- RNA Viruses Flashcards
- RNA virus families (6)
- Orthomyxoviridae
- Paramyxoviridae
- Rhabdoviridae
- Arenaviridae
- Bunyaviridae
- Filoviridae
Double Stranded RNA viruses (1)
Reoviridae (REO viruses- Rotavirus)
- Influenza virus characteristics
- helical nucleocapsids
- multiple segments (influenza = 8)
- M2 protein causes drop in pH, allowing exit from capsid after endocytosed
- Replicates in NUCLEUS (unlike other RNA viruses)
- Respiratory spread, can cause secondary viremia
Reyes Syndrome
acute brain damage, liver dysfuntion
-result of aspirin use post influenza (or other viral) infection
Antigenic Shift
mechanism of new influenza (combines with other segments of another coinfected influenza) causing pandemics
-only occurs in influenza A
Anti-influenza drugs (4- classes, uses)
Oseltamivir + Zenamavir/Peramivir: neuraminidase inhibitors. Can use for prophylactic/infection, influenza A/B
Amantidine/Rimantidine: uncoating agents. Vs. influenza A only
Paramyxoviridae (6)
- Parainfluenza virus
- Mumps
- Measles
- RSV
- hMPV
- Nipah/Hydra
Paramyxoviridae features (morphology, segments, distinct proteins)
- Enveloped, helical capsid, non-segmented
- Uses F (fusion) proteins in addition to NE and HA
- F allow syncytia formation (multinucleated giant cells), inclusion bodies
Parainfluenza virus (infection, spread, symptoms)
Paramyxoviridae
- LRT infections and CROUPE in infants/children
- severe: brochiolitis, pneumonia in elderly/immunocompromised
- like other paramyxoviridae, respiratory spread
Mumps (class, infection, symptoms)
Paramyxoviridae
- URT, can spread to blood. Replicates in parotid, swelling. Can cause unilateral painful breast, testicle swelling too (also others- kidney, heart, pancreas, CNS, deafness, fetal complications)
- treat with MMR vaccine
Measles (infection, symptoms)
Paramyxoviridae
- lives on fomites, major killer in developing countries
- No NE, unlike other paramyxoviridiae
- Spread by respiratory droplets
- Starts Koplik’s Spots (inner cheek), viremia causes macropapular rash (face–>body)
- Complications: secondary bacterial infections, keratitis, subacute sclerosing panencephalitis, giant cell pneumonia
Respiratory Syncytial virus (RSV) (symptoms, treatment
- Paramyxoviridae
- No HE/NA
- most common LRT in infants/children
- treat with ribavirin, Ig (palivizumab)
Rabies (morphology, symptoms (early/late), diagnostic inclusion
Rhabdoviridae
- bullet-shaped, helical capsid, unsegmented
- Prodromal (early): flu-like
- Acute Neurological (mid): weeks later, virus reaches CNS, spasms, paralysis, agitation, coma, death (from respiratory paralysis)
- Negri Bodies diagnostic in nerve cells
- treat with vaccine/Ig
Arenaviruses (morphology, host, exs (4))
Arenaviridae
- Bisegmented, ambisense RNA (transcribe from + AND - strands)
- GP1/2 proteins, 1 = neutralizing antibody vs. cell membrane receptors, 2 like M2 (pH acidification to leave capsid in cytoplasm)
- rodent host, spread by inhale/contact/ingestion
- Include LCMV (lymphocytic choriomeningitis virus), Lassa Fever, Hemorrhagic Fevers (Junin, Machupo)
- treat with ribavirin
Bunyaviridae (characteristics, spread, viruses (5) and symptoms)
- 3 RNA segments
- also arboviruses (arthropod host, rodent)
- Cause La Crosse virus (CNS, meningitis, encephalitis), Hantaan virus (pulmonary/hemorrhagic disease), Crimean-Congo Hemorrhagic Fever virus (hemmorhagic), Sin Nombre virus (cardiac/pulmonary), Heartland Virus (midwest, GU/systemic/flu, ixodes tick)
