Table 2.

Advantages and disadvantages of diagnostic approaches used with influenza A viruses.

Diagnosis approach	Advantages	Disadvantages
Clinical symptoms	Mild to severe illness Usually occurs during cold months Recovery in 2 days to 2 weeks	May occurs outside the typical seasons May develop a serious complication leading to death Other viruses can cause similar symptoms, e.g., COVID-19
Rapid influenza diagnostic tests (RIDTs)	Used point-of-care tests Results are available within 10–15 min Sensitivity can vary (50–70%), especially if the viral load is low	High chance for false negative results
Reverse transcription polymerase chain reaction (RT-PCR)	Most accurate and reliable Differentiate between influenza types (A or B) and subtypes High sensitivity and specificity Results typically take several hours	Results affected by the sample Requires specialized equipment and trained personnel Requires specialized laboratory
Immunofluorescence assays	Provides results within a few hours Used to identify specific type of influenza	Requires specialized equipment and trained personnel Requires specialized laboratory
Serological assays	Detect influenza virus in the blood Helpful in retrospective diagnosis or sero-prevalence studies Useful for epidemiological studies than for clinical diagnosis	Not used for the initial diagnosis of acute influenza Requires specialized equipment and trained personnel Requires specialized laboratory
Viral culture	Highly specific Not used for routine diagnosis Important for strain surveillance and research purposes	Time-consuming, requiring several days to obtain results Requires specialized laboratory Requires trained personnel
Molecular assays	High sensitivity and specificity Provides results within 30–60 min Used to distinguish among various subtype of influenza Effective in detecting low viral load Suitable for use in portable devices	Requires trained personnel Relatively expensive