An antivector vaccine protects against a lethal vector-borne pathogen

Area of Science:

• Veterinary immunology
• Parasitology
• Infectious diseases

Background:

• Vaccines targeting disease vectors like ticks can prevent vector-borne diseases.
• Rhipicephalus appendiculatus is a significant tick vector.
• Tick-borne encephalitis virus (TBEV) is a major public health concern.

Purpose of the Study:

• To evaluate the efficacy of a novel anti-tick vaccine based on Rhipicephalus appendiculatus cement protein (64TRP) against TBEV transmission in mice.
• To assess the vaccine's dual action on tick feeding and survival.
• To compare the vaccine's performance against a commercial TBEV vaccine and an anti-tick vaccine (TickGARD).

Main Methods:

• Mice were immunized with a 64TRP vaccine derived from Rhipicephalus appendiculatus.
• Vaccinated and control mice were infested with infected Ixodes ricinus ticks carrying TBEV.
• Key parameters measured included virus transmission rates, host support of transmission, and host survival after challenge.

Main Results:

• A single dose of the 64TRP vaccine conferred significant protection against lethal TBEV challenge by infected ticks.
• The 64TRP vaccine demonstrated a dual action: impairing tick blood feeding and causing tick mortality.
• The vaccine's protective effect was comparable to a commercial TBEV vaccine, with superior transmission-blocking capabilities.

Conclusions:

• The 64TRP anti-tick vaccine shows significant potential for controlling TBEV by interfering with pathogen transmission.
• The vaccine's efficacy is mediated by a local immune response at the tick-feeding site, leading to impaired feeding and tick death.
• This approach offers a promising strategy for managing vector-borne diseases by targeting the vector itself.