How does infection by a subcutaneous tick occur? - briefly
Infection follows attachment of a tick beneath the skin surface, where its mouthparts penetrate the dermis and pathogen‑laden saliva is injected during blood feeding. The introduced microbes spread through the host’s bloodstream, initiating disease.
How does infection by a subcutaneous tick occur? - in detail
A subcutaneous tick attaches to the skin by inserting its hypostome into the epidermis and dermis. The mouthparts create a small canal that remains open for several days, allowing continuous blood ingestion.
During feeding, the tick secretes saliva that contains anticoagulants, immunomodulatory proteins, and, if present, pathogens. These substances are introduced directly into the host’s bloodstream through the feeding canal. Pathogen entry occurs when microorganisms residing in the tick’s salivary glands or midgut are expelled with the saliva and enter the host’s circulatory system.
Key steps in the transmission process:
- Attachment: Tick inserts hypostome and secures itself with cement-like proteins.
- Saliva injection: Salivary glands release a cocktail of bioactive compounds into the host tissue.
- Pathogen release: Bacteria, viruses, or protozoa present in the tick’s saliva are deposited into the host’s blood.
- Establishment: Pathogens multiply and disseminate, leading to clinical infection.
The timing of transmission varies by pathogen. Some bacteria, such as Borrelia burgdorferi (Lyme disease), may be transferred after 24–48 hours of attachment, while others, like Rickettsia spp., can be transmitted within a few hours.
Host factors influencing infection risk include immune status, skin integrity at the bite site, and duration of tick attachment. Prompt removal of the tick, ideally within 12 hours, reduces the likelihood of pathogen transfer.
Prevention strategies focus on avoiding tick exposure, using repellents, conducting regular skin inspections after outdoor activities, and employing proper tick removal techniques to minimize the feeding period.