Posted: 01/11/2015 at 15:33
Well, T Bird if there was any problem then me and 'her indoors' would be dead a long time ago. We have had rats nesting in the compost heap every year for the last 20 years or so (country living). Now admittedly our rats are field rats rather than sewer rats (no sewers here) so less likely to be extremely diseased, but even so.
And the animal manure which farmers spread on their fields is just as likely to be contaminated with rat urine, or in the case of the chicken manure which is spread on the land round here, every bacterium you can imagine, you could get totally paranoid about it.
Soil bacteria are excellent at sterilising compost.