Cats and humans are supposed to be safe.  Don't rely on the Scalibor collar.  We put one on our dog but she still caught Leishmania.  Luckly, we have her on a programme at our vet's which includes  testing for the disease, and it was picked up earlier this year whihc means that we were able to start treating straightaway.  She had to have two injections a day for the first month as well as two tablets.  Subsequent bood tests have shown that these have protected her organs and skin from being affected .  Unfortunately, she will have to stay on one tablet a day for the rest of her life, but these are not expensive, and even if they weren't it is a small price to pay for such a faithful friend