What harm do ticks cause? - briefly
Ticks transmit bacterial, viral, and protozoan pathogens such as Lyme disease, Rocky Mountain spotted fever, and babesiosis, and they can cause local skin irritation, allergic reactions, and, in rare cases, neurologic complications. Their bite also introduces toxins that may lead to fever, fatigue, and joint pain.
What harm do ticks cause? - in detail
Ticks transmit a range of pathogens that affect humans and animals. Bacterial agents include Borrelia burgdorferi, the cause of Lyme disease, and Anaplasma phagocytophilum, responsible for human granulocytic anaplasmosis. Viral infections such as tick‑borne encephalitis virus and Crimean‑Congo hemorrhagic fever virus can lead to severe neurological impairment or hemorrhagic fever. Protozoan parasites, notably Babesia microti, produce babesiosis, a malaria‑like illness that may result in hemolytic anemia.
The clinical consequences of these infections are diverse:
- Dermatologic manifestations: erythema migrans, a expanding rash typical of early Lyme disease.
- Neurological involvement: meningitis, facial palsy, peripheral neuropathy, and, in rare cases, encephalitis.
- Cardiac effects: Lyme carditis can cause atrioventricular block and arrhythmias.
- Hematologic disorders: hemolytic anemia from babesiosis, thrombocytopenia, and leukopenia in anaplasmosis.
- Renal complications: acute kidney injury may develop during severe Lyme disease or hemorrhagic fever.
- Systemic symptoms: fever, fatigue, muscle aches, joint inflammation, and, occasionally, chronic arthritic disease.
Beyond infectious disease, tick bites can induce allergic reactions, ranging from localized swelling to anaphylaxis in sensitized individuals. Mechanical injury from prolonged attachment may lead to skin ulceration or secondary bacterial infection.
Preventive measures—prompt removal of attached ticks, use of repellents, and habitat management—reduce exposure risk and limit the burden of these health threats.