Infectious Disease

Question 1

Why can Influenza spread so easily

Answer 1

Surface antigens are able to undergo periodic shift, preventing permanent immunization. Antigenic drift when changes are minor and antigenic shift when major

Pt are contagious 1 day prior to symptoms and 1 week after resolution

Question 2

Who is at risk fro severe influenza or influenza related complications

Answer 2

Age <2 and >65
Pregnancy or 2 weeks post partum
Morbid obesity
Indigenous ethnicity
Chronic care facility residents
Immunosuppression
Chronic conditions (heart, lung, renal, haem, endocrine, neuro)
Mod - severe development delay or intellectual disability

Complications
Bacterial pneumonia (commonly S Aureus)
Sinusitis and OM
Exacerbation of underlying disease
Rapidly progressing pneumonic causing ARDS

Question 3

Who qualifies for antivirals and what do they do

Answer 3

Neuraminidase inhibitors like Oseltamivir can reduce symptoms by 16.8hrs if commenced within 48hrs of symptoms. May decrease complications and severity but this is controversial UNLESS pt is hospitalized in which case it reduced mortality

To be given to pts hospitalized with severe disease or are high risk for complications