Background

During the SARS-CoV-2 pandemic, the use of surgical style masks increased significantly. Studies found that respiratory viruses build upon the outer surface of masks, such that mask outers are considered as highly contaminated after use. Our client developed a Type IIR surgical mask with an antiviral outer layer and wanted to demonstrate antiviral performance of their mask according to standard ISO 18184. Additionally, our client required bespoke testing of their mask to better demonstrate real world use.

Methods and results

As well as demonstrating excellent antiviral activity following standard ISO 18184, our expert scientists at Virologica were able to design and execute a series of novel experiments to add value by underlining the performance of our client’s product. With duration of mask wear increasing and therefore potential for multiple viral exposures, repeat inoculation studies were performed over extended time periods – out to 8 hours contact. Viruses are transmitted in very fine suspensions or aerosols; to represent this, we challenged the antiviral mask with aerosolised inoculum. Against human coronavirus 229E, the mask was up to 99.99% effective in repeat inoculation and aerosol inoculation studies.

Researchers have demonstrated that during routine removal, viral contamination can be efficiently transferred from PPE (including masks) to the wearer’s skin or clothing. We devised a bespoke transfer test method and demonstrated that virus could be readily transferred from control masks but not from the antiviral Type IIR surgical masks.

Conclusion

Using Virologica’s excellent data, our client has now successfully registered their medical device with the UK MHRA. In addition, the innovative experiments designed in collaboration with Virologica strongly support the performance and marketing of their product.