Cats actually carry a few parasites, a few fleas and some diseases and a few can change serious but not many. If felines were triggering too much sickness they might not have invaded our lives as well as they have. But you may still find people out there who do nothing like felines. When I first went to China about twenty years ago there have been very few felines coping with people and very few wild felines. I was impressed because I've acquired cats all my entire life and I never thought people didn't like pet cats. But then in China the people said cats taken disease and this was it. I think that might have something regarding that cat sick you get in your attention. Not serious simply a little problem for a week Of course, if you were pregnant you had to stay away from cats. I think they were discussing toxoplasmosis, but if you get that whenever you are a kid it will not affect your child. In addition they said felines were grubby but I don't believe so. I believe cats are one of the cleanest dogs and cats you could have. I feel that came from the cats killing the rats and mice. Because rats are incredibly dirty animals then because the pet cats wiped out and ate them they will also be grubby. A dirty by connection type of thing. Also there were some big sewer rats running round throughout the day. Once I noticed a rat and a kitten face off one another and the kitten wasn't much bigger than the rat. These were about a foot apart staring each other out and the cat ran away. I'm not surprised the rat's teeth were bigger that the cats.
Then the nine lives of the humble cat who only wanted to help mankind by getting rid of rodents that carried disease took a serious convert for the more serious during the dark ages. Where witch hunts and using at the stake were the norm. A person who didn't like felines somehow connected these to witches plus they were burnt at the stake with there owners. That they made that connection I'll never know. It began with Pope Gregory IX in the 1232 who deemed the normal house kitty as diabolical. Then to make issues even worse in1484 along came the greatest feline killer of all time, Pope Innocent VIII, who decreed something along the lines of all cats originated from hell and should went back to the fires of hell by open fire. Cats were mercilessly prosecuted and were burnt so they might go back to the fires of hell. It really is amazing any survived because if you were captured with a feline you were burnt along. I still go to chapel and sometimes I simply wonder why. And of course the Black Death was in the backdrop surviving and thriving because there have been no cats to eliminate the rats that taken the fleas that induced the disease. Then along came the cat's savior King Louis XIII of France, who in the 1630s repealed regulations and cats once again began to live. However they were still hated and killed for many centuries from then on. I don't know if the Black Death subsided but cats once again shielded mankind resistant to the diseases transported by rodents. Plus the famines due to mice plagues.
I think one of the reasons there were not many cats around is because they used to eat them. And once in a while the restaurant kitty catches would grab an kitten they could find and take them back to the restaurant. I remember seeing pet cats in glass shows out leading of the restaurants. But somewhere between then and now they prohibited eating pet cats. So cats are now not on the menu and today there are cats everywhere. Many of them started off in someone's house and acquired thrown away, as a general rule are incredibly friendly. Also they may have this thing about belly worms. And in those days China was not as modern as now so stomach worms would have been a problem. Fleas are not really a problem because they may have tile flooring and real wood furniture.