Use of guanidine thiocyanate-based nucleic acid extraction buffers to inactivate poliovirus in potentially infectious materials

The efforts of the Global Poliovirus Eradication Initiative (GPEI) have brought about the near elimination of poliovirus worldwide. The World Health Organization has issued guidelines for the safe handling and containment of infectious materials (IM) and potentially infectious materials (PIM) following poliovirus eradication. Inactivation of poliovirus in IM and PIM is needed to prevent inadvertent re-introduction of polioviruses post-eradication. In this study, we investigated the use of guanidine thiocyanate-based nucleic acid extraction buffers from commercially available nucleic acid extraction kits to inactivate poliovirus in cell culture isolates and stool suspensions, two common types of poliovirus IM and PIM, respectively. Incubation with selected nucleic acid extraction buffers or extraction buffers supplemented with ethanol reduced the infectivity of high-titer wild poliovirus type 1 (WPV1), wild poliovirus type 3 (WPV3), Sabin 1 (SL1), and Sabin 3 (SL3) cell culture isolates below the limit of detection in CCID₅₀ assays. Stool suspensions containing WPV1, WPV3, SL1, SL2, or SL3 were also inactivated by the extraction buffers tested. Blind passage of WPV1-spiked stool suspensions confirmed complete inactivation of WPV1 after incubation with extraction buffers. Moreover, treatment with a buffer consisting of 4 M guanidine thiocyanate with 30 % ethanol inactivated a high-titer WPV1 culture isolate and a WPV1-spiked stool suspension. Taken together, these results show that guanidine thiocyanate-based nucleic acid extraction buffers are an effective means of inactivating poliovirus IM and PIM, and thus will be instrumental in ensuring containment compliance and preventing potential re-emergence of contained polioviruses.