Orthomyxoviruses Flashcards
(49 cards)
What shape are orthomyxoviruses?
Pleomorphic
Symptoms of Orthomyxo?
Febrile illness of upper and lower respiratory tract
Sudden onset of fever, cough, soreness, malaise, etc.
Most common serious complication of orthomyxo?
Pneumonia
Types of Influenza?
A, B, and C
Describe Influenza Type A
Most virulent human pathogen
Infect many animal species
Wild aquatic birds are a natural reservoir
Describe Influenza Type B
Milder than Type A
Only Humans
Mostly milder, mutate slowly
Describe Influenza Type C
No epidemics
Rarely causes disease
Nobody really cares…
What is an influenza proton pump called?
M2
What is M2 used for?
Uncoating
Describe the influenza genome?
-ssRNA, 8 segments
Influenza caspid? Envelope?
Helical
Yes
Where does influenza replicate?
The nucleus
Why does influenza rep. in the nucleus?
To hijack protons used to add the protective RNA cap
How does influenza enter a cell?
Binding of hemaaglutinin to cell surface
What targets neurominidase?
Tamiflu
Components of ribosomal RNA?
PA, PB1, PB2
Typical clinical manifestation of influenza?
Fever, Sore throat, myalgia, headache
Ocular symptoms (photophobia, tears, ache)
Weakness, fatigue, cough, GI probs
Two influenza complications…
Primary influenza pneumonia and secondary bacterial pneumonia
Describe primary influenza pneumonia.
Progressive cough, dypnea, and cyanosis
Infiltrative patterns without consolidation on radiograph
Who is at risk for primary influenza pneumonia?
3rd trimester women
elderly patients
Causes of secondary bacterial pneumonia?
Staph Aureus
Strep pneumoniae
Haemophilus influenza
What is the most serious complication of secondary bacterial pneumonia?
Staphylococcal pneumonia
Symptoms of staphylococcal pneumonia?
Severely ill
Hypoxemia, Elevated WBC, productive bloody cough, cavitary infiltrates on radiograph
Potential non-pulmonary complications of influenza?
Myositis
Cardiac Complications
Reye’s syndrome
Encephalitis
