MMI Topic 11 Flashcards
What is epidemiology
study of the incidence, distribution and spread of disease within populations
What is prevalence
the number of infected individuals in a population at a given time
What is incidence
the number of new cases of disease within a certain time period
What is a reservoir
a place where a pathogen lives and multiplies and can serve as a source from which individuals can be infected
What is a mode of transmission
how the pathogen gets from the reservoir to a susceptible host
Describe direct contact (examples?)
a mode of transmission that requires physical contacts between hosts
ex. handshake, kiss, etc
Describe indirect contact (examples?)
Mode of transmission that is spread by non-living items (fomites)
ex. bedding, toothbrush. needles
Describe communicable diseases (examples?)
Diseases that spread from one host to another host
ex. chicken pox
Describe non-communicable diseases (examples?)
Diseases that spread from a source other than another host
ex. soil bacteria?
Describe droplet contact (examples?)
Transmission via sneeze, cough, laughing, exhaling
What is zoonosis
A disease that can be transmitted to humans from animals
What are kissing bugs
vectors for trypanosoma cruzi. they are biological vectors because the pathogen reproduces within the vector (i.e. the vector is part of the pathogens lifecycle)
What is a vector
a organism that carries a pathogen between hosts
What is a fomite
a non-living object capable of carrying infectious organisms and transferring them from one individual to another
Describe a deertick (Ixodes scapularis)
the tick vector for the bacterium that causes lyme disease (Borrelia burgdorferi)
What is yellow fever
disease caused by a virus spread through Aedes mosquitos
What is MRSA
Methicillin Resistant Staphylococcus aureus or Multi-drug Resistant S.A. It is a super-bug strain that has required immunity to many antibiotics including methicillin (a last resort drug)
Describe nosocomial infections
Nosocomial infections are infections acquired by hospital patients (also called Hospital acquired infections)
What are endemic diseases (Example)
Disease which is normal and regularly found in a given population at a predictable level
ex. influenza is endemic to canada
What are epidemic diseases (example)
disease occurrence at a higher than usual frequency in a given population in a short period of time
ex. Zika virus, ebola
What are pandemic diseases (examples)
A countrywide or worldwide epidemic
ex. 1918 flu pandemic, 2009 H1N1
What are sporadic diseases (examples)
A few scattered cases
ex. measles outbreak at disneyland
Describe four reservoirs of infections
A. Normal flora (opportunistic infections)
B. Human Carriers
C. Animal Reservoirs (Zoonosis)
D. Abiotic (Non- living sources)
Describe three ways (with examples) disease can spread via direct contact
- Shaking hands with someone who has the flu
- Kissing someone infected with Mono (infectious Mononucleosis)
- Sexual contact with someone infected with chlamydia
Describe three vehicles (with examples) that can transmit disease
- Waterborne- drinking water contaminated with feces or giardia
- Foodborne- eating undercooked chicken with salmonella
- Airborne- someone with a cold sneezes on your face
Describe two vectors (with examples) that can transmit disease
- Mechanical Vectors- a fly’s foot contaminated by feces lands on the hosts food and they eat it
- Biological Vectors- A kissing bug bites you and now you have Trypanosoma cruzi
What are nosocomial infections and how are they controlled?
Nosocomial infections are infections that are acquired in hospitals. They are controlled by hand hygiene, disinfecting surfaces, using gloves, infection control policies
