MISC Qualitative Tests - Influenza Flashcards
What is the definition of influenza?
- Highly contagious, acute, viral infection of the respiratory tract
- Communicable disease that is easily transmitted through coughing and sneezing of aerosolized droplets containing live virus
What does influenza cause?
Annual cold weather outbreaks of acute febrile upper and lower respiratory tract illness with characteristic accompanying systemic features
Of the first two influenza types, which is the most common?
Influenza A
When is influenza best diagnosed?
During the first 2-3 days
What are the symptoms of influenza?
- Fever/feeling feverish
- Cough
- Sore throat
- Runny/stuffy nose
- Muscle/body aches
- HA
- Fatigue
- Vomiting/diarrhea
What is the benefit of influenza testing?
- Enable appropriate therapy
- Facilitate prompt treatment
- Some antivirals are only effective if administered within 48 hrs of Sx onset
How many times are you supposed to rotate the swab and how are you supposed to rotate it?
- 3 times; vigorously
What are potential errors dependent on?
Prevalence (highly dependent)
When may false positives occur for Rapid influenza?
- Disease prevalence is low (beginning or end of season)
- Disease prevalence is high (height of influenza season)
How can you minimize false results in rapid influenza?
- Use rapid diagnostic tests with high sensitivity and specificity
- Collect specimens as early in the illness as possible (within 4-5 days)
- Follow manufacturers instruction
What are the limitations associated with negative rapid influenza results?
- Does not exclude infection with influenza A or B
- Test should be used in conjunction with clinical findings to make accurate diagnosis
- Additional testing required to differentiate any specific flu A/B subtypes or strains
What does influenza test performance depend on?
The amount of antigens in the specimen
