Bacterial filtration efficiency and viral filtration efficiency of face masks – the role of bacteriophages in textile testing

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00013251%3A_____%2F23%3AN0000007" target="_blank" >RIV/00013251:_____/23:N0000007 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Bacterial filtration efficiency and viral filtration efficiency of face masks – the role of bacteriophages in textile testing

Original language description

Bacterial filtration efficiency (BFE) is, according to EN 14683 + AC, the main characteristics of medical face masks effectivity and quality. The method is based on the analysis of bacterial aerosol in Andersen cascade impactor (ACI) containing six stages simulating the different parts of the respiratory tract. The aerosol particles are separated on the base of their aerodynamic size and sediment on agar medium in Petri dishes filled in the impactor. The use of the glass Petri dishes is recommended for the correct particle sedimentation in ACI, but the most laboratorie prefer the disposable plastic dishes, actually. In our study we evaluated the use of plastic dishes in ACI for determination of BFE of medical face masks. The bacterium Staphylococcus aureus, used for BFE testing, allows only limited detection of submicron aerosol particles (on the sixth stage of the ACI). This limitation can be overcome by the use of bacteriophage aerosol and the method of viral filtration efficiency (VFE) testing. The bacteriophage Phi-X 174 with E. coli host bacterium was chosen for VFE determination. Th edetermined BFE abd VFE values correlate well in the case of masks with high filtration efficiency (99% and more). On the other side, lower values of VFE, comparing with BFE were determined for masks with the filtration efficiency in the range of 95% - 98%. There were detected higher numbers of plaque forming units (PFU) on the sighth stege of ACI in the case of VFE determination in comparison with colony forming units (CFU) in the case of BFE determination. VFE testing gives more exact inforrmation about the ability of tested mask material to filter viral particles carried by submicron aerosol particles. It seems appropriate to supplement the testing of face masks with the test of VFE.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

10606 - Microbiology

Project

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Continuities

N - Vyzkumna aktivita podporovana z neverejnych zdroju

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů