TABLE 3.
Comparison of reports of the accuracy the BD Directigen A+B antigen immunoassay
Reference | Yr | Influenza A virus
|
Influenza B virus
|
Age when tested | No. of samples | No. influenza A virus antigen positive | No. influenza B virus antigen positive | Specimena | Reference test(s) | ||
---|---|---|---|---|---|---|---|---|---|---|---|
% Sensitivity | % Specificity | % Sensitivity | % Specificity | ||||||||
8 | 2002 | 96.0 | 99.6 | 87.5 | 96.8 | <2 yr to adultb | 250 | 24 | 28 | NPA | Culture, PCRc |
37 | 2002 | 82.9 | 100.0 | 51.5 | 100.0 | Not availabled | 160 | 34 | 17 | NPA, TSd | Shell vial |
11 | 2003 | 82.4 | 100.0 | 70.0 | 99.6 | Not available | 155 | 14 | 7 | Not available | Shell vial, DFA |
38 | 2003 | 86.7 | 97.7 | 86.3 | 97.8 | 1 day to 31 yre | 200 | 13 | 44 | NPA | Culture |
25 | 2004 | 61.3 | 100.0 | 50.0 | 100.0 | Not availablef | 77 | 19 | 14 | NPA, NPSg | Culture, DFAg |
7 | 2004 | 43.0 | 99.8 | 44.8 | 99.9 | Mean, 3.2 yrh | 4,092 | 49 | 47 | NWi | Culture |
35 | 2007 | 41.0 | 98.0 | 50.0 | 99.0 | Median, 44 yrj | 118 | 15 | 3 | NPS | Culture |
39 | 2007 | 53.0 | 99.7 | 33.0 | 100.0 | Median, 34 yr | 354 | 38 | 2 | NPW, TS, NW | Culture |
This study | 2008 | 61.4 | 99.2 | 42.9 | 100.0 | Median, 1.8 yrk | 180 | 27 | 3 | NPA, NPS | Culture, PCR |
NPA is nasopharyngeal aspirate, TS is throat swab, NPS is nasopharyngeal swab, and NW is nasal wash.
80% of specimens from persons <6 years old.
PCR used for specimens that were culture negative but positive by antigen immunoassay or direct immunofluorescence antigen microscopy.
Nasopharyngeal aspirates from pediatric patients (62.2% of positives) and throat swabs from adults (37.8% of positives).
36.5% of the specimens were from pediatric patients.
56.2% of the specimens were from pediatric patients.
Specimens for antigen testing and culture were initially frozen.
2% of the patients were >18 years old.
98% nasal wash, 0.22% nasopharyngeal swab, 1.7% tracheal aspirate, 0.17% bronchoalveolar lavage, 0.1% sinus wash, and 0.06% sputum samples.
Overall estimate with combined specimens for antigen testing and DFA.
Data are from this study (the mean and median ages of influenza virus-positive patients were 42.7 and 42.4 years, respectively), where 33 of 50 samples were influenza A virus positive, 3 of 6 samples were influenza B virus positive, and 10 of 38 nasopharyngeal swab samples were influenza virus positive.