Application of new technology for the diagnosis of viral infection

Abstract

New technology is challenging conventional methods for characterizing pathogenic viruses in clinical laboratories. These newer methods are superior to older methods due to their ability to broadly target numerous pathogens in multiplexed ways. Even more intriguing, new technologies are capable of detecting viruses in non-targeted manners. Before these newer methods can be adopted by accredited medical laboratories, they must be validated to assess whether or not they meet minimum federal standards in terms of assay accuracy, precision, reproducibility, and cross-reactivity. This thesis begins to answer important questions facing clinical laboratories when adopting new technology. In Chapter 1, assays targeting single virus types are compared to a multiplexed assay using a proprietary electrochemical detection technology to determine if multiplexing has a detrimental effect on analytical sensitivity when detecting respiratory viruses simultaneously. Chapter 2 focuses on the issue of false positivity when testing for viruses in low-prevalence populations. To evaluate this, a multiplex flow immunoassay technology is used to perform surveillance of human immunodeficiency virus (HIV) infection in Alaskans, a low HIV-prevalence population. Chapter 3 describes clinical diagnostic applications of next-generation sequencing (NGS) providing examples of how NGS compares to conventional methods for characterizing pathogenic viruses such as hepatitis C virus, herpesvirus, adenovirus, and influenza virus. The final chapter describes how NGS can be used to characterize viruses by geographical region of transmission by analyzing an outbreak of canine parvovirus that occurred in the interior of Alaska. This chapter serves as a clear example of NGS's appeal to enhancing our epidemiological understanding during outbreaks. Although there are significant challenges to implementation, especially for NGS, each chapter shows promise in new technologies for clinical laboratories.