Hi Keith
I'm not aware of any cleaning products than contain silver although I am aware of its effect on bacteria (not sure though how it works on viruses and spores etc) There is a product called Biocote which is licensed to manufacturers of equipment (furniture, washroom fittings, beds, etc) which is a permanent coating rather than a cleaning product and I believe it contains silver.
We've just taken on board a product called Steri7 which is a cleaning product that has a 7 day residual effect on bacteria, viruses and spores (and kills bird flu). The product is unique, there is a massive market for it (the NHS currently have it on trial) and it really does work.
I'll be posting some more information about it here shortly and it will soon be added to our website but we have it in stock and are already talking to sub-distributors about it.
If you, or anyone else, wants any more information on it please get in tough
Regards
Mike Boxall