UMEM Educational Pearls

Category: Critical Care

Title: Influenza 2014-What you need to know

Keywords: influenza, tamiflu, (PubMed Search)

Posted: 12/16/2014 by Feras Khan, MD
Click here to contact Feras Khan, MD

How does it present?

Fever, cough, sore throat, runny nose, muscle aches, headaches, fatigue, diarrhea (in children especially)

Who cares…I got my vaccine! Does the vaccine work this year?

There has been some antigenic drift this year in the influenza A (H3N2) type virus.
52% are anti-genically different than the H3N2 vaccine virus.
So the vaccine is less effective this year but it can give some cross-protection (in addition to protection against the other strains used in the vaccine)
CDC recommends still getting the vaccine (http://www.cdc.gov/flu/protect/vaccine/vaccines.htm)
91% of samples reported to the CDC have been influenza A this year

Can I test for this?

The CDC is recommending treatment...wait I thought we were done with Tamiflu?

Benefits: shortens the duration of symptoms (day or less), reduces the risk of complications, reduces the risk of death among hospitalized patients
Risks: side effects (see below)
A recent Cochrane review revealed that treatment did not really help reduce complications and most of the data on anti-viral agents is biased (Roche funded) and hotly debated

Who is at risk/who deserves consideration for treatment?

Pearls of treatment

Treat as early as possible (<48hours from symptom onset)
5 days of treatment; twice daily dosing. Wt based for children. Renally dosed.
Oseltamivir: used for more severe influenza cases
Zanamivir: 7 years or older; IV Zanamivir is currently in Phase III clinical trials

What are the side effects of anti-viral agents?

http://www.cdc.gov/flu/index.htm

2014 Apr 10;4:CD008965. doi: 10.1002/14651858.CD008965.pub4.