Communicable Diseases Flashcards
Agent
Bacteria, viruses, fungi, parasites
Reservoir
Fomites (surfaces, clothing)
Animals
Insects
People
Soil
Water
Food
Port of exit (from the reservoir)
Skin, consumption, blood secretions, excretions, through bodily fluids (mosquitos bite), aerosis (gas in air)
Mode of transmission
Contact (direct/ indirect), inhalation (droplet/ airborne), ingestion
Port of entry
Broken skin, respiratory system, mucous membrane, digestive system
Susceptible host
any person who has the potential to be exposed to the agent
Sometimes host also serves as a reservoir
Example of susceptible hosts
immune deficiency, diabetes, burns, surgery, age
Ways to break the chain of infection
Source reduction
Chemical larviciding
Biological control- fungi/ nematodes
Handwashing
Vaccinations
nets, screens, genetic modification of malaria vectors
Elements of Effective Screening
Reliability
Validity
Reliability
Whether something can reproduce the same results multiple times
Sensitivity
True positive
Proportion of pt with a disease who test positive
correctly identifies every person who HAS the target disorder
Specificity
*True Negative- Less false positives
Proportion of pt without the disease who test Negative
Correctly identifies every person who DOES NOT have the target disorder
A prevention strategy encouraing electricians and plumbers to wear masks in an area where hantavirus is endemic interrupts which stage in the chain of infection?
Portal of entry
When we are concerned about the infectivity of a pathogen, which component of the epidemiological triangle does it fall under?
Agent
What do we call a living organism that aid in transmission of pathogens between humans
Vectors
