How is the encephalitis tick transmitted? - briefly
The virus is passed to humans when an infected tick attaches and feeds, injecting the pathogen with its saliva. Transmission occurs primarily through bites from nymphal or adult Ixodes ticks during the spring‑summer activity period.
How is the encephalitis tick transmitted? - in detail
The encephalitis‑carrying tick spreads the virus through several biological mechanisms that operate throughout its life cycle. Adult females lay eggs that may already contain the pathogen, allowing the next generation to inherit infection (vertical transmission). After hatching, larvae acquire the virus while feeding on small mammals, such as rodents, which serve as natural reservoirs. The pathogen persists through the molt to the nymph stage (transstadial transmission), enabling nymphs to infect new hosts during their subsequent blood meal. Nymphs and adults frequently bite humans, especially during peak activity periods in spring and early summer, when they quest on vegetation and attach to passing hosts.
Key factors influencing transmission include:
- Host selection: Ticks preferentially feed on competent reservoir species that maintain high viral loads, increasing the probability of acquisition.
- Co‑feeding: Simultaneous feeding of infected and uninfected ticks on the same host facilitates virus exchange without systemic infection of the host.
- Environmental conditions: Warm, humid climates promote tick activity and survival, extending the window for human exposure.
- Behavioral patterns: Humans entering tick‑infested habitats (forests, grasslands) without protective clothing or repellents are at greatest risk.
The virus replicates in the tick’s salivary glands after acquisition, ensuring that during subsequent bites, infectious saliva is injected directly into the host’s skin. This direct inoculation bypasses the skin barrier and initiates infection. Effective prevention therefore targets each stage of the tick’s life cycle and its interaction with hosts.