Abstract
Saliva contains antibodies potentially useful for determining serostatus for surveillance and vaccination studies. However, antibody levels are low, and degradation by endonucleases is problematic. As a simple, non-invasive alternative to blood we developed a method for detecting viral antibodies from oral flocked swabs. Serum, saliva, and oral swabs were collected from 50 healthy volunteers. Sera and saliva were stored at −80°C. Dried swabs were stored at room temperature. Seroprevalence for Cytomegalovirus (CMV), Varicella Zoster virus (VZV), Epstein-Barr virus (EBV), Measles and Mumps IgG antibodies were determined using commercial ELISA assays and processed on the ThunderBolt® Analyzer (Gold Standard Diagnostics). For each antibody, swabs correlated well with saliva. For CMV IgG, the swab sensitivity and specificity compared to serum were 95.8% and 100%, respectively. For VZV IgG, swab and saliva sensitivity were 96.0% and 93.9%, respectively. As all volunteers were seropositive for VZV and Measles, specificity could not be determined. For EBV EBNA-1 IgG and VCA IgG, swab and saliva sensitivity were 92.1% and 95.5%, respectively; specificities were 100%. For Measles IgG, swab and saliva sensitivity were 84.5% and 93.9%, respectively. Mumps IgG displayed poor sensitivity for oral swabs (60.5%) and saliva (68.2%), but both were 100% specific. Dried oral swabs correlated well with serum for CMV, VZV, EBV and Measles antibodies with excellent sensitivity and specificity, but had poor sensitivity for detecting antibodies to Mumps. As oral flocked swabs are easy to self-collect and can be stored at room temperature they are an ideal tool for seroprevalence studies.
