Respiratory Viruses Flashcards
What pathologic viruses belong to the paramyxovirus family?
Parainfluenza
RSV
Measles/Rubeola
Mumps
What disease is caused by parainfluenza virus?
Croup
What disease is caused by RSV?
Bronchiolitis in babies
What paramyxovirus is associated with pulses paradoxus?
Parainfluenza secondary to upper airway obstruction
Describe croup.
Barking cough
Inspiratory stridor
What effect can croup have on blood pH?
Respiratory acidosis
Obstruction of airway
Inspiratory stridor is not only due to croup. For instance it could be due to foreign body aspiration. What other infectious disease is commonly associated with inspiratory stridor and what is the MC causative organism?
Epiglottitis- H. influenzae
What is the classic finding on anterior x-ray of neck in a child with croup?
Steeple sign- mucosal edema
What is the treatment for croup?
Dexamethasone
Nebulized epinepherine
Cold humidifier
Detail the symptoms of measles.
Cough
Conjunctivitis
Coryza (runny nose)
What are the dermatologic findings of measles?
Koplik spots- bright red spots, white center on buccal mucosa
Maculopapular rash
(Kolpik spots precede rash)
A child presents with Measles. A lymph node biopsy is taken. What do you expect to see?
Warthin-Finkeldey multinucleated giant cells
What vitamin reduces morbidity and mortality of measles?
Vitamin A
What are possible sequela of measles infection?
Encephalitis
Subacute sclerosing panencephalitis
Giant cell pneumonia
What are the symptoms of mumps infection?
Parotitis
Orchitis
Meningitis
Pancreatitis
How can you diagnose RSV?
Nasopharyngeal wash
Detect antigen
Detail the genome structure of coronaviruses.
SS
+
RNA
Linear
Detail the genome structure of paramyxoviruses.
RNA
Linear
Do coronaviruses have an envelope?
Yes
Do paramyxoviruses have an envelope?
Yes
Detail the capsid symmetry of coronaviruses.
Helical
Detail the capsid symmetry of paramyxoviruses.
Helical
What viral family do MERS and SARS belong to?
Coronaviruses
All paramyxoviruses contain F protein. What is the effect of F protein?
Causes fusion of epithelial cells to form multinucleated giant cells
What monoclonal antibody can be given to premature infants to prevent pneumonia caused by RSV?
Palivizumab
What viral family do influenza viruses belong to?
Orthomyxoviruses
Do influenza viruses have an envelope?
Yes
Detail the structure of the influenza genome.
Linear
8 segments
Detail the capsid symmetry of orthomyxoviruses.
Helical
All RNA viruses replicate in the cytosol except, however, there are 2 exceptions. What are these exceptions?
Influenza Retrovirus
Patients who contract influenza viruses are at risk of fatal bacterial superinfection. What are the most common organisms responsible for bacterial superinfection?
S. aureus
S. pneumoniae
H. influenzae
Contrast the cause of genetic shift with genetic drift.
Shift is due to reassortment of viral genome segments.
Shift causes pandemics.
Shift is more deadly than drift.
Shift occurs in influenza A.
Drift is due to random mutations in hemagglutinin or neuraminidase.
Detail the function of hemagglutinin and neuraminidase.
Hemagglutinin- promotes viral entry
Neuraminidase- promotes progeny virion release
What is the most common cause of the common cold?
Rhinovirus
How many major antigenic sub-types are there of neuraminidase and hemagglutinin?
NA- 9
HA- 13
What influenza type can infect many animal species?
A
What influenza types do we vaccinate against?
A
B
What is the leading cause of death due to influenza?
Secondary bacterial infection (pneumonia)
What drugs are used as neuraminidase inhibitors?
Zanamivir
Oseltamivir
What drugs are no longer used to treat influenza due to resistance?
Amantadine
Rimantadine
Although amantadine is no longer used to treat influenza it is still useful to treat what condition?
Parkinson disease- increased dopamine release and inhibits uptake
What is the receptor for measles virus?
CD46- complement receptor
allows for disseminated infection of Measles virus
What is the most common cause of bronchiolitis and pneumonia in those under 1 year of age?
RSV