Infectious titres of human papillomaviruses (HPVs) in patient lesions, methodological considerations in evaluating HPV infectivity and implications for the efficacy of high-level disinfectants
Michelle A. Ozbun,
Virginie Bondu,
Nicole A. Patterson,
Rosa T. Sterk,
Alan G. Waxman,
Erica C. Bennett,
Rohini McKee,
Ankur Sharma,
Jeremy Yarwood,
Marc Rogers,
Gary Eichenbaum
Affiliations
Michelle A. Ozbun
Department of Molecular Genetics & Microbiology, The University of New Mexico School of Medicine, Albuquerque, NM 87131, United States; Department of Obstetrics & Gynecology, The University of New Mexico School of Medicine, Albuquerque, NM 87131, United States; The University of New Mexico Comprehensive Cancer Center, Albuquerque, NM 87131, United States; Corresponding author at: Department of Molecular Genetics & Microbiology, The University of New Mexico School of Medicine, Albuquerque, NM 87131, United States.
Virginie Bondu
Department of Molecular Genetics & Microbiology, The University of New Mexico School of Medicine, Albuquerque, NM 87131, United States
Nicole A. Patterson
Department of Molecular Genetics & Microbiology, The University of New Mexico School of Medicine, Albuquerque, NM 87131, United States
Rosa T. Sterk
Department of Molecular Genetics & Microbiology, The University of New Mexico School of Medicine, Albuquerque, NM 87131, United States
Alan G. Waxman
Department of Obstetrics & Gynecology, The University of New Mexico School of Medicine, Albuquerque, NM 87131, United States
Erica C. Bennett
Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, The University of New Mexico School of Medicine, Albuquerque, NM 87131, United States
Rohini McKee
Department of Surgery, Division of General Surgery, The University of New Mexico School of Medicine, Albuquerque, NM 87131, United States
Ankur Sharma
Advanced Sterilization Products, Inc., 33 Technology Drive, Irvine, CA 92618, United States
Jeremy Yarwood
Advanced Sterilization Products, Inc., 33 Technology Drive, Irvine, CA 92618, United States
Marc Rogers
Advanced Sterilization Products, Inc., 33 Technology Drive, Irvine, CA 92618, United States
Gary Eichenbaum
Johnson & Johnson, Office of the Chief Medical Officer, 410 George Street, New Brunswick, NJ 08901, United States
Background: Recent publications from a single research group have suggested that aldehyde-based high-level disinfectants (HLDs), such as ortho-phthalaldehyde (OPA), are not effective at inactivating HPVs and that therefore, patients may be at risk of HPV infection from medical devices. These results could have significant public health consequences and therefore necessitated evaluation of their reproducibility and clinical relevance. Methods: We developed methods and used standardised controls to: (1) quantify the infectious levels of clinically-sourced HPVs from patient lesions and compare them to laboratory-derived HPVs, (2) evaluate experimental factors that should be controlled to ensure consistent and reproducible infectivity measurements of different HPV genotypes, and (3) determine the efficacy of select HLDs. Findings: A novel focus forming unit (FFU) infectivity assay demonstrated that exfoliates from patient anogenital lesions and respiratory papillomas yielded infectious HPV burdens up to 2.7 × 103 FFU; therefore, using 2.2 × 102 to 1.0 × 104 FFU of laboratory-derived HPVs in disinfection assays provides a relevant range for clinical exposures. RNase and neutralising antibody sensitivities were used to ensure valid infectivity measures of tissue-derived and recombinant HPV preparations. HPV infectivity was demonstrated over a dynamic range of 4–5 log10; and disinfection with OPA and hypochlorite was achieved over 3 to >4 log10 with multiple genotypes of tissue-derived and recombinant HPV isolates. Interpretation: This work, along with a companion publication from an independent lab in this issue, address a major public health question by showing that HPVs are susceptible to HLDs. Funding: Advanced Sterilization Products; US NIH (R01CA207368, U19AI084081, P30CA118100).
