlamydias – typhus
and Rocky Mountain spotted fever
Fungi
A large group of simple plantlike
organisms
Yeasts – single-celled form of fungi
Molds-fuzzy, filamentous form of fungi
Examples are: mushrooms, puffballs,
bread molds, and the yeasts used in
baking and brewing.
Fungi cont’d
Disease – mycotic (fungal)
Athletes foot, ringworm
Candida – thrush, vaginitis
Pnuemonia can be caused by inhalation of
fungal spores contained in dust particles
Viruses
Small microorganism that can
reproduce only within a living cell
No universal classification for viruses
Examples:
Measles, polio-myelitis, hepatitis,
chickenpox, common cold, AIDS.
THESE DO NOT RESPOND TO
ANTIBIOTICS
Protozoa
Animal-like organisms
Amebas
Ciliates
Flagellates
Sporozoa
Parasitic Worms
Roundworms
Intestinal roundworms
Pinworms
Hookworms
Others
Trichina – found in pork – causes trichinosis
Filariasis – transmitted by insect bites – found
in tropical and subtropical lands
Parasitic Worms Cont’d
Flatworms
Spread by infected, improperly cooked
meats (beef, pork, fish)
Can invade the blood, lungs, liver and
intestine
Microbial Control
Sewage and garbage disposal
Purification of water supply
Prevention of food contamination
Milk pasteurization
Aseptic Methods
Sterilization
Disinfection (bactericide and germicide)
Antisepsis
Drugs
Chemotherapy – treatment of disease by the
administration of a chemical agent
Antibiotics – chemical substance produced by
living cells
Can kill or arrest the growth of pathogenic
microorganisms by upsetting vital chemical
processes within them.
Resistant strains of pathogens – certain strep,
staph and bacilli