New virological tools for screening, diagnosis and monitoring of hepatitis B and C in resource-limited settings

Worldwide, the increasingly dominant model of laboratory testing is the centralised laboratory, in which automation of analytical processes increases, enabling the analysis of large numbers of samples at a relatively low cost. However, this trend does not fulfil the requirements for care of patients with chronic hepatitis B and C in resource-limited settings. Alternative models using point-of-care (POC) tests and dried blood spots (DBSs) are increasingly being considered for viral hepatitis screening, diagnosis and monitoring. POC tests are small devices providing qualitative and/or quantitative determination of viral antibodies and/or antigens. They can use original specimen matrices, such as oral fluid or blood collected from a fingerstick. POC tests are particularly useful for large-scale screening, and to improve access to care in regions where laboratory access is limited. New POC devices that detect and quantify viral nucleic acids are at the developmental stage. DBSs offer the main advantage of enabling storage of desiccated blood that can be easily transported to reference centres, where state-of-the-art molecular and serological diagnostic tests are available. However, standardisation and better automation of DBS handling are needed. Herein, we review alternatives to classical hepatitis B and C virological tests, examining POC tests and DBSs, as well as alternatives to nucleic acid testing. Innovations in testing approaches resulting from the availability of these new assays are also discussed.