Using lawn after dog breeder

[InFrance2014]

Hi,
I'm buying a house with a garden that a dog breeder has used, inc. a lawn. She had 12 dogs, mostly whippets, and seems a very reputable individual so I think will have wormed etc.
I have two very small children and would like to know what we should do in terms of hygiene- how long should we leave the lawn to cleanse itself for, should we replace soil etc?

Thanks in advance

If you are in Europe the rain will have washed anything away.

as long as theres no shit left behind, I wouldnt do anything special

Thanks for replies!