Just like ticks they not only bite the animal they suck their blood. (everydayroots.com)
When a susceptible mosquito bites an animal with microfilariae in the blood, it ingests the microfilariae along with the blood. (tampabayvets.net)
Unique to K9Advantix, in addition to killing all stages of the flea life cycle, the company that makes it claims that the product repels the fleas to begin with The adult fleas typically do not have a chance to bite the animal with these topical products making them a good choices for flea - allergic pets. (web-dvm.net)