Lecture 2 Flashcards
Any mode or mechanism by which an infectious agent is spread from a source of infection to the host.
Transmission of Infection
A person or other living organism that can be infected by an infectious agent under natural or experimental conditions.
Host
A factor, such as a microorganism, chemical substance, or form of radiation, whose presence, excessive presence, or relative absence (deficiency diseases) is essential for the occurrence of a disease bac, virus, fungi, parasite, chemical, radiation, Vitamin deficiency
Agent
The location through which a microorganism (agent) enters the body. This may be cuts, lesions, injection sites, or natural body orifices
Portal of Entry
Transmission of a disease from mother to child either during pregnancy, childbirth, or by breastfeeding.
Not after neonatal period
Vertical Transmission
Transmission of an infection from one person to another of the same generation in the same population.
Horizontal Transmission
Transmission of an agent from a source to the host who is in close proximity.
Can be direct, indirect with source, or by droplets that travel.
Contact Transmission
The immediate transfer of an agent from a source to a host by direct contact spread.
No intermediate plays a role in transmission.
Direct Transmission
The transmission of an agent from a source to a host by suspended air particles or by animate (vector -arthropods) or inanimate (fomite any inanimate object that can transmit agent, e.g. door handles, cups, forks, tables, pens, toilet seats, old bandaids) intermediaries.
Indirect Transmission
this is a form of indirect transmission in the form of mosquito
Vector
any inanimate object that can transmit agent, e.g. door handles, cups, forks, tables, pens, toilet seats…..
Fomites
Transmission of an agent from a source to a host by spray with relatively large, short-ranged aerosols produced by sneezing, coughing, or talking. – no travelling!
Droplet Transmission
from a source to a host
agent
produced by sneezing, coughing, or talking.
short-ranged aerosols, form of droplet transmission
a type of vector transmission through a living intermediary
animate
mosquito –malaria; lyme disease. The mosquito is an example of a _____?
host
An animate (living) intermediary in the indirect transmission of an agent that carries the agent from a source to a susceptible host (mosquito –malaria; lyme disease).
vector transmission
Parenteral refers to a route of administration that involves piercing the skin or mucous membrane.
Other than through the intestine.
Injection is an example (intravenous, intramuscular, or subcutaneous).
Parenteral
Infectious agent that is shed by the infected host in feces and acquired by the susceptible host through ingestion of contaminated foods or other materials.
Fecal/Oral Transmission
Occurs when agent travels on dust particles or on small respiratory droplets. They hang in the air like invisible smoke.
Can travel on air currents over long distances.
Generated when people sneeze, cough, laugh, or exhale. Or spread deliberately.
Airborne Transmission
Any pathogen transferred to host by air becomes what?
aerosolized
transmission via oral, anal and vaginal routes is called?
Sexual Transmission
this refers to adverse effects or complications caused by or resulting from medical treatment or advice. In addition to harmful consequences of actions by physicians (not just infections).
this also refers to actions by other healthcare professionals, such as psychologists, therapists, pharmacists, nurses, dentists, and others.
Iatrogenic
A person or animal without apparent disease who harbors a specific infectious agent and is capable of transmitting the agent to others.
Carrier Host
An infectious disease that is transmissible from animals to humans – anthroposis (man ->animal)
Zoonoses
The constant presence of a disease or infectious agent within a given geographic area or population (ex: common cold).
Also refers to the usual prevalence of a given disease within such area or group. (anorexia is endemic within cheerleaders (23%), goiter in Borneo at (5%)) –imp that it is for a given area
Endemic Disease
The occurrence of more cases of disease than expected in a given area or among a specific group of people over a particular period of time.
epidemic
A histogram that shows the course of a disease outbreak or epidemic by plotting the number of cases by time of onset.
Epidemic curve
A time period when the number of cases of disease reported is greater than expected.
Epidemic period
a type of epidemic occurring over a very wide area (several countries or continents) and usually affecting a large proportion of the population.
Pandemic
Between mother and baby.
Examples: HIV, hepatitis B, hepatitis C, Group B streptoccoci, herpes.
what is this transmission?
vertical transmission
Between any two individuals who are not mother and baby.
Examples: Sexually transmitted HIV. Needle transmitted HIV (latrogenic/parentral).
what is this transmission?
horizontal transmission
An inanimate intermediate, normally consumed by the host, used in the indirect transmission of a pathogen from a source of infection to a host.
vehicle transmission
types of vehicle transmission?
airborne, foodborne, waterborne