What hosts do bed bugs parasitize? - briefly
Bed bugs are hematophagous insects that primarily parasitize humans, extracting blood for nourishment. They may also bite other warm‑blooded animals—such as birds, rodents, and domestic pets—when human hosts are scarce.
What hosts do bed bugs parasitize? - in detail
Bed bugs (Cimex spp.) are obligate hematophagous insects that require vertebrate blood to complete their life cycle. Their primary host is humans, on whom they depend for the majority of feeding events. Human blood provides the nutrients essential for development from egg to adult, and infestations are most common in residential and institutional settings where people sleep or rest for extended periods.
In addition to humans, bed bugs can exploit a limited range of alternative vertebrate hosts:
- Other mammals – domestic dogs, cats, rodents, and livestock have been recorded as occasional blood sources. Feeding on these animals usually occurs when human hosts are unavailable or when infestations develop in environments with high mammalian density, such as barns or shelters.
- Birds – occasional feeding on domestic poultry and wild birds has been documented, particularly in structures where birds roost near human sleeping areas. Bird blood supports development but is less preferred.
- Bats – rare reports describe bed bugs feeding on bats in cave or attic colonies, reflecting the insects’ capacity to locate warm-blooded hosts in confined spaces.
- Exotic or captive wildlife – zoos and wildlife rehabilitation centers sometimes report bed bug presence on non‑human species, though infestations remain sporadic.
Host selection relies on thermal, carbon‑dioxide, and kairomone cues. Humans emit a combination of heat and CO₂ that attracts the insects most efficiently, explaining their strong association with human dwellings. When these cues are absent, bed bugs may extend their search to other warm‑blooded animals, but the frequency and success of such feedings are considerably lower.
Successful colonization of non‑human hosts often correlates with prolonged exposure, high host density, and limited competition from preferred human hosts. Nonetheless, the insects’ physiological adaptation restricts them to a narrow host spectrum, with mammals providing the optimal blood composition for growth and reproduction.