Чем отличается укус блохи от укуса комара? - briefly
Flea bites appear as small, clustered red punctures with intense itching and often develop a central dark spot, while mosquito bites are single, raised welts that swell quickly and itch less aggressively. Flea saliva contains anticoagulants that cause prolonged irritation, whereas mosquito saliva mainly triggers a mild histamine response.
Чем отличается укус блохи от укуса комара? - in detail
Flea bites occur when the insect pierces the skin with a short, serrated mouthpart, draws blood, and often injects saliva containing anticoagulants. The resulting puncture is typically 1–3 mm in diameter, appears as a tiny red spot surrounded by a halo of inflammation, and frequently clusters in groups of two to five bites. The reaction peaks within a few hours, producing intense itching and, in some individuals, a raised wheal that may develop a central puncture mark. Flea saliva can trigger allergic sensitization, leading to larger papular eruptions or, rarely, a systemic hypersensitivity response.
Mosquito bites are delivered by a slender proboscis that penetrates the epidermis without cutting tissue. The puncture is usually invisible; the visible lesion is a raised, erythematous bump 2–5 mm across, often with a central dark spot where the proboscis entered. Itching emerges after 15–30 minutes, lasting several days. Mosquito saliva contains a complex mix of proteins that prevent clotting and modulate the host immune response, which can cause localized swelling, redness, and in sensitized persons, larger wheals or urticaria.
Key differences include:
- Mouthpart structure: Fleas use chewing‑type mandibles; mosquitoes use a needle‑like proboscis.
- Bite pattern: Fleas tend to bite in clusters; mosquitoes bite singly.
- Lesion size and appearance: Flea punctures are smaller with a peripheral halo; mosquito lesions are larger, centrally colored, and lack a halo.
- Onset of symptoms: Flea irritation appears almost immediately; mosquito itching may be delayed.
- Allergic potential: Both can induce hypersensitivity, but flea saliva more often causes papular urticaria in children.
- Disease transmission: Fleas are vectors for bacteria such as Yersinia pestis and parasites like Rickettsia spp.; mosquitoes transmit viruses (e.g., dengue, Zika) and parasites (e.g., Plasmodium spp.).
- Preferred body sites: Fleas favor lower extremities, ankles, and waistline; mosquitoes bite exposed skin, often on arms, legs, and face.
Understanding these distinctions aids in accurate identification, appropriate treatment, and preventive measures tailored to each arthropod.