Week 11 - Infectious Diseases Flashcards
What is a disease?
Pathological condition of body parts/tissues characterized by group of symptoms
What is an infectious disease?
Disease caused by infectious agent (bacterium, virus, fungus, etc.)
What is an infection?
Occurs when infectious agent enters body and begins to reproduce.
What is a pathogen?
An infectious agent that causes disease
What is a host?
An organism infected by another organism
What is virulence?
Relative ability of an agent to cause rapid/severe disease in a host
What is an epidemic?
Spread of an infectious disease beyond a local population
What is a pandemic?
Spread of an infectious disease to a world-wide scale
What are Koch’s Postulates for proving an agent causes a disease?
1 - Agent must be associated with every case of disease
2 - Agent must be isolated from a diseased host and grown in culture
3 - If Culture-grown agent is introduced to a healthy susceptible host, they must contract the same disease
4 - The same agent must again be isolated from the infected experimental host
What are common agents of diseases?
- Bacteria
- Viruses
- Protozoa
- Fungi
- Helminths(animals)
What are bacteria?
Oldest/most abundant life form. Single-celled, lack a nucleus.
What are viruses?
Small microbes consisting of mostly DNA/RNA. Are not cells and cannot carry out life on their own
What are protozoa?
Single-celled eukaryotes with nucleus.
More similar to human cells, do a bit of everything
What are the phases of an infectious disease?
1 - Incubation period - time between infection and appearance of signs and symptoms
2 - Prodromal phase - mild, nonspecific symptoms that signal onset of some disease
3 - Clinical phase - experience typical symptoms of disease
4 - Decline phase - symptoms subside
5 - Recovery phase - symptoms disappear and body regains strength
What makes a pandemic?
- Ease of transmittance
- Longer possible infection time