Exam 1 Cont. Flashcards
Inability to make attachment proteins or adhesins
Avirulent
Extracellular enzymes are secreted by
The pathogen
Hyaluronidase and collagenase break down ____ which allow bacteria to ____
Tissue; penetrate deeper
Toxins are chemicals that
Harm tissues or trigger host immune responses
Two types of toxins
Exotoxins
Endotoxins
Examples of exotoxins
Cytotoxins
Neurotoxins
Enterotoxins
Example of endotoxin
Lipid A
Antiphagocytic factors prevent
Phagocytosis via bacterial capsule and chemicals
Stages of infectious disease
- Incubation period
- Prodromal period
- Illness
- Decline
- Convalescence
Incubation period
Between infection and 1st symptoms or signs
Prodromal period
Short period of generalized, mild symptoms
Illness
Most severe stage, signs/symptoms most evident
Decline
Body slowly returns to normal
Immune system vanquish pathogens
Convalescence
Patient recovers from illness
Portals of exit
Bodily secretions Blood Vaginal secretions Breastmilk Bodily wastes
Modes of transmission
Contact
Vehicle
Vector
Perinatal
Contact transmission
Direct, indirect or droplet
Fomite
Inanimate object involved in indirect transmission
Vehicle transmission
Air, water, foor, fecal-oral bodily fluids
Vector transmission
Arachnid or insect, biological or mechanical
Perinatal transmission
Mom to baby (placenta/breast milk)
Arthropod vectors
Animals that carry pathogens
Mechanical vectors
Only carry pathogen
Biological vectors
Serve as host for pathogen
Disease vectors belong to
Arachnids
Insects
_____ are most important arachnid vectors
Ticks
____ do NOT cause disease
Spiders
_____ are most important insect vector
Mosquitoes
____ is Most important and common of ALL vectors
Mosquitoes
Incidence
Number of NEW cases
Prevalence
Number of TOTAL cases
Endemic
Disease that normally occurs at regular intervals
Sporadic
Few scattered cases
Epidemic
Occurs at greater frequency than is usual
Pandemic
Occurs on more than one continent
Descriptive epidemiology
Tabulation of data and identify index case
Index case
First cases of the disease
Tabulation of data
Record location and time of disease
Collect patient info
Nosocomial infections
Acquired in health-care settings
Exogenous nosocomial infection
Pathogen acquired from HC environment
Endogenous nosocomial infection
Pathogen arises from microbiota bc of factors in HC setting
Iatrogenic
From modern medical procedures
most effective way to reduce nosocomial infections
Hand washing
Notifiable diseases
Diseases for which HC workers are required to report to state health departments
Foodborne illnesses due to comsumption of
Spoiled foods/foods containing harmful microbes or their products
Two categories of food poisoning
Food infections
Food intoxications
Food infections
Consumption of living microorganisms
Food intoxications
Consumption of microbial toxins, NOT microbe
Most common place foodborne illnesses come from
Restaurants
Waterborne illnesses caused by consuming
Contaminated water
Waterborne diseases in US
Rare
1 MC foodborne pathogen
Norovirus
2 MC foodborne illness
Salmonella