Nonstructural protein 1 (NS1) Ag-based tests are useful for detecting dengue virus (DENV), but there is lack of evidence on the diagnostic accuracy of NS1 Ag-based tests in Asian population. Thus, we conducted this meta-analysis to obtain the overall estimated and summarized performance of the NS1 Ag-based tests in the detection of DENV in Asia.
PubMed, Embase and Medline were searched for studies that evaluated the diagnostic validity of NS1 Ag-based tests between January 1990 and November 2014. Data were analyzed by Meta-Disc and STATA software.
A total of 18 studies including 3342 dengue cases and 1904 control cases which fulfilled the inclusion criteria were considered for analysis. The pooled sensitivity and specificity for NS1 Ag-based tests was 66 % (95 % CI 64.5-67.5) and 97.9 % (95 % CI 97.3-100), respectively. STRIP has the overall highest sensitivity (72.9 %, 95 % CI 70.1-75.5). According to viral serotype, the test with the highest sensitivity for DENV1, DENV2 and DENV3 were Platelia (83.7 %, 95 % CI 79.7-87.1), Panbio (71.8 %, 95 % CI 65.5-80.9) and STRIP (81.9 %, 95 % CI 75.5-87.2) respectively. The highest sensitivity for primary infection was Platelia (95.1 %, 95 % CI 92.6-96.9) and for secondary infection was STRIP (64 %, 95 % CI 53.2-73.9).
Our meta-analysis suggests that NS1 Ag-based test is a good diagnostic method for DENV with a high specificity. However, viral serotype, serological status, clinical severity and the duration of illness are the main factors influencing the diagnostic accuracy.