Microfibre has reportedly antimicrobial efficacy already, if looking for virus protection then a cleaning fluid that is effective against viruses needs to be used.
There has been a disscussion of the effectiveness of microfibre on this site already:
One article that seemed to cover all the basics of using these cloths I linked in the article and I have re-posted here:
The silver coating will probably make the cloths smell fresher for longer but the reality is that they should be laundered every day after use to keep them clean so shouldn’t really need the silver coating. They also note that the silver coating isn’t permanent by saying it only lasts 100 washes or thereabouts (they actually say “Silver Treatment is good for over 100 washes” but no hard and fast figure on that). Based on washing them everyday you use them and if used everyday this is about 4 months before the silver coating is no longer present.
Even the statement “Antibacterial microfiber cloth embedded with liquid silver designed to kill bacteria” is a bit of puffery. Liquid silver? It has a high melting point so absolutely doubt it is liquid silver and more likely a silver compound of some type, efficacy then unknown.
