• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/62

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

62 Cards in this Set

  • Front
  • Back
Pathology
Study of disease
Etiology
Study of the cause of a disease
Pathogenesis
Development of disease
Infection
Colonization of the body by pathogens
Disease
An abnormal state in which the body is not functionally normally
Normal microbiota
permanently colonize the host
Transient microbiota
may be present for days, weeks, or months
Symbiosis
is the relationship between normal microbiota and the host
Commensalism
one organism is benefited and the other is unaffected.
Corynebacteria (surface of eye)
Mutualism
both organisms benefit.
Escherichia coli (vitamin K and some B vitamins)
Probiotics : live cultures applied for beneficial effect Lactobacillus
Parasitism
one organism is benefited at the expense of the other.
(any pathogen)
Locations of normal microbiota
may act as opportunistic pathogens
Streptococcus pneumoniae
Staphylococcus aureus
Escherichia coli
Probiotics:
live microbes applied to or ingested into the body, intended to exert a beneficial effect.
Microbial antagonism
is competition between microbes
Koch’s Postulates (etiology of disease)
All animals with disease must have suspected agent

Isolate suspected agent and Grow in Pure culture

Inoculate healthy susceptible animal which must come down with same disease

Re isolate suspected pathogen

ex: Bacillus anthracis cause of anthrax
Symptom
A change in body function that is felt by a patient as a results of disease (pain, malaise)
Sign
A change in a body that can be measured or observed as a result of disease. (temperature, swollen lymph)
Syndrome
A specific group of signs and symptoms that accompany a disease. (used to diagnose disease together with lab results)
Communicable disease
spread from one host to another
ex:chickenpox, measles, genital herpes, AIDS
Contagious disease
easily spread from one host to another
ex; chickenpox, measles
Non communicable disease
not transmitted from one host to another rabies, tetanus
Incidence
Fraction of a population that contracts a disease during a specific time. (indicator of spread)
ex:
11,724 AIDS cases reported yearly July to June
Prevalence
Fraction of a population having a specific disease at a given time (old and new cases) indicates how long a disease effects a population
ex:
281,000 living with AIDS in U.S.
Sporadic disease
occurs occasionally in a population
Hepatitis C viral (51), mumps (40), measles (42)
Endemic disease
constantly present in a population
tuberculosis in urban areas
Epidemic disease
acquired by many hosts in a given area in a short time
influenza
Pandemic disease
worldwide epidemic
AIDS
herd immunity
Rate of spread and number people affected are determined by immunity. Advantage of vaccination is that if most of population is vaccinated , unvaccinated people will be protected
Acute disease
symptoms develop rapidly but lasts short time influenza (influenza virus)
acute bacterial endocarditis (Staophylococcus aureus - mouth)
Chronic disease
disease develops slowly but likely to be continual or recurrent
ex;
infectious mononucleosis (Epstein Barr Virus), tuberculosis (Mycobacterium tuberculosis)
hepatitis (Hepatitis B Virus)
Latent disease
disease with a period of no symptoms when the causative agent is is inactive
ex:
shingles (Varicella-Zoster Virus
cold sores (Herpes Simplex Virus)
Local infection
Pathogens limited to a small area of the body (Staphylococcus aureus); boil abscesses)
Systemic infection
An infection throughout the body by blood and lymph (measles)
Bacteremia
Bacteria in the blood
Septicemia
Growth of bacteria in the blood
Toxemia
Toxins in the blood (tetanus)
Viremia
Viruses in the blood (measles)
Primary infection
Acute infection (HIV) that causes the initial illness (AIDS)
Secondary infection
Opportunistic infection after a primary (predisposing) infection (Pneumocystis)
Sub clinical disease
No noticeable signs or symptoms (inapparent infection)
(Poliovirus, hepatitis A)
The Stages of a Disease
Reservoirs
continual sources of infection.
Human Reservoirs
AIDS, Measles, Poliovirus, Gonorrhea, Diphtheria, Streptococcus

Carriers may have inapparent infections or latent diseases
Animal Reservoirs
Rabies, Lyme disease, Influenza, Hantavirus

zoonoses disease of lower animals transmitted to humans
Nonliving Reservoirs
Soil Botulism, Tetanus
Contact Transmission
Direct Requires close association between infected and susceptible host

Indirect Spread by fomites (contaminated inanimate objects)

Droplet Transmission via airborne droplets (< meter)
Vehicle Transmission
inanimate reservoir (food, water, air > 1 meter)

Salmonella, Cholera, Shigellosis, Mycobacterium, Staphylococcus, Streptococcus
Vector Transmission
arthropods, especially fleas, ticks, and mosquitoes

Malaria, Lyme disease, RMSF, Dengue fever)

Mechanical- Arthropod carries pathogen on feet

Biological- Pathogen reproduces in vector
Salmonella
Transmission
Salmonella

direct (shaking hands), indirect (fomite), vehicle (food), vector (flies)

4F’s : flies, fingers, food, feces
Nosocomial
(Hospital-Acquired) Infections
acquired as a result of a hospital stay
5-15% of all hospital patients acquire nosocomial infections

contributing factors
virulence factors
antibiotic resistance

Compromised Host

Chain of transmission Dr. Nurses
Most common Nosocomial infection
UTI
Emerging Infectious Diseases
Diseases that are new (AIDS), previously seen increasing in incidence (TB), or diseases not seen in this country (West Nile Encephalitis)
Contributing factors of Emerging Infectious Diseases
Evolution of new strains (Vibrio cholerae O139, Invasive group A Streptococcus (flesh eating)

Human Intervention (Bolivian hemorrhagic fever viruses, HIV-AIDS, Ebola hemorrhagic fever)

Inappropriate use of antibiotics
nosocomial
Methicillin resistant Staphylococcus aureus and Vancomycin resistant Enterococci
XDR extensively drug resistant Tuberculosis

Changes in weather patterns (Hantavirus Pulmonary Syndrome)
Modern transportation (West Nile fever)
poverty, war, expanding human settlement (Dengue Hemorrhagic fever)
Animal control measures (Lyme disease, Bovine Spongiform Encephalopathy (prion)
Public Health failure (Escherichia coli O157:H7, Diphtheria
Epidemiologists
Study factors and patterns of people affected
age, sex, occupation, habits, socioeconomic, immunization
other diseases, common history of affected individuals

Site at which host had contact (where)

Time period of disease (when) ex: seasonal or yearly basis

Control drugs, vaccines, animal control, water treatment
sewage disposal, pasteurization, food inspection
John Snow
Collection and analysis of data regarding occurrence of disease
Retrospective - looking back

Mapped the occurrence of cholera in London

Descriptive Epidemiologist
Ignaz Semmelweis
Study of a disease using controlled experiments
Hypothesis and test hypothesis
Showed the hand washing decreased the incidence of puerperal fever

Experimental Epidemiologist
Florence Nightingale
Comparison of a diseased group and a healthy group
Showed that improved sanitation decreased the incidence of epidemic typhus

Analytical Epidemiologist
Centers for Disease Control and Prevention (CDC)
Collects and analyzes epidemiological information in the U.S.
Case reporting : Health care workers report specified disease to local, state, and national offices
Nationally Notifiable Diseases : Physicians are required to report occurrence in MMWR


Publishes Morbidity and Mortality Weekly Report (MMWR)
occurrence, incidence of Nationally notifiable diseases
Morbidity:
incidence of a specific notifiable disease
Mortality
deaths from notifiable diseases
Morbidity rate
number of people affected/total population in a given time period
Mortality rate
number of deaths from a disease/total population in a given time