Hi everyone,
Many thanks to everyone who took the time to reply to this when I posted originally. I had made up my mind to go with the Parvo-Virucide - after all, who wants to take chances when it comes to puppies! I wanted something that would take care of ALL the nasties!
I went down to Crufts with my list and found the Animal Health stall and asked them about the Parvo-Virucide. They informed me that this product should not be used in a whelping box and indeed, should not be used indoors. This product, they told me, was for outdoor kennel use. Instead they told me that another product (the name escapes me) was what they recommended for whelping boxes and use around young puppies. Basically this was a sterilising agent like Milton. I then checked this information at the Vet-Medic stall and asked whether Milton (or similar) is what he would recommend for use within a whelping box - he agreed this was a suitable product.
I know many of you have used Parvo-Virucide for many years with no ill effects, but I thought I would share with you the information I had received. It may change what you use...it may not!
Thanks again for all your help!