Let's address the basic issue here -- contamination. I don't know how it might be in the UK, (and am not sure as to which side of the pond you are located) but I know in the USA there are companies whose sole purpose is decontaminating homes in the aftermath of such a catastrophe. The entire cost of their work is normally paid in full by homeowners' insurance. In all likelihood the decontamination crew will completely remove the carpeting for you! Check with your insurance company. They will certainly have some contact information for the decon company nearest you.