"Blinds"  

Venetian, Roller or Roman? I got my last set from Dunelm Mill and very good they were too.

I think you are trying to say "Blindess" , which is a very rare complication of Toxocariasis, which is itself rare in the UK. You can read all about it on the NHS web page here:

https://www.nhs.uk/conditions/Toxocariasis/

It's worth noting from this authoritative source that:

 "If you have a pet cat or dog, they should be regularly de-wormed and their faeces should be disposed of immediately."

So, as long as pet owners de-worm their animals (as most will) and clean up after them (as all but a tiny minority will do on club sites), then there is no issue.

The problem is the very small minority of less than responsible dog owners that do not immediately clean up. To effect change, it is those irresponsible  people who should be targeted, not the responsible majority.

So, as long as pet owners de-worm their animals (as most will) and clean up after them (as all but a tiny minority will do on club sites), then there is no issue.

I doubt that the majority do de-worm regularly

[quote]I doubt that the majority do de-worm regularly[/unquote]

And your evidence for this is? 

No matter.

It doesn't really affect the outcome of course (apart from the animals health), the risk is of Toxocariasis in humans remains low and is made lower by de-worming.

It is reduced further if, according the NHS,  "faeces are disposed of immediately".

Hopefully the wild foxes that can sometimes be seen on this site and others have also read the NHS advice to clean up after themselves.

doubt that the majority do de-worm regularly[/unquote]

And your evidence for this is? 

No more evidence than you but maybe less faith in folk carrying out 'routine' treatment routinely.