What is used to vaccinate against ticks? - briefly
There is no vaccine that targets the tick itself; immunization is limited to specific tick‑borne diseases, such as the canine Lyme‑disease vaccine and the human tick‑borne encephalitis vaccine.
What is used to vaccinate against ticks? - in detail
Vaccination against tick infestations relies on recombinant protein preparations derived from tick gut antigens, primarily the Bm86 molecule isolated from Rhipicephalus (Boophilus) microplus. Commercial products such as Gavac® and TickGARD® contain purified Bm86 or its variants and are administered subcutaneously to cattle in two initial doses spaced 2–4 weeks apart, followed by annual boosters. The vaccine induces host antibodies that bind to the tick’s mid‑gut epithelium, impairing blood digestion and reducing reproductive capacity, which translates into lower tick counts and diminished pathogen transmission.
In addition to Bm86‑based formulations, experimental vaccines target salivary proteins (e.g., 64 kDa tick salivary protein, subolesin) and concealed antigens expressed during tick feeding. These candidates are produced in bacterial or yeast expression systems, formulated with adjuvants such as Montanide™ ISA 206 or aluminum hydroxide to enhance immunogenicity. Clinical trials in livestock have demonstrated reductions of 40–80 % in tick burden, depending on the antigen, adjuvant, and challenge species.
For companion animals, canine tick vaccines are not yet available on the market. Research focuses on recombinant antigens that elicit protective immunity against Ixodes spp. and Dermacentor spp. The development pipeline includes multivalent constructs combining Bm86 homologues with salivary gland proteins to broaden species coverage.
Human vaccination against ticks remains experimental. Efforts concentrate on identifying conserved tick antigens that could generate cross‑protective antibodies without inducing autoimmunity. Current strategies involve peptide‑based vaccines and vector‑borne DNA vaccines, still confined to preclinical studies.
Key considerations for vaccine deployment include:
- Cold‑chain requirements: storage at 2–8 °C, protection from light.
- Dosage schedule: primary series followed by annual revaccination.
- Safety profile: minimal local reactions; no systemic adverse events reported in field trials.
- Integration with acaricide programs: vaccines reduce reliance on chemicals, mitigating resistance development.
Overall, recombinant tick antigens, particularly Bm86 and its derivatives, constitute the primary immunological tool for controlling tick infestations in livestock, while research advances toward broader applications in dogs and humans.