Modes of transmission Flashcards
What is contact transmission?
Contact transmission can be direct or indirect. Direct transmission occurs via physical contact or droplet transmission. Indirect transmission involves an object acting as an intermediate in the infection process.
What is airborne transmission (contact transmission section)?
- Small droplets of mucous with pathogen expelled (cough/sneeze).
- Can happen over distance <1m.
- Airborne transmission over distance >1m.
What is vehicle transmission?
The transmission of pathogens through vehicles such as water, food, and air.
Longer distance transmission droplets through the air is considered vehicle transmission.
How does waterborne transmission occur?
Water contamination through poor sanitation methods leads to waterborne transmission of disease.
How does foodborne transmission occur?
Food contaminated through poor handling or storage can lead to foodborne transmission of disease.
Food is an important vehicle of transmission for pathogens, especially of the gastrointestinal and upper respiratory systems.
What is vector transmission?
When a vector transmits a disease from one organism to another
Define vector
An animal (typically an arthropod) that carries the disease from one host to another.
What is a mechanical vector?
Facilitated by a mechanical vector, animal carries a pathogen from one host to another without being infected itself. E.g., fly may land on faeces and transmit the matter to food which humans then eat, making them sick.
How does biological transmission occur?
Occurs when a pathogen reproduces within a biological vector that transmits the pathogen from one host to another
What does a biological vector do?
Transmits pathogens from one host to another.
What is nosocomical transmission?
Transmission that occurs in health facilities and can’t be classed unless the patient came to the hospital for a different reason first, contracting the infection in the hospital.
What are nosocomical infections?
Infections acquired in health-care facilities including hospitals
Often connected with surgery or other invasive procedures that provide pathogen access to the portal of infection.
