Infectious Disease Serology and Molecular Diagnostics Introduction Flashcards
Human microbiome helps protect against disease causing bacteria which aids in…
(1) Digestion; (2) Vitamin production; (3) Helps stimulate innate and adaptive immune systems.
Define infectious disease.
A microbe that damages host cells and/or alters physiology that results in clinical signs and symptoms of disease.
Define indigenous microbiota.
Normal flora; symbiotic microorganisms that reside on and colonize surfaces in an individual.
Define infectivity.
An organism’s ability to establish an infection.
Define pathogenicity.
Ability of an organisms to cause disease.
Define virulence.
A quantitative trait referring to the extent of pathology causing an infection of the host.
Define virulence factors.
Characteristics of microorganisms that can increase pathogenicity by contributing to its ability to establish itself in the host, invade host tissue or evade host immune responses.
What are four virulence factors that is contained within bacteria?
(1) Endotoxin - stimulates cytokine release;
(2) Pili/Flagella - adherence to host cells;
(3) Capsule - blocks phagocytosis, antibody attachment;
(4) Exotoxins - toxic proteins.
What are the three main mechanisms used during bacterial evasion?
(1) Avoiding antibodies; (2) blocking phagocytosis; (3) block complement.
What are the common methods used for lab diagnosis of bacterial infections?
Cultures, gram stains, antigen detection, molecular methods, and serological methods.
Methods used for detection of bacterial antigens.
Rapid testing by ELISA, lateral flow assay (LFA), or latex agglutination (LA).
Molecular methods used for bacterial antigens.
PCR testing.
Serological methods can diagnose infections when clinical symptoms are ___.
nonspecific.
What immunoglobulin is used to test for current infection?
IgM.
What immunoglobulins can be used to test for past exposure?
IgG.
