Direct
Is there an intermediary during direct transmission?
No
What are the three types of indirect transmission?
Vehicle-borne transmission, vector-borne transmission, and airborne transmission.
What is a pathogen?
the "germ" that causes an infection
What is a reservoir?
place where an organism grows and reproduces
What does CFR stand for
Case fatality ratio
What is the method of direct transmission called?
Droplet Spread
How was Zika Virus first transmitted?
Through vector-borne transmission
What are the 3 corners of the epidemiological triangle?
agent, host, and environment
What does the chain of infection describe?
the route the pathogen takes from place of origin to infection of host
What is infectivity?
The capacity of an agent to enter a host and cause infection
Is there an intermediary?
No
What is a fomite?
Inanimate objects that can carry pathogens
How is COVID-19 transmitted?
through droplet spread (direct contact)
List the chain of infection
reservoir --> portal of exit --> means if transmission --> portal of entry --> susceptible host --> infectious agent
What is the difference between virulence and toxigenicity?
virulence is the capacity for an agent to produce a severe disease, while toxigenicity is the capacity of an agent to release a toxin. Not all agents produce toxins.
What do droplets consist of?
Respiratory particles (sneezes, cough, spit)
If an infected person sneezes and particles are suspended in the air for some time, and another person later walks through the infected air, can they acquire the pathogen?
Yes
What makes someone a more susceptible host compared to someone else?
people who are immunocompromised, already sick, elderly, etc. are less likely to be able fight of an infection
What is the most common portal of entry in humans?
Mucous membranes and wounds.
What does it mean to have high pathogenicity?
High pathogenicity is when an agent is much more likely to produce symptoms of a disease
How does the infected person infect a healthy person through droplet spread?
An infected person comes in direct contact with an other person, spreading respiratory dropets that can come in contact with a portal of entry on the healthy person, therefore infecting them
What is the key difference between airborne and droplet spread?
The air in airbone spread acts as an intermediary, making it indirect.
How does mask wearing affect disease transmission.
Wearing a mask prevents one from producing spreadable respiratory droplets, making it harder for droplet spread and airborne transmission to occur.
Is the reservoir also infected with the pathogen?
Sometimes it is, especially when it is a person but it does not have to be and is often left unharmed by the pathogen.
Why is influenza more common in the winter?
The influenza virus has a low resistance, so it does not survive well in warmer temperatures, making it more common in the winter months.