title: A simple assay for determining antiviral activity against Crimean-Congo hemorrhagic fever virus.
abstract: Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus that is emerging as a significant human pathogen in many regions of the world, including Africa, Asia, and Europe. In this report, we describe a simple screening method for discovering new antiviral compounds directed against CCHFV. Antiviral activity was determined by assaying infected SW-13 cells (human adrenal gland carcinoma) for protection from cytopathic effect (CPE). By using an in vitro neutral red uptake assay, we were able to quantitatively measure CPE induced by CCHFV. As a proof of concept, we used this method to evaluate the antiviral activity of ribavirin and a series of structural analogs (ribamidine, 6-azauridine, selenazofurin, and tiazofurin) against four geographically diverse strains of CCHFV. Ribavirin inhibited the replication of CCHFV as reported previously using plaque reduction assays. One drug, ribamidine, showed antiviral activity that was 4.5- to 8-fold less than that of ribavirin, and the other three drugs (6-azauridine, selenazofurin, and tiazofurin) did not show significant antiviral activity. There were no significant differences in drug sensitivities among the CCHFV strains. Development of this simple and reliable assay will potentially allow high-throughput screening for discovering additional antiviral drugs to combat this important public health threat.
authors.affiliation: Virology Division, United States Army Institute of Infectious Diseases, Fort Detrick, MD 21702-5011, USA. Jason.Paragas@amedd.army.mil
authors.forename: Jason
authors.initials: J
authors.lastname: Paragas
authors.forename: Chris A
authors.initials: CA
authors.lastname: Whitehouse
authors.forename: Timothy P
authors.initials: TP
authors.lastname: Endy
authors.forename: Mike
authors.initials: M
authors.lastname: Bray
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D001380:Azauridine / Q000494:pharmacology; D002460:Cell Line; D002522:Chlorocebus aethiops; D004396:Coloring Agents / Q000378:metabolism; D006224:Cricetinae; D005347:Fibroblasts; D003225:Hemorrhagic Fever Virus, Crimean-Congo / Q000187:drug effects* / Q000254:growth & development; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods*; D009499:Neutral Red / Q000378:metabolism; D016566:Organoselenium Compounds / Q000494:pharmacology; D012254:Ribavirin / Q000031:analogs & derivatives* / Q000494:pharmacology; D012263:Ribonucleosides / Q000494:pharmacology; D013194:Staining and Labeling; D014709:Vero Cells; D010948:Viral Plaque Assay; D014779:Virus Replication / Q000187:drug effects
chemical_list: D000998:Antiviral Agents; D004396:Coloring Agents; D016566:Organoselenium Compounds; D012263:Ribonucleosides; D009499:Neutral Red; D012254:Ribavirin; D001380:Azauridine; C039064:selenazofurin; C026956:taribavirin; C033706:tiazofurin