...we have determined the diameters of mature and immature HIV-1 to be 110 to 128 and 132 to 146 nm, respectively... Determination of the size of HIV using adenovirus type 2 as an internal length marker. - PubMed - NCBI 110 nanometers = 0.11 micrometers Convert nm to um - Conversion of Measurement Units so the HIV (AIDS) is half as big as the 0.22 um filters pore and can pass unfiltered In the processing of biologics, viruses must be removed or inactivated, requiring the use of nanofilters with a smaller pore size (20–50 nm) are used. Smaller pore sizes lower the flow rate, so in order to achieve higher total throughput or to avoid premature blockage, pre-filters might be used to protect small pore membrane filters. Sterilization (microbiology) - Wikipedia The problem is that oil being so thick may not pass trough 20-50 nanometer filters. And the HIV is a relatively large virus, most other viruses are smaller, so they can well pass trough unfiltered. It looks like 70% ethyl alcohol degrades most viruses proteins, rendering them inactive on evaporation https://www.researchgate.net/profil...8c582ab6bc0000000/Inactivation-of-viruses.pdf You can pour raws on a beaker or shallow pan, pour enough 70% ethyl alcohol to fully cover raws, and allow it to fully evaporate to "kill" viruses. Best if you only pour a shallow layer for faster evaporation.