We have had issues in the past - despite using v expensive (and useless) prescription only frontline combo our dog always had one on two fleas on him which we understood he picked up while out walking - we then moved to Bravecto which has been brilliant - not seen a flea since we started using. House is clear as it has been sprayed, hoovered, bedding boiled etc....our dog still doesnt have any fleas despite dog sitting friends dog for past week...
How do I tell friend diplomatically and what can I do to protect my dog and home...???
Where do they pick up fleas from - is it always another dog or out walking???
If it was me I'd just text and be reasonably blunt: "Hi there, sorry to bother you but I've noticed that Dog has got some fleas. I've got some Bravecto here which usually keeps MyDog clear, would you like me to treat Dog or do you use something else?"