U3 Immunity: Transmission of diseases Flashcards
What are the categories of communicable diseases?
- Contagious communicable diseases (can be passed directly from one person to another
- Contagious diseases spread by vectors (agents capable of transferring a disease causing organism from one person to another)
What are the different methods of transmission of pathogens?
- Transmisison by contact
- Ingestion of contaminated food or drink
- Transfer of body fluids
- Infection by droplets
- Airborne transmission
- Transmission by vectors
What is transmission of pathogens by contact?
Spead of a pathogen by actual physical contact
What are the two types of contact that pathogens can be transmitted by?
- Direct contact: actually touching an infected person
- Indirect contact: touching an object that has been touched by an infected person
What are three examples of diseases that can be transmitted by direct contact?
- Skin infections
- Conjunctivitis
- STIs
What is transmission of pathogens by ingestion of contaminated food or drink?
Ingesting food or drink contaminated with pathogens
What are three examples of diseases that can be transmitted through ingestion of contaminated food or drink?
- Dysentery
- Typhoid
- Salmonella
What is transmission of pathogens by body fluids?
When body fluids from an infected person come into contact with the mucus membranes (nose, mouth, etc) or the bloodstream of an infected person, risking pathogens entering the body of that person
What are two examples of diseases that can be transmitted by the transfer of body fluids?
- HIV
- Hepatitis
What is infection by droplets?
When tiny droplets of moisture containing pathogens are emitted when breathing, talking, sneezing or coughing that are breathed in by others
What are three examples of diseases transmitted by infection by droplets?
- Influenza
- Colds
- COVID-19
What is the airborne transmission of pathogens?
When viruses and bacteria remain viable when moisture in exhaled droplets evaporate and can cause infection when inhaled
Why is airborne transmission more effective than infection by droplets?
As virus particles are lighter than moisture droplets, they remain viable for a greater distance
What is transmission of pathogens by vectors?
When pathogens are transferred by other animal such as ticks or mosquitos
What are the two ways in which vectors can transfer pathogens?
- Direct transfer of the pathogen (mosquito)
- Spreading pathogen to food or water than is later ingested (house flies)
