How do ticks transmit disease to cats and humans?

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Ticks transmit diseases to cats and humans by acting as disease vectors, carrying pathogens such as bacteria, viruses, and protozoan parasites.1

When a tick feeds on an infected host, it ingests blood containing these pathogens. The pathogens then live and multiply within the tick, often migrating to the tick's salivary glands or other tissues. Because tick saliva contains compounds that block pain, itch, and immune responses, bites often go unnoticed, allowing the tick to feed for an extended period and transmit the pathogens into the host's bloodstream.1

Transmission can occur through several mechanisms:
* Transstadial transmission: Pathogens survive as the tick molts from one life stage to the next (e.g., larva to nymph).1
* Transovarial transmission: Certain pathogens can be passed directly from a female tick to her eggs and subsequent larvae.1

Because ticks frequently feed on multiple host species throughout their lives, they effectively spread these diseases among wildlife, domestic animals, and humans.1