Positive stranded RNA viruses Flashcards
5+ stranded RNA viruses
Go to a toga party, drink a corona, dip your caleese in picorna sauce, and it’s flaviful.
Togavirus Coronavirus Caliciviridae Picornavirus Flaviviridae
Hepatitis C Virus
Chronic hepatitis IV drug users Jaundice, N/V, RUQ pain, dark urine 50% chronic HVC Ab for diagnosis and fatty liver, bile duct, lesions, lymphoid follicles
RNA positive stranded viruses
ss
Icosahedral capsid
No envelope: Hep A, Hep E, Polio, Coxsackie, Rhino, Noro
Corona has helical capsid
Hepatitis A Virus
Extremely stable not inactivated by autoclave
Fecal oral, shellfish
Epidemic outbreaks, endemic in Asia, Africa, Latin America
Asymptomatic in young
Mild sick at first
Third week dark urine, jaundice, scleral icterus, pale stool
No chronic infections
IgM Ab to HAV
Self limiting
Killed vaccines
Hepatitis E Virus
Waterborne transmission (flooding/raining season)
Asia, Africa, Latin America
Detected by PCR
Virus she’s for 2 weeks in feces
Mild acute hepatitis, usually asymptomatic
Mortality in pregnant women, increases with trimesters
Polio Virus
Canyon b/n proteins binding sites for polio receptor
Fecal oral, majority are asymptomatic, shedding occurs oral 3-5 days, feces for weeks
Into mouth then can spread to CNS, heart, liver
Systemic: ha, sore throat, fever, meningitis
Paralytic: spinal cord/brain stem leads to paralysis, damages anterior horn, muscle weakness
Post polio syndrome: surviving neurons reinnervated and will later deteriorate
Salk (injected vaccine): inactivated
Coxsackie Virus
Mouth is portal of entry
Coxsackie A: vesicular lesions of hand foot mouth
Coxsackie B: involve body, myocarditi/pleurodynia (devils grip)
Aseptic meningitis
Pleurodynia: very sudden abdominal/CP/fever
Myocarditis: fever, precordial pain, arrhythmia, heart failure (cardiomegaly from edema)
Viral proteases 2a cleaves host proteins like dystrophin
Supportive care
Rhino Virus
Exception to envelope rule Resp droplets Does not survive GI Antigenic drift Common cold: URI Attaches via ICAM-1 in canyon, replication mostly in nose, produce bradykinin and histamine -> rhinorrhea Transient immunity Nasal discharge, sneeze, cough, sore throat Self limiting
Rubella Virus
E1 and E2 for attachment and fusing
Seronegative pregnant woman most concern
Post natal: auricular lymphadenopathy, rash on face/neck/chest and moves down
Congenital: earlier infection worse outcome, cataracts, blueberry muffin rash, deafness, celery stalk long bones, cardiac defects, 50x risk DM
Supportive care, in pregnancy termination if IgM
Live attenuated vaccine
Alpha Virus
Mosquitoes, traveling
EEE/WEE/VEE
most asymptomatic
Arthritis, encephalitis, , fever, ha, chills, N/V, spastic paralysis, tremors
CNS normal glucose high protein, leukocyte in CSF (first is herpes)
Supportive care
Corona Virus
Resp droplets
Common cold, transient immunity, cells fuse to form sycytia (not in rhino)
Coryza, no sore throat or cough
SARS
Norovirus
Six pointed star Fecal oral, aerosolized vomit Profuse Vomiting, milder diarrhea Older children/adult, cruise Infects SI Short incubation O blood type is more susceptible No long lasting immunity Supportive care
Arbovirus
Insect vector
Aedes aegypti mosquito (day biting)
Gulf coast region
Dengue: primary liver spleen thymus Peyer’s, abrupt fever, retro-orbital eye pain, transient rash (scarlatininform), severe bone pain, n/v, lymphadenopathy
Secondary hemorrhagic, worse, rapid deterioration, scattered petechiae, ecchymoses, weak pulse, hypotension, GI bleeds
Yellow fever: hepatotropic (Kuppfer cells), fever, ha, backache, severe jaundice, GI bleeds, hypotension, black vomit
Live attenuated vaccine
St. Louis/Japanese encephalitis: Culex mosquito (night biter)
IgM, tigers, virus isolation
Supportive care, hemorrhagic not too much fluids
