Influenza Flashcards
(10 cards)
Pathophysiology
Spread: droplet
Incubation: 1-4d
Infectivity: 1d before symptoms start to 7d after
Immunity: only strains which have already attacked pt
Presentation
Fever Headache Malaise Myalgia N/v Conjunctivitis
Complications
Bronchitis Pneumonia: esp. Staph Sinusitis Encephalitis Pericarditis Reyes: rash, vomiting, ↑LFTs in children give aspirin
Ix
Bloods: lymphopenia,
thrombocytopenia
Culture: 1wk from nasal swabs
PCR: takes 36h
Mx
Bed rest + paracetamol
If severe:
- ITU
- Cipro and co-amoxiclav: prevent Staph and Strep
- Oseltamivir
- Neuraminidase inhibitor
Zanamivir:
Inhaled NA inhibitor active
Prevention
Good hygiene
Trivalent Vaccine
Who is offered the flu vaccine
> 65yrs
DM, COPD, heart, renal, liver failure
Immunosuppression: splenectomy, steroids
Medical staff
Haemagglutinin
Surface antigen which binds to cells of infected person
Neuraminidase
Surface antigen that releases the virus from the host cells
Genetic variance
Life cycle 6 hrs
High error rate as no viral RNA polymerases
Causes antigenic drift