The extent of pathogenecity
Virulence
An organism that can cause disease in a healthy host
Primary (Frank) Pathogen
An infection that has spread throughout the body
Systemic Infection
A disease that comes on slowly and lasts a long time.
Chronic disease
Evidence of a disease that is objective and/or measurable
Sign
The period of the infectious disease process where the patient is starting to feel bad but not have diagnosable symptoms yet.
Prodromal period
The period of illness where the patient is recovering
Convalescent period
The ability of a pathogen to establish an infection in an area of the body
Infectivity(attachment, adherence)
The ability of a pathogen to overcome aspects of the immune system and spread.
Invasiveness (overcoming phagocytosis, toxins, etc)
The area where a pathogen gets into a host
Portal of entry
A bacterial structure involved in helping an organism start an infection by helping it to stick to surfaces
Fimbrae (pili)
A bacterial structure outside of the cell wall that helps an organism evade phagocytosis
Capsule (Glycocalyx)
An extracellular enzyme that creates a fibrin clot that protects the pathogen from immune cells.
Coagulase
An extracellular enzyme that breaks down connective tissue
Collagenase and/or Hyaluronidase
An extracellular enzyme that damages red blood cells
Hemolysins
One organism benefits from an association with another organism and the other is not harmed or helped
Commensalism
A pathogen causes harm to the host, so it is a type of ______________
Parasitism
An organism that lives on dead and decaying matter is _____________________
Saprophytic
A parasite that lives on the outside of the host is an _____________
Ectoparasite
When 2 organisms benefit from their association with each other
Mutualism
The type of toxin that is part of the Gram negative cell wall
Endotoxin
Some of the most toxic natural proteins known to man
Exotoxins
A toxin like the tetanus toxin that affects the CNS causing tetanic contractions
Neurotoxin Exotoxin
A type of toxin that specifically effects cells in the intestines causing secretion of large amounts of fluids and electrolytes
Enterotoxin exotoxin
These toxins do not trigger fever, but can be neutralized by antitoxins
Exotoxins
Some pathogens can evade the immune system by changing their surface antigens, this is called __________________
Antigenic variation
Diseases transmitted to humans from animals
Zoonoses or Zoonotic diseases
A disease that is easily spread from person to person
Contagious disease
The number of new cases of a disease during a time period
Morbidity Rate
All of the cases of a disease in a population during a time period
Prevalence
A disease that can be spread from one person to another
Communicable
A disease that is spread through the air greater than 1 meter or 3 feet
Airbourne
Spread by touching a person or their infected garments, etc.
Direct contact
Transmitted by a fomite
Indirect(a fomite is an innominate object Ex doorknob)
Indirect(a fomite is an innominate object Ex doorknob)
Vector born
Transmitted through the air less than one meter or 3 feet
Droplet spread
A sudden increase in frequency of a disease in one area
Outbreak
A disease that is constantly present in a population at some level
Endemic
A disease that has spread worldwide
Pandemic
A sudden increase in frequency of a disease in several locations
Epidemic
A disease that occurs in an area every now and then
Sporadic disease
A condition with both bacteremia and septicemia with systemic inflammation
Sepsis
Giving vaccines to a population increases the ________________
Herd Immunity
Any condition or trait that makes you more susceptible an infection
Predisposing factor
Getting bacterial bronchitis or pneumonia after having had the flu
Secondary infection
A person that can spread a disease but does not have symptoms of it themselves (3 possibilities)
Passive carrier (asymptomatic)OrIncubatory carrier (exposed but not yet sick)Or convalescent carrier (recovering)
An epidemic in which there is a sudden increase in frequency and then it drops off abruptly
Common source epidemic
Sewage treatment and drinking water treatment is an example of
Breaking the connection between the source and the susceptible individuals
Responding to an epidemic by spraying to eliminate ticks or mosquitos
Breaking the connection between the source and the susceptible individuals
During an epidemic of a Zoonotic disease they send out hunters
Reduce or eliminate the source or reservoir
The primary way we increase herd immunity
Vacines
What type of response to an epidemic is it if they quarantine all cases of the disease and all that have been exposed
Reduce or eliminate source or reservoir
Causes disease once the host is impaired
Opportunistic pathogen
Resident microbes that bind host receptor and prevents pathogens from attaching
Normal microbiota
Antibacterial enzyme that targets peptidoglycan
Lysozyme
Normal microbiota is NOT ___ of all the same species no matter of location on the human body.
_comprised
Normal microbiota can NOT be found in all ___ of the body.
_locations
area where normal microbiota should not be found.
Arteries
Our normal microbiota is an important component of our immune system. Skin microbiota produce an acidic product that is inhibitory to pathogen growth.How this would protect the host?
Chemical Barrier
Identify the ways that normal microbiota protect us from pathogens.
=-secrete antimicrobial substances such as lysozyme-bind Host Cell Receptors, blocking binding sites for pathogens bind Host Cell Receptors, blocking binding sites for pathogens-consuming available nutrients-creating a mechanical barrier from pathogens-lines All surfaces that are open to the outside world (ie, Eyes, mucous membranes, GI tract, etc.)
Both organisms benefit from the relationship
Mutualism
One organism benefits with no harm or benefit to other
Commensalism
One organism lives on the other and causes harm
Parasitism
Hemolysin
Forms pores in red blood cells
Coagulase
Produces fibrin to protect bacteria from host immune response
IgA protease
Degrades the immunoglobulin IgA
Antigenic Variation
Alteration of surface proteins to hide from host immune system
Antigenic shift
Gene reassortment causing a major change
Antigenic drift
Point mutation causing slight changes
Kinase
Enzyme that dissolves clots; freeing the pathogen to spread
Enterotoxin
Causes massive amounts of fluid to leak out of cell causing diarrhea
Hyaluronidase
Breaks down loose connective tissue
What is a virulence factor?
anything that allows the organism to cause disease.
bacterial virulence factors
=-Endotoxin-M-Protein-bacterial capsule-Exoenzyme-Exotoxin-Fimbrea-Antigenic variation-AN\
By removing an organisms ability to make fimbriae which step would be affected in the development of disease (pathogenesis)?
Attachment
The ability of an organism to undergo antigenic variation would be an example of what process of pathogenesis?
Evasion and Cell Damage
The presence of pili on some organisms would be most important in which category?
Attachment in the process of pathogenesis
Category: Exotoxin
-Neurotoxin-Secreted outside of cell-Low lethal dose 50-AB 5 toxins-Entertoxin
Category: Endotoxin
-High lethal dose 50-Found in gram negative cell wall-Lipopolysacchride-Superantigens
-This organism is using an exoenzyme to increase it's pathogenicity.-This organism is able to evade phagocytosis.-This organism is secreting a protease.
Bacterial Cell
Category: Exoenzyme
=-Collagenase-Hyaluronidase-DNAse-helps pathogen invade Host cells and deeper Tissue
Category: Exotoxin
=-membrane disrupting-Superantigens-Intracellular targeting-Most commonly secreted by gram positive organism
Category: Antigenic Variation
=-major changes in spike proteins due to Gene reassortment-point mutations causing changes in the spike proteins
Category: Adhesions
=-Fimbriae-binds Host Cell Receptors-Pili-Protein or glycoproteins on surface of the pathogen-used for attachment to Host cells
Order of Disease Process
1. Incubation2. Prodromal3. Period of illness4. Period of decline5. Period of convalescence
What stage of disease do you being to feel symptoms such as muscle aches and fatigue?
2. Prodromal
Disease caused by direct effect of a pathogen
Infectious Disease
Spread from person to person
Communicable disease
Easily spread from person to person
Contagious disease
Acquired during a hospital stay
nosocomial disease
Transmitted from animal to human
Zoonotic disease
Not spread from person to person
Noncommunicable disease
No notable signs or symptoms
Subclinical
In what stage do the number of pathogens beginning to lessen and the patient begains to feel better?
4. Period of decline
Signs of Illness
=-objective and measurable-vital signs-temperature-blood pressure
Symptoms of Illness
=-subjective, something that is feltFatigue-pain-nausea
Study of geographical location and distribution of infectious diseases
Epidemiology
An agency of the United Nations; coordinates international public health issues
World Health Organization
Larger than expected number of cases
Epidemic
Epidemic that occurs worldwide
Pandemic
Seen only occasionally; without geographic concentration
Sporadic
Constantly seen in the population in certain geographic locations but at low levels
Endemic
Death from a certain disease
Mortality
Diseased state
Morbidity
Number of new disease cases in a given period of time
Incidence
New to the human population or shown an increase in cases
Emerging infectious disease
Number of individuals with a particular illness in a given population at a certain time
Prevalence
Vehicle Transmission
food, water, air
Vector Transmission
=-biological transmission-Arthropod-Mosquitos-fly landing on fecal matter then landing on your food and transmitting a disease
Contact Transmission
=-Droplet-sexual encounters-physical interaction-touching-Kissing-includes direct and indirect modes-person to person transmission
Inanimate object
Fomite
Disease carried by animals and transferred to humans
Zoonotic
Disease acquired in the hospital
Healthcare associated infection-nosocomial
Passing along a disease when you don't know you have it
Carrier
Example:-Sexual contact-Shaking someone's hands
Direct transmission
Example:-Sneezing in close proximity
Droplet transmission
Example:-Malaria contracted a mosquito bite
Vector transmission
Example:-Pathogen carried on a dust particle-Water making people sick
Vehicle transmission
Example:-Pathogen on an elevator button and makes you sick
Indirect contact transmission