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Published on: February 11, 2019
Stability of minute virus of mice against temperature and sodium hydroxide
Nicola Boschetti1, Katja Wyss, Anita Mischler
1ZLB Bioplasma AG, Wankdorfstr. 10, 3000 22, Bern, Switzerland. nicola.boschetti@zlb.com
Abstract:
Treatment with steam and/or dilute NaOH are commonly used techniques to disinfect manufacturing vessels and tools in the pharmaceutical industry. The aim of this procedure is sanitisation and inactivation of microbiological and viral contaminants. Here we describe the inactivation of the mouse parvovirus Minute Virus of Mice (MVM) under these conditions. Parvoviruses are known to be resistant to physico-chemical treatment and one representative of this family, the human parvovirus B19, is a potential contaminant of blood plasma. We show inactivation kinetics for MVM treated with wet-heat (70, 80, 90 degrees C) and with 0.01-1 M NaOH solutions (pH >/=11.9). Robust inactivation was only achieved at 90 degrees C for at least 10 min and in NaOH solutions of pH >/=12.8 (0.1 M NaOH). It was observed, that aggregation of viruses might protect viral particles from inactivation by NaOH. Therefore, appropriate sample preparation of spiking material is important for accurate simulation of the naturally occurring situation. The observed stability at pH 11.8 exceeds the previously reported upper limit of pH 9. Inactivation was due to disintegration of the viral capsid as assessed by accessibility of viral DNA for endonucleases.
Insights
Steam and NaOH effectively disinfect pharmaceutical equipment by inactivating Minute Virus of Mice (MVM). Robust viral inactivation requires 90°C steam for 10 minutes or high pH (≥12.8) NaOH solutions.
Area of Science:
- Virology
- Pharmaceutical Manufacturing
- Disinfection Technologies
Background:
- Steam and sodium hydroxide (NaOH) are standard disinfection methods in pharmaceutical manufacturing.
- Effective sanitization is crucial for eliminating microbiological and viral contaminants.
- Parvoviruses, including human parvovirus B19, are known for their resistance to chemical treatments.
Purpose of the Study:
- To investigate the inactivation kinetics of Minute Virus of Mice (MVM), a parvovirus surrogate, under steam and NaOH treatment.
- To determine the specific conditions required for robust MVM inactivation.
- To assess the impact of viral aggregation on inactivation efficacy.
Main Methods:
- MVM was subjected to wet-heat treatment at 70, 80, and 90°C.
- MVM was treated with NaOH solutions ranging from 0.01 to 1 M (pH ≥11.9).
- Viral capsid integrity and DNA accessibility were assessed using endonuclease assays.
Main Results:
- Complete MVM inactivation was achieved at 90°C for at least 10 minutes.
- Robust inactivation required NaOH solutions with a pH of ≥12.8 (0.1 M NaOH).
- Viral aggregation was observed to potentially protect MVM particles from NaOH-mediated inactivation, highlighting the importance of sample preparation.
Conclusions:
- High temperatures (90°C) and high pH (≥12.8) are necessary for effective MVM inactivation.
- The stability of MVM at pH 11.8 surpasses previously reported limits.
- Disintegration of the viral capsid is the primary mechanism of inactivation, as evidenced by increased DNA accessibility.
