I have just been reading a thread on this site about dogs licking, and how dog owners are saying it is perfectly safe and the chances of catching T.C. are very remote, " there has been 1 case of someone going partially blind in the last ten yrs through toxicara canis".
I cannot believe the ignorance of some of these dog owners.  My sister caught toxicara at the age of 5 and became totally blind in one eye. My parents did not have dogs this was caught from someone elses. (it was not caught by cats, they carry a completely different strain that is dangerous to unborn babies)
The worm eggs can live in soil for years and years and can survive most household disenfectants.They can be picked up easily by dogs in the garden and passed on in their saliva. The damage doesn't always appear in the eyes, it can cause damage in other human organs.  Please don't get me wrong I LOVE DOGS, but we must not forget about hygeine issues with any animal, especially when it can damage the health of a child.

I can understand that you are upset about such a horrible thing happening to your sister.  I think it is more an issue about dogs being regularly wormed, beyond that, I believe it is a balance thing, dogs lick kids whether we want to stop it or not we need to cover the bases, like worming, and then either just relax about it and accept that for the huge majority of children a pet does nothing but good or decide that as a nation we will not take the risk to the tiny few and do away with pets all together.

Re Cats you are thinking of Toxoplasmosis.  Cats also carry roundworm, Tocacar Cati I beleive which act in the ame way, and can cause same problems as the canine variety.  In fact I would hazard a guess that fewer cat owners worm their cats,and cats tend to use kiddies sandpits and other peoples gardens as toilets.

As you said it is sensible to be aware, but not paraniod.  Most of the publicity surrounding this has been used to vilify dogs, not to point out a helth risk as the risks are similar for any of the Toxacara species of worm, carried by Dogs, Cats, Urban Foxes etc.