Ah, I love it when people with no real knowledge of the subject (e.g. diseases of humans / animals, etc.) find something on the Web and start quoting it to justify whatever their current beliefs may be.
e.g. Toxoplasmosis. Yes, a lot of people have it and many other parasites. Parasites are successful precisely because they rarely cause their host real problems (provided they are reasonably healthy).
Parasites do not come just in meat.
Another couple of scenarios for contracting Toxoplasmosis:
1. You Grow your own vegetables because it is healthier
2. A cat infected with Toxoplasmosis goes bye and takes a crap
3. You don't wash your vegetables too much because hey, they're organic
4. You eat the vegetables -> hello, you're infected
1. You have a cat
2. One day it contracts Toxoplasmosis (it ate something that had it)
3. You clean its litter tray but forget to properly wash your hands.
4. You grab a snack -> hello you're infected
Conclusion. To be safe from this particular disease:
1. Wash your vegetables in bleach
2. Shoot cats on site.
3. Don't eat undercooked meat
The first scenario I mention is of course fairly far fetched. The second one actually isn't although by far the most common way to get this particular parasite infection is from undercooked meat.
After all I don't want anyone going out there to shoot cats. I make some of my living by treating animals (I have a Veterinary degree).
I have also seen first hand how animals are slaughtered for food. It isn't pretty, but these days there are laws that in most cases ensure that it is done quickly.
Vegetarianism and even more so veganism by choice seems to be a lot more prevalent in affluent heavily urbanised societies where people find it hard to reconcile the food they buy in supermarkets (all wrapped nicely) with the reality of how it got there. That leads to the guilt when they think that the cute pig/chicken/cow they usually see only on TV is one day likely to end up as a slab of meat...
Anyway, enough of a rant for one day