Who do rat fleas bite? - briefly
Rat fleas mainly parasitize rodents—particularly rats and mice—but will also bite humans, cats, dogs, and other mammals when their preferred hosts are scarce. Their feeding is opportunistic, extending to any warm‑blooded animal they encounter.
Who do rat fleas bite? - in detail
Rat fleas (primarily Xenopsylla cheopis and related species) are obligate hematophagous ectoparasites. Their primary host is the brown rat (Rattus norvegicus) and the black rat (Rattus rattus), where they complete most of their life cycle. When rat populations decline or when fleas encounter other mammals, they may opportunistically feed on:
- House mice (Mus musculus)
- Domestic cats and dogs
- Humans, especially in densely populated or unsanitary environments
- Other small mammals such as squirrels, feral rabbits, and ground‑dwelling marsupials
Flea attachment depends on host availability, environmental conditions, and flea developmental stage. Adult females require a blood meal to produce eggs; they will bite any warm‑blooded animal that provides sufficient access to skin. Larvae remain in the nest or burrow, feeding on organic debris and adult flea feces rather than directly on hosts. Consequently, while rats are the preferred and most common source of blood, rat fleas can and do bite a variety of mammals, including people, when circumstances permit.