How many people have been infected by a tick bite? - briefly
Approximately 30 000 people are diagnosed with tick‑borne infections each year in the United States, while worldwide estimates range from several hundred thousand to over a million cases annually.
How many people have been infected by a tick bite? - in detail
Tick bites transmit a range of pathogens that affect millions of individuals each year. The World Health Organization estimates that more than 1 billion people are exposed to tick bites annually, and at least 10 million develop a clinically recognized infection.
Key tick‑borne diseases and their reported annual incidence:
- Lyme disease: ≈ 300 000–400 000 cases in the United States, 65 000–85 000 in Europe, and several thousand in Asia.
- Rocky Mountain spotted fever: ≈ 5 000–6 000 cases in the United States; sporadic reports in Central and South America.
- Tick‑borne encephalitis: ≈ 12 000–13 000 cases in Europe and Asia combined.
- Babesiosis: ≈ 2 000–2 500 cases in the United States; limited data elsewhere.
- Anaplasmosis and ehrlichiosis: ≈ 4 000–5 000 cases in the United States annually.
- Other infections (e.g., rickettsial diseases, relapsing fever, Crimean‑Congo hemorrhagic fever): collectively contribute several thousand additional cases worldwide.
Summing reported figures yields a conservative estimate of 10–12 million confirmed tick‑borne infections per year. The true burden is higher because many cases remain undiagnosed or unreported, particularly in regions with limited surveillance infrastructure.
Data derive from national public‑health agencies, the Centers for Disease Control and Prevention, the European Centre for Disease Prevention and Control, and peer‑reviewed epidemiological studies. Variability in diagnostic criteria, reporting practices, and geographic coverage creates uncertainty, but the available evidence confirms a substantial global impact of tick‑related disease transmission.