MJ, I promised you info on cleaning after Marek’s.
In the US, Virkon S has a label that lists Marek’s disease virus as one of the viruses it kills. It is used as an agricultural cleaner. I am attaching a link to the label.
https://www3.epa.gov/pesticides/chem_search/ppls/039967-00137-20201022.pdf
Activated Oxine is also something that kills viruses and is used as a poultry house cleaner after AI infections. Its label doesn’t mention specific viruses but I think it kills everything. You activate it using citric acid which is innocuous enough but I believe its mechanism of action is chlorine so is a ‘kills all known’ sort of thing.
https://www3.epa.gov/pesticides/chem_search/ppls/009804-00001-20200409.pdf
Read the labels and instructions carefully. Both are used in poultry farming. I suspect though that the chickens should not be present while you use either of them and I also suspect they are gloves and basic mask type products. I may be being overly cautious - but these are both industrial strength cleaners.
Tax: Tassels trying to hatch ice cubes. Yes, she is sitting on a block of ice that I was using to try and break her broodiness. We are well into the 4th week (second week mainly in a broody jail) but she is stubborn!  I am leaving on my trip now (takeoff any minute) so my chicken sitter will have to take her out to make sure she gets to run around and exercise each day.
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