The lack of specificity of -based PCR for the detection of carriage in pharyngeal swabs from adolescents.

The utility of the superoxide dismutase C () gene for detecting carriage in pharyngeal swab samples is unclear. While it has been explored as an alternative to the capsule transport A gene for detecting invasive strains, its potential as the sole target for real-time PCR in meningococcal carriage screening remains unexplored. This study aimed to assess the utility of using as a target for detecting invasive and non-invasive strains of in pharyngeal swabs. Oropharyngeal swab samples collected from adolescents (approximately 15-18 years of age) enrolled in the "B-Part-of-It" cluster-randomized controlled trial (NCT03089086) were selected for this study. Samples were initially screened for the presence of specific porin A gene () using PCR and then preserved by freezing at -80°C. An assay targeting the gene was developed using the locked nucleic acid probe-based method. Upon optimization of the assay, 1,092 samples were retested using this assay and compared against the results from the assays to determine concordance. Out of 1,092 samples tested, 965 (88.4%) were positive, with 100% sensitivity and 13% specificity compared to . The positive predictive values and negative predictive values for the C assay were 12% and 100%, respectively. When compared to PCR as the gold standard, the assay lacks sufficient specificity to serve as a stand-alone screening assay for the detection of carriage in pharyngeal samples from adolescents.IMPORTANCEWhile the assay successfully detects , we identified a limitation in its specificity due to potential cross-reactivity with other organisms, including spp., which can result in false positives. This limitation highlights the need for careful interpretation of carriage results, especially in epidemiological studies.