Lecture #13 Flashcards
What is a sporadic occurrence of disease?
Disease that occurs occasionally
What is an example of a sporadic occurrence of disease?
Hamburger Disease (E.coli found in hamburger, people buy, it’s recalled)
What is a endemic occurrence of disease?
Low and constant levels of a disease
What is an example of a endemic disease?
Common cold, malaria
What is a epidemic occurrence of a disease?
A disease that occurs in high numbers over a short period of time
What is an example of a epidemic disease?
Influenza
What is a pandemic occurrence of a disease?
Epidemic disease that occurs worldwide
What is an example of a pandemic?
Influenza, bird flu
What is emerging infectious disease?
New identified disease (notable number of cases)
What is an example of an emerging infectious disease?
West nile, MERS
What is a reservoir in regards to spread of infections? Give examples
Source of the infectious agent
ex. Object, food, living things, water, etc
What is a human reservoir in regards to spread of infections?
People who can harbour pathogens and transmit them to others
When can germs be transmitted during disease?
Any stage (incubation, prodromal, period of illness, convalescence or period of decline)
What are carriers in regards to the spread of infection?
People who can transmit pathogens without having any signs of the disease themselves
What is an example in history of a carrier of a disease?
Typhoid Mary- transmitting salmonella typhi
What is a zoonosis animal reservoir?
A disease that occurs in animals but can be transmitted to humans
What are some examples of a zoonosis reservoir?
- Influenza in bird and pigs
- Rabies in bats, skunks, etc
- Lyme disease in field mice transmitted by ticks
What are non living reservoirs?
Things that can be a source of an infectious agent that is not living (Soil and water)
What is an example of an infectious agent found in non living reservoirs? What does it do to humans?
Clostridium tetani found in soil that can lead to tetanus in humans when the bacteria enters the body through a cut
What are fomites? What are examples?
Any nonliving object that spreads pathogens
Ex. used kleenex, used syringes
What are the 3 main routes of transmission of a disease?
- Contact transmission
- Vehicle transmission
- Vector transmission
What are 3 types of contact transmission of disease?
- Direct- person to person (chlamydia or STI’s)
- Indirect- through fomites
- Droplets- spread by a short distance (less than 1 meter, sneezing, coughing, etc)
What is a vehicle transmission of disease?
A pathogen transmitted by a medium
What are 3 types of vehicle transmission? Explain each
- Waterborne- E.coli in water due to improperly treated sewage
- Airborne- spread over less than one meter
- Foodborne- food poisoning
What is a type of airborne vehicle transmitter disease?
Mycobacterium tuberculosis
What is an example of food borne vehicle transmitted disease?
Bacillus cereus and salmonellosis
What is vector transmission?
Animals that carry pathogens from one host to another
With the West Nile virus, what would be the reservoir, host and vector?
Reservoir- Birds
Vector- Mosquitos
Host- Humans
For lyme disease, what would be the reservoir, host and vector?
Reservoir- Field mice
Vector- Ticks
Host- Humans
What are Nosocomial Infections?
Hospital acquired infections
What are 3 ways that nosocomial infections can occur?
- Pathogens in the hospital
- Immunocompromised state of patients
- Chain of transmission
What are the 3 ‘chains of transmission’ that nosocomial infections can occur?
- Direct contact- staff to patient or patient to patient
- Indirect contact- through fomites
- Airborne- through ventilation systems
What are 4 ways of controlling spread of disease?
- Hygiene
- Vectors
- Avoidance
- Isolation
What are the ways that hygiene can prevent he spread of disease?
Proper: hand washing, sterilization, sanitation, prep of food and water and sanitization of sewage treatment
How can we control the spread of disease via vectors?
- Controlling insect vectors (Mosquitos that spread west nile
- Vaccination of domestic animals (against rabies)
How can we control the spread of disease with avoidance? Give examples
Avoiding contact with carriers
ex. wearing latex gloves
What does quarantine mean? What disease would cause a person to be put in quarantine?
Removal of infected individual from society
Ex. Tuberculosis Sanatorium
What is isolation in regards to controlling the spread of disease? What is an example of someone who would be put in isolation?
A person highly susceptible to a particular disease are put in isolation.
Ex. Bone Marrow transplant patients
