Location: Tick and Biting Fly Research
Title: Exploring the use of anti-tick vaccine as tool for integrated eradication of the cattle fever tick, Rhipicephalus (Boophilus) annulatus Authors
|Estrada-Pena, Agustin -|
|Almazan, Consuelo -|
|Messenger, Matthew -|
|Ellis, Dee -|
|Perez De Leon, Adalberto|
Submitted to: Vaccine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 25, 2012
Publication Date: August 17, 2012
Citation: Miller, R., Estrada-Pena, A., Almazan, C., Yeater, K.M., Messenger, M., Ellis, D., Perez De Leon, A.A. 2012. Exploring the use of anti-tick vaccine as tool for integrated eradication of the cattle fever tick, Rhipicephalus (Boophilus) annulatus. Vaccine. 30(38):5682-5687. Interpretive Summary: Successful efforts by the Cattle Fever Tick Eradication Program (CFTEP) have prevented the re-introduction of cattle fever ticks into the U.S since 1943. Eradication is maintained through continuous, systematic inspection of cattle within the permanent quarantine zone (PQZ) for cattle fever ticks in south Texas along the Mexican border. The detection of one tick in a herd of cattle signals an outbreak and triggers laws to eliminate the infestation, which involves current practices that can be economically and operationally challenging for producers. We tested the concept of using an anti-tick vaccine to control and prevent infestations with the cattle fever tick, Rhipicephalus (Boophilus) annulatus, for considerable time without pesticide treatment. Control with the anti-tick vaccine based on the antigen Bm86 that is commercially available outside the U.S. was 99.9 and 91.4% immediately after the standard inoculation protocol and at 5.5 months after the initial inoculation, respectively. Computer modeling was applied to assess the usefulness of integrating an anti-tick vaccine for sustainable eradication. Modeling results predicted that control greater than 40% would eradicate R. annulatus from the northeastern half of the CFTEP without pesticide application. Integrating the use of a Bm86-based vaccine with other eradication practices could prevent R. annulatus infestations indefinitely. Adapting such integrated practices would incentivize producers to maintain cattle on pasture thereby avoiding the need to vacate infested premises. It is hypothesized that the integrated approach to eradication incorporating an anti-tick vaccine would reduce pesticide use, realize efficiencies for the CFTEP, and allow producers to raise cattle in sectors of the PQZ that have been under quarantine on and off for the past 68 years.
Technical Abstract: Bovine babesiosis, also known as cattle fever, is a tick-borne protozoal disease foreign to the United States. It was eradicated by eliminating the vector species, Rhipicephalus (Boophilus) annulatus and R. (B.) microplus, through the efforts of the Cattle Fever Tick Eradication Program (CFTEP), with the exception of a permanent quarantine zone (PQZ) in south Texas along the border with Mexico. Keeping the U.S. free of cattle fever ticks in a sustainable manner is a critical national agricultural biosecurity issue. The efficacy of a Bm86-based anti-tick vaccine commercialized outside of the U.S. was evaluated against a strain of R. annulatus originated from an outbreak in Texas. Vaccination controlled 99.9 and 91.4% of the ticks 8 weeks and 5.5 months after the initial vaccination protocol, respectively. Computer modeling of habitat suitability within the PQZ typically at risk of re-infestation with R. annulatus from Mexico predicted that at a level of control greater than 40% eradication would be maintained indefinitely. Efficacy and computer modeling data indicate that the integration of vaccination, using a Bm86-based anti-tick vaccine, with other eradication practices within the northwestern half of the PQZ could incentivize producers to maintain cattle on pasture thereby avoiding the need to vacate infested premises. Implementing this epidemiologically proactive strategy offers the opportunity to prevent R. annulatus outbreaks in the U.S., which would represent a significant shift in the way the CFTEP operates.