Currently, there are several available methods for collecting oral fluid. However, few community-based studies have investigated which method is optimal for anti-HAV detection; important factors such as low cost, ease of collection, the validity of the results when the samples are stored under sub-optimal storage conditions, and use in a low-tech setting should be considered .
The aim of this study was to evaluate different oral fluid collection devices to determine which XAV939 is more suitable for distinguishing between HAV-susceptible and -protected individuals in community survey studies. The optimization panel was composed of matched serum and oral fluid samples collected from 90 health care workers without epidemiological or clinical factors associated with acute or chronic hepatitis. The health care workers were from the Oswaldo Cruz Institute and were stratified according to the total anti-HAV status of their serum. A total of 55 individuals
had documented immunity to HAV (post vaccination, n = 25; previous infection, n = 30), and 35 individuals were non-reactive for anti-HAV antibodies. The optimization panel was designed to determine the optimal salivary collection device and the most favorable parameters (dilution, incubation time and temperature) for the detection of low titers of anti-HAV antibodies in a commercial immunoassay (ImmunoComb® II HAV Ab, Orgenics, Israel) using serum samples as a reference (referred Ku-0059436 mw to as the “gold standard”). Matched serum and oral fluid samples were collected from each participant. Five milliliters (mL) of peripheral blood was drawn by venipuncture using hypodermic needles and multiple sterile vacuum blood collection tubes (Vacutainer system, Franklin Lakes, NJ, USA). Subsequently, the samples were centrifuged at 1800 × g at 25 °C for 5 min, and the sera were stored at −20 °C. Oral
fluid samples were obtained with three different commercial devices: ChemBio® (ChemBio Diagnostic Systems science Inc., NY, USA), OraSure® (originally provided as an HIV-1 Oral Specimen Collection Device) (Epitope Inc., Beaverton, USA), and Salivette® (Sarstedt, Germany). Oral fluid sample collection and processing procedures are shown in detail in Table 1. Total anti-HAV antibodies were detected with a commercially available, solid-phase enzyme immunoassay (EIA) based on the principle of immunocapture (ImmunoComb® II HAV Ab, Orgenics, Israel). The solid phase is a comb composed of 12 projections. Each projection is sensitized at two positions: an upper spot with a monoclonal anti-HAV antibody (internal control) and a lower spot with rabbit anti-human IgG and IgM antibodies.