Human respiratory viruses include a broad range of viruses that infect respiratory cells, cause respiratory and other symptoms, and are spread primarily through the respiratory secretions of infected individuals. Respiratory viral infections are often clinically indistinguishable. Respiratory viruses belong to different virus families and differ in viral and genome structure, susceptible populations, disease severity, seasonality of circulation, transmissibility, and mode of transmission. The RNA viruses of the Mononegavirales order contain a negative-sense single-stranded genome. The order consists of 7 families, including Orthomyxoviridae (e.g., influenza virus) and Paramyxoviridae (e.g., parainfluenza viruses, human respiratory syncytial virus, and human metapneumovirus). Members of both families are enveloped; unlike the viruses of the Paramyxoviridae family, the viral genomes of the Orthomyxoviridae family are segmented. The Picornaviridae (e.g., rhinoviruses and enteroviruses) is a non-enveloped virus with a positive polarity single-stranded genome. Viruses of the Coronaviridae family also contain positive-sense single-stranded RNA (ssRNA) but are enveloped. This family currently includes five members known to infect humans: human coronavirus (HCoV) 229E, HCoV OC43, the severe acute respiratory syndrome-associated CoV (SARS-CoV), and the recently described HCoV NL63 and HCoV HKU1. DNA viruses associated with human respiratory diseases include non-enveloped double-stranded DNA (DsDNA) viruses from the family Adenoviridae and a newly discovered single-stranded DNA virus from the family Parvoviridae, termed human bocavirus (HBoV).
Given the high disease burden in both immunocompetent and immunocompromised hosts, antiviral drugs targeting respiratory viral infections are clearly unmet. The lack of rapid, sensitive, and inexpensive diagnostic tests that can differentiate between various respiratory pathogens at the point of care has been a key factor slowing interest in drug development. The lack of a diagnostic platform makes it difficult and time-consuming to assess the true burden of disease in various settings. But, perhaps more importantly, it also limits the ability to conduct clinical trials in settings other than highly specialized transplant centers.
The development of antiviral drugs requires a detailed understanding of the replication of individual viruses and their intimate association with normal host cell activity. Creative Diagnostics facilitates respiratory virus antiviral research and development, including SARS-CoV-2, human coronaviruses, influenza viruses, and respiratory syncytial virus. Our in vitro testing services include viral screening tests as well as tests to evaluate promising candidates, including their range of action, the effectiveness of drug combinations, the potential for resistance selection, and phenotypic/genetic characterization of resistant strains. For in vivo efficacy studies, we provide in vivo model development and testing services. High-potential candidates can be rapidly identified through our screening assay, with simultaneous efficacy and cytotoxicity assessments.
(Other viruses antiviral services may be available on request)
For additional information about Respiratory Viruses Antiviral Services, please contact us.