The results of the test are visible as gray-blue spots on the surface of the projections, and the visual results are determined semi-quantitatively by comparing the intensity of the color of the lower spot on each projection with the color scale provided by the manufacturer. The results of the samples were classified according to the cut-off point (10 IU/L) of the test. A spot with an intensity greater to or equal than the cut-off point indicated the presence of protecting anti-HAV levels. A spot with an intensity slightly less than that of the cut-off was considered an equivocal result, and the sample
was retested. A spot with a lower intensity than that of the cut-off was considered negative. The ImmunoComb® II HAV Ab assay has a limit of detection selleck chemicals llc of 10 IU anti-HAV antibodies/L, which is regarded as the minimum concentration of anti-HAV antibodies that Aurora Kinase inhibitor indicates immunization has occurred. All of the samples were assayed three times, and identical visual readings for HAV were consistently observed by multiple investigators (three) for all samples. After determining the optimal salivary collection device, its applicability in a surveillance setting
was determined. This study was performed in four isolated communities in South Pantanal, Brazil, in difficult-to-access areas that are 661 km from the city of Campo Grande. This region is sparsely populated and is characterized by wetlands that hinder access to the coastal communities; access is only available by boat. For these reasons, fishing is the primary source of income and
livelihood for the majority of the population. The survey was conducted between April and June 2010, Cell press and the ChemBio® device was used to collect 224 matched serum and oral fluid samples using a non-probability sampling method from all consenting occupants of households. The entire population consisted of 691 individuals. The samples were placed in a cool box and returned to the laboratory after 15 days of collection for a total anti-HAV screening test. The sociodemographic characteristics of each member of the study were obtained with questionnaires. The influence of temperature and time exposure on the detection of anti-HAV antibodies in oral fluid samples was investigated. The parameters were based on the manufacturer’s storage instructions. Five concordant, matched samples (3 anti-HAV positive and 2 negative) that were collected in difficult-to-access areas of South Pantanal were selected for follow-up to evaluate anti-HAV antibody stability. Due to the unavailability of cooling in the surveillance setting, the oral fluid samples remained at unstable temperature conditions for 15 days. At the end of this exposure, the samples were sent to a laboratory in Rio de Janeiro and were centrifuged and refrigerated at 2–8 °C until the first analysis (15 days after collection). The samples were stored for 210 days after collection and were retested every 30 days.