Influenza Flashcards
What are the 4 subtypes of Influenza? What types commonly cause illness in humans?
A/B/C/D
-Only A & B commonly cause illness in humans.
Influenza incubation period
24 – 96 hours
Severe illness and death from Influenza are highest in what demographics?
-people ≥65 years
-children <2 years
-people with underlying medical conditions
Flu Epidemics usually occur at what parts of the year?
fall and winter months
Adults shed the virus in the upper respiratory tract and are infectious for what time period?
1 day prior to symptom onset to 5–7 days after symptom onset.
Infectiousness is highest within how many days of onset & correlated
with fever?
3 days
Children & immunocompromised/severely ill may shed virus for how many days after the onset of symptoms?
> 10
What are the 2 distinct glycoproteins surrounding the viral membrane
(a) Hemagglutinin (eg. H1, H2, H3,..), x 18 subtypes
(b) Neuraminidase (eg. N1, N2..) x 11 subtypes
What does this define
Surrounding the viral membrane there are 2 distinct glycoproteins which is necessary for viruses to enter cells and are also how influenza undergoes periodic changes.
Virion structure
How are Influenza virus strains identified?
by the way the glycoproteins mix
What issue?
(a) Constitutional symptoms
-1) Fever/chills (> 100.8 F), myalgias, headache, malaise, occasional nausea, sometimes vomiting
(b) Influenza specific symptoms
-1) Nonproductive cough, sore throat, rhinitis, substernal soreness, nasal congestion.
(c) Physical findings:
-1) Predominantly localized to the respiratory tract; include nasal discharge, pharyngeal inflammation without exudates, and occasionally rales on chest auscultation.
Uncomplicated influenza illness
True/False
During flu season, a rapid influenza test is usually not necessary with a patient who is symptomatic.
True
- Influenza typically resolves within ____ days with an excellent prognosis in previously healthy adults, even without antiviral medication.
- However, cough and malaise can persist for ______ in
some cases.
- 1-7
- > 2 weeks
What is the treatment goal for the flu?
alleviate & control symptoms while preventing spread to other personnel.
Influenza – Treatment
Oseltamivir 75mg PO BID x 5 days if within 48 hours of onset
(a) Bed rest, oral hydration, analgesics /antipyretics, and
antitussives.
(b) Attempt to isolate the patient to the best of your ability while
underway.
(c) While in-port, the patient should remain at home until
symptoms improve.
(d) Influenza may put patient at risk for bacterial infection.
Antiviral treatment can be considered for any previously healthy patient with confirmed or suspected influenza within how long of
symptom onset.
48hrs
Influenza lab results
CBC: ________
UA: ________
CBC: WBC are usually normal or low early in infection.
UA: may be positive for protein.
What is the antiviral treatment for flu
Oseltamivir 75mg PO BID x 5 days. if within 48 hours of onset
True/False
Flu
Administer Oseltamivir as soon as possible to patient at high risk of complications even if > 48hrs has elapsed.
True
