Updates on emerging respiratory viruses and diagnostic technologies

Even as the COVID-19 pandemic has receded, novel and new genotypes of respiratory viruses continue to emerge in recent decades. Most of these have been zoonotic RNA viruses from the families Coronaviridae (SARS-CoV-1, MERS-CoV, SARS-CoV-2) and Orthomyxoviridae (pandemic influenza H1N1, variant influenza, avian influenza H5N1, H5N6, H7N9), showing the importance of the One Health concept that human health is closely linked to animals and the environment. Additionally, there have been global outbreaks of unusual genotypes of known respiratory viruses, such as enterovirus D68 and adenovirus types B7 and B14. Novel viruses such as sapovirus and pteropine orthoreovirus are associated with respiratory infections in humans, but are not routinely tested for, leading to a lack of knowledge of prevalence. The conditions predisposing to emergence of respiratory viruses will be discussed. The pandemic led to a major expansion in laboratory capacity for molecular diagnostics and the widespread use and acceptance of point-of-care (lateral flow assay) testing. There is an increasing emphasis on syndromic testing for multiple pathogens, which are now increasingly available at reasonable cost and more easily performed automation. Newer technologies which may become routinely available in the near future include molecular point-of-care tests and metagenomics (next-generation sequencing). However, challenges in the clinical interpretation of molecular testing remain.