-ve RNA Viruses Flashcards
Measles
Causes 4c “cough , coryza , conjuctivits , koplick spots
Measles complications
- pneumonia
2. SSPE “subacute sclresonig pan-encephalitis “
Measles virulence factors
HA , fusion protein
Reduce measles mortality
Vitamin A
Mumps sings and symptoms
Parotitis , orchitis , meningitis
Mumps virulence factors
HA , fusion protein , NA
Live attenuated MMR vaccine
Contraindicated in pregnancy
Rash of measles
Start on the face and spread downwards
RSV mechanism of infection
Attach to G protein
The most common cause of bronchiolitis and pneumonia in infants
RSV
RSV virulence factor
Fusion protein
Treatment of RSV
Ribavirin
Prevention of RSV
Palivizumab
Parainfluenza symptoms and signs
Seal bark cough , steeple sign on x-ray , croup”laryngotracheobrochitis” , inspiratory stridor .
Parainfiluenzae virus virulence factors
HA , fusion protein , NA
Bonya virus is
Enveloped “ obtained from the Golgi body of host cells
Bonya virus has
3 circular segments
Bonya viruses species
Arbovirus , Hantavirus, California encephalitis virus , Rift Valley fever virus
Hantavirus reservoir
Deer mouse
Hantavirus transmitted by
Rodent urine/feces
Hantavirus cause
Pulmonary Edema
Prerenal azotemia
Hemorrhagic fever
California encephalitis virus , Rift Valley fever virus transmitted by
Aedes mosquito
Arenavirus characters
Enveloped -ve sense RNA
Ambisene
Heclical
Has 2 segments
Virus has garnular appearance on microscopy is
Arenavirus
Arenavirus transmission by
Rodents
LCV lymphocytic choriomeningitis virus is a member of
Arenavirus
LCV cause
Meningoencephalitis
Fever
Arenavirus inactivated by
Heat
Irradiation
Reovirus is
Naked double stranded RNA virus
The segmented viruses are
BOAR “ Bonya , Orthomyxo , Arena , Reo” viruses
Reovirus has ………….. segments
11
Rotavirus is a member of
Reovirus family
Rotavirus cause
Watery diarrhea by NSP4 toxin
NSP4 toxin increase
Chloride permeability
………….. are at risk for rotavirus infection
Children
The number one cause of severe diarrhea in young children is
Rotavirus
Colorado tick virus is a member of
Reovirus family
Colorado tick virus cause
Fever , myalgia , vomiting
Rotavirus oral live attenuated vaccine side effect is
Intussusception (telescoping of the bowel)
All RNA viruses replicate inside
The cytoplasm except orthomyxovirus (inside the nucleus)
Orthomyxoviruses include
Infeluenza A , B and C
Orthomyxovirus has ………… segments , which allow for ………….
8 , antigenic variation
………………. is point mutation in the viral genome of orthomyxovirus
Antigenic drift
…………………. is when segments are shared to form a new species
Antigenic shift
Antigenic shift responsible for
Pandemics
Antigenic drift responsible for
Seasonal flu or epidemics
influenza viruses – A causes……………………..
– B causes…………………
epidemics and pandemics (Antigenic shift), epidemics (antigenic drift)
Orthomyxovirus pathogenesis by
Hemagluttinin and neuroaminidase
Hemagluttinin bind to
sialic acid promoting viral entry
Neuroaminidase cleaves
sialic acid to release virions from host cell (promotes progeny virion release)
HA molecule will bind to sialic acid on the cell membrane, then endocytosed into the cell, pH needs to be changed by ………………. to allow for uncoating.
M2 protein
M2 protein inhibitors
Amantadine/Rimantadine (no uncoating)
Neuroaminidase inhibitors
Oseltamivir/Anamivir (inhibit virion release)
Infeluenza transmission via
Respiratory droplets
Infeluenza has two vaccines
Injectable killed and intranasal live attenuated
A major complication for infeluenza
Pneumonia
…………… is contraindicated in children with viral illness
Aspirin cause Reye syndrome ( encephalitis and hepatomegaly )
Infeluenza associated with
Guillain-Barré syndrome (ascending paralysis)
Filovirus is
Enveloped helical -ve sense RNA virus
Viruses of Filovirus family
Ebola and Marburg viruses
Filoviruses can cause
Fever , Petechial rash can progress to hemorrhagic fever , end-organ failure and shock
Filovirus transmission
Through infected bats or primates (monkeys)
Bullet shapd virus is
Rhabdovirus
Carriers of rabies
Bats ,Foxes skunks and other rodents
Rhabdovirus pathogenesis
binds by its glycoprotein spikes to nicotinic acetylcholine
receptors in postsynaptic membrane of motor endplate
Rabies symptoms
Fever , encephalitis , hydrophobia
Rabies diagnosis
Negri bodies (eosinophillic cytoplasmic inclusions ) found in hippocampal pyramidal cells and purkinje cells of cerebellum.
Rabies treatment
Postexposure prophylaxis is wound cleaning plus immunization with killed vaccine and rabies immunoglobulin