Cat fleas and ticks must be controlled if life isn’t to be a misery both for you and your pet and in this case, prevention is definitely better than cure! It is an unfortunate fact that most cats (and dogs) will pick up fleas and/or ticks at some time if they are allowed outside or if a wandering cat is allowed into the house. Yes, even if your cat never sets foot outside your door, a stray may leave its fleas or their eggs behind in your carpet or on your sofa.
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Cat Fleas and Ticks – How to Control Them