Viral Pathogenesis Flashcards
Tropism
a given virus is likely to infect certain tissues and not others. Enterotropic viruses = replicate in gut, etc.
Transmission and shedding
release of infectious particles from an infected host.
Local infections, sheeding occurs from the site of initial infection.
Enveloped viruses are fragile and often transmitted via close contact.
Non-enveloped viruses are hardies, can sustain lots and often associated via objects, respiratory or fecal routes
MOST transmission is horizontal,but vertical (parent/child) happens tooo!
Acute virAcute local viral infection
usually infections of epithelial cells at body surface (gut, resp. tract, eyes) short incubation time, include virus which includes MANY serotypes. Short lived immunity (IgA) Reinfections are common.
eg. colds, diarrheals diseases
Acute systemic viral infection
primary infection is in epithelium, viremia and systemic infection can result in secondary replicaton at various sites.
Lifelong immunity w/ both secretory IgA and serum IgG.
Measles and smallpox.
Chronic persistent viral infection
usually refers to virus infections that continue to produce new virus over long period of time.
Rubella in neonates
Chrinic latent viral infection
refers to virus infection in which virus genome is silent, little to no disease…. RETAIN ABILITY TO REACTIVATE!
VZV in nerves
Chronic slow viral infection
no symptoms on initial infection, long incubation period, may or may not induce immune response, eventual disease is followed by progressive deterioration and death :(
AIDS, cancer
Transforming Viral infections
retrovirus integrate into the host genome and activate viral/host oncogenes - some may cause DNA breakage. Some may cause ongoing inflammation -> contribute to tumorgenesis
