Micro- Viruses Flashcards
Live attenuated vaccines (6)
smallpox, yellow fever, chickenpox, Sabin poliovirus, MMR, Influenza (intranasal)
Killed vaccines (4)
Rabies, influenza (injected), salk polio, HAV
Recombinant vaccines (2)
HBV, HPV
What type of DNA do most DNA viruses have? What are exceptions?
All except parvoviridae are dsDNA
All are linear except papilloma, polyoma, hapadnaviruses (circular)
What type of RNA are most RNA viruses?
Most are ssRNA except reovirus (dsRNA)
Where do RNA and DNA viruses replicate?
DNA viruses- replicate in nucleus (except poxvirus)
RNA viruses- replicate in cytoplasm (except influenza, retroviruses)
What type of lymphadenopathy is common for EBV?
posterior cervical nodes
Associated with “owl eye” inclusions
CMV
Where in addition to the skin can HHV-8 affect?
lungs, GI tract
Where do CMV and EBV lay dormant?
CMV- mononuclear cells
EBV- B cells
High fevers for several days that can cause seizures followed by diffuse macular rash (exanthum subitum)
Roseola- HHV-6
What herpesviruses cause keratoconjunctivitis vs retinitis?
HSV-1: keratoconjunctivitis
CMV: retinitis
What does the tzanck test test for?
HSV-2
detect multinucleated giant cells
What cells cause intranuclear Cowdry A inclusions?
HSV
What are the picornaviruses? What type of infection do they cause and how are they transmitted?
PERCH Poliovirus Echovirus Rhinovirus Coxsackievirus HAV Can cause viral meningitis (exc HAV, rhino) Transmitted oral-fecal (exc rhinovirus)
What type of virus is rhinovirus? What distinguishes it from those in its class?
picornavirus
nonenveloped RNA virus
not acid labile
Causes high fever, black vomit, jaundice
yellow fever
What type of virus is yellow fever? What is its vector?
Flavivirus
Aedes mosquito
Causes villus destruction with atrophy, leads to decr absorption of Na+, loss of K+ (virus)
rotavirus
What type of virus is rotavirus?
segmented dsRNA
reovirus
What type of virus is influenza virus?
orthomyxovirus
enveloped, neg ssRNA, 8-segments
What do the surface proteins of influenza do?
Hemagglutinin- viral entry
Neuraminidase- progeny virion release
Causes fever, postauricular lymphadenopathy, arthralgias, fine rash
Rubella
Congenital infection causes “blueberry muffin appearance” What does this indicate?
rubella
extramedullary hematopoiesis
What is an important surface marker of paramyxoviruses? What does this do?
F (fusion) protein
causes respiratory epithelial cells to fuse and form multinucleated cells
What are the paramyxoviruses (4)
Parainfluenza (croup)
mumps
measles
RSV
Causes cough, coryza, conjunctivitis, koplic spots
measles
What are 2 dangerous sequelae of measles infection?
SSPE (subacute sclerosing panencephalitis)
giant cell pneumonia
Causes parotitis, orchitis, aseptic meningitis
Mumps
Negri bodies commonly found in purkinje cells of cerebellum and in hippocampal neurons
rabies
What type of virus is HCV?
flavivirus
enveloped, RNA ss+ linear, icosahedral
What type of virus is HBV?
hepadnavirus
What type of virus is HDV?
RNA delta virus
enveloped, ss - circualr
Compare superinfection vs coinfection of HDV and HBV?
Superinfection (HDV after HBV)- short incubation
co-infection (HDV with HBV)- long incubation
What type of heptatitis virus has particularly high mortality in pregnant women?
HEV
What type of virus is HEV
RNA hepevirus
nonenveloped ss+ linear icosahedral
Type of HBV infection:
HBsAg+, HBeAg+, Anti-HBc IgM
Acute HBV
Type of HBV infection:
Anti-HBe+, Anti-HBc IgM
Window period
Type of HBV infection:
HBsAg+, HBeAg+, IgG
chronic, high infectivity
Type of HBV infection:
Anti-HBs, Anti-HBe, IgG
recovery from HBV
What distinguishes high transmissibility vs low transmissibility for HBV?
High transmissibility: HBeAg
Low: Anti-HBe
How is AIDS diagnosed?
< 200 CD4 or AIDS-defining condition
What part of HIV can cross the placenta?
anti-gp120- casues fals positive ELISA/western
What are the HIV structural genes, what do they encode?
env - gp120 (attach do CD4), gp21 (fusion and entry)
gag0- capsid protein
pol- reverse transcriptase, aspartate protease, integrase
What are HIV coreceptors
CCR5- early
CXCR4- late
Causes low-grade fecers, cough, hepatosplenomegaly, tongue ulcers in AIDS
Histoplasma capsulatum (Oval yeast cells within macrophage)
Causes superficial vascular proliferation in AIDS patients
Bx shows neutrophilic inflammation
Bartonella henselae
Causes superficial vascular proliferation in AIDS patients
Bx shows lymphocytic inflammation
HHV8- kaposi sarcoma
Causes interstitial pneumonia in AiDS patients
CMV
When should MAC be suspected in HIV pt?
CD4 <50, Tb-like disease
Where is Hairy leukoplakia likely found? what causes it?
lateral tongue
EBV
What CD4 count corresponds with oral and esophageal candida?
oral- CD4 <100
