Schein - - Strand RNA Viruses Part 2 Flashcards
What is particularly unique about the envelope of the paramyxoviruses?
They have an additional spike - the F SPIKE
Paramyxovirus morphology
The envelope is spherical
Has HA, N, and F glycoproteins spikes
Nucleocapsid is Helical
Non-segmented genome
What does the F glycoproteins do?
Allows for fusion of the virus with the host cell membrane. Rather than doing receptor mediated endocytosis, it just fuses.
Is paramyxovirus segmented or non-segmented?
Non-segmented
What viruses are associated with Syncytia? What are Syncytia?
Paramyxoviruses
- Syncytia are multinucleated giant cells that may fuse many infected cells together. They use the F SPIKE to do this.
Parainfluenza
Paramyxovirus
- causes the croup cough in infants and children. Also causes LRT tract infections.
- uses HA, N, and F glycoproteins
(Mnemonic - if you remember the mnemonic with “in flu enza” the bird, you’ll remember that parainfluenza causes croup because croup sounds like coop)
Mumps
Replicates in the salivary gland and causes massive swelling and inflammation in that area.
- it is spread by respiratory secretions and primarily affects the URT.
- can cause viremia and spread to other organs.
- Could cause CNS issues, orchitis, or breast enlargement
- could cause kidney, heart, or pancreas issues
- has HA, N, and F glycoproteins
Treatment/prevention of Mumps
MMR - live attenuated vaccine
Hyper immune glob in
Measles
Primary infection of the respiratory tract
- you will see “Koplik’s spots” which are red spots by the molars in the mouth
- causes viremia so there will be widespread systemic involvement
- you will see a maculopapular rash that starts at the head and moves downward.
- secondary bacterial infections are common due to the damaged cilia.
- punctuate keratitis - inflammation lesions on the cornea
- can cause SSPE (subacute sclerosing panencephalitis) - a CNS disease about 10 years after having measles
- encephalomyelitis
- giant cell pneumonia
- HA and F glycoproteins
Respiratory Syncytial Virus
Common cause of viral lower respiratory tract disease in infants and children.
- No HA, N activity
- treat with ribavarin, RSV antibodies, Palivizumab (monoclonal antibodies)
Rhabdoviridae causes what disease?
Rabies virus
Shape of rabies virus
Bullet shaped
What unique glycoprotein spike does Rabies virus/rhabdoviridae have?
G
Morphology of rhabdoviridae / rabies virus
Bullet shaped
Helical nucleocapsid
Unsegmented RNA
G glycoprotein spike
Rabies clinical phases
Prodromal - initially there are just flu-like symptoms due to the increase in interferon
Acute neurological - nervous system dysfunction
Coma - death due to respiratory arrest
