When is the encephalitis tick season? - briefly
The tick species that transmit tick‑borne encephalitis are most active from late spring through early autumn, typically May – September, with peak activity in June to August. Risk diminishes sharply once temperatures drop below 10 °C in the fall.
When is the encephalitis tick season? - in detail
Tick activity that can transmit tick‑borne encephalitis (TBE) begins in early spring when temperatures rise above 7 °C. Nymphs, which are most responsible for human infections, emerge in late April to early May. Adult ticks become active later, from July through September. Consequently, the period of highest risk typically spans May to October, with the peak incidence recorded in June, July, and August in most of Europe.
Regional variations are significant:
- Central Europe (Germany, Austria, Czech Republic, Poland): activity starts in late April; peak cases occur in June–July; risk declines after early October.
- Scandinavia (Sweden, Finland): nymphal activity begins in early May; peak transmission in July–August; season can extend into late October in milder years.
- Baltic states and Russia: earlier onset, sometimes late March; prolonged activity through November in southern zones.
- High‑altitude or mountainous areas: delayed start by 2–4 weeks, shorter overall season.
Factors influencing the length of the season include:
- Ambient temperature – sustained warm days accelerate tick development.
- Humidity – ticks require moisture; dry periods reduce activity.
- Snow cover – early melt advances the start; late snowfall postpones it.
- Climate trends – warmer springs and extended autumns have lengthened the risk window in recent decades.
Preventive measures should be implemented before the first nymphs appear and maintained until the last adult ticks are inactive. Vaccination schedules, personal protective clothing, and regular tick checks are most effective when aligned with the regional onset and peak months outlined above.