week 5 Flashcards
What two factors are needed for an infection to occur?
A host and an organism
Define infection:
an invasion of a host caused by a pathogen
What are 4 different kinds of infections that can occur?
Bacterial, viral, fungal, parasitic
What is one of the most common and deadly bacterial infections today?
MRSA-caused by staph aureus
Bacteremia/speticemia is used to describe:
a systemic bacterial infection, in which bacteria is found in the blood
What is a common cause of bacteremia?
E.coli
What are 3 examples of infections caused by viruses?
H1N1, HIV, the flu
Why are viral infections difficult to treat?
They do not follow a normal organism growth pattern, they are abnormally shaped, and have no nucleus just reverse transcriptase
Viruses are protected by several layers of ____________.
proteins
What are three examples of fungal infections?
candida (yeast), PCP, aspergillus
What are two examples of parasitic infections?
giardiasis, trichinosis
List the steps in the chain of transmission?
Infectious agent, susceptible host, portal of entry, mode of transmission, portal of exit, reservoir
T or F: The chain of transmission cannot be broken.
FALSE.
List three ways we can break the chain of transmission:
handwashing, education, @ portal of entry: proper wound care
Under normal circumstances inflammation can result in:
increasing healing, decreasing infection
T or F: Inflammation can result from infection.
TRUE
T or F: Infection can result from inflammation.
FALSE- inflammation will not cause infection, inflammation is always in response to an infection
Define hypersensitivity:
an altered immunologic response to an antigen resulting in disease or damage to the host
How does hypersensitivity develop?
a pathologic immune response develops after one or multiple exposures to an antigen
What is an allergy?
an exaggerated response to the environment
What is autoimmunity?
intolerance to self-antigens, does not recognize self as self
Define alloimmunity:
occurs when the immune system of on individual produces an immunologic response against tissues of another individual during transfusions, transplanted tissue, or a fetus during pregnancy
List the 4 mechanisms of hypersensitivity:
Type 1: IgE (allergies), Type 2: Tissue-specific, Type 3: Immune-complex, Type 4: Cell-mediated
What is happeneing during a Type I response?
histamine overreaction
What is an example of an allergic (IgE) response?
Seasonal rhinitis
What is happening during a Type II response?
destruction of cells due to antigen on membrane
What is an example of a Type II: Tissue Specific reaction?
Graves disease
What is happening during a type III response?
antigen-antibody complexes are deposited on vessels or tissues
What is an example of a Type III:Immune-complex reaction?
systemic lupus erythematosus
What is happening during a Type IV resonse?
T-cells are over sensitized and react to the enviroment
What is an example of a Type IV:cell-mediated reaction?
contact sensitivity to metals (jewelry) or poison ivy
What is the most rapid and severe immediatee hypersensitivity reaction?
anaphylaxis
Wht two types of immunodeficiencies exist?
congenital and aquired
What is an example of a congenital immunodeficiency?
agama globulin anemia
What is an example of an aquired immunodeficiency?
AIDS
T or F: HIV and AIDS are the same thing, and the terms can be used interchangeably
FALSE. An HIV infection can lead to AIDS, but they are NOT the same thing
T or F: Drugs can successfully counteract the HIV virus when it is inside human cells.
FALSE
What is the ultimate goal of HIV medications?
To control the disease, not cure it
What are CD4 cells?
Helper T and B cells
A person is considered to have AIDS when what conditions are met?
HIV infection + CD4 <200
What are opportunistic diseases?
Will take over the host when they get the opportunity, for example, when a person becomes immunocompromised
What is an example of an opportunistic disease?
HIV-can live in a host for years and can turn into an AIDS infection if the host becomes immunocompromised
What happens during the acute phase of an HIV infection?
lympadenopathy, fevers, fatigue, malaise, joint pain, weight loss, muscle wasting
What is happening during the dormant phase of an HIV infection?
A patient will have no symptoms, but the virus is present in their system
What is the final stage of an HIV infection?
AIDS
How is HIV transmitted?
through blood and bodily fluids
