Modeling tick vaccines: a key tool to improve protection efficacy

ABSTRACT

Introduction: The development of more effective vaccines for the control of tick infestations and pathogen transmission is essential for prevention and control of tick-borne diseases worldwide. Recently, the application of omics technologies has advanced the identification of tick protective antigens. However, other factors such as vaccine formulation and implementation need to be addressed, and tick vaccine modeling will contribute to improve the efficacy of vaccination strategies.

Areas covered: In this review, we summarized current information on tick vaccine correlates of protection and modeling, and proposed new approaches to improve vaccine evaluation and implementation using as a proof-of-concept the Hyalomma marginatum-Crimean-Congo hemorrhagic fever virus model due to its high mortality rate and potentially growing impact on human health.

Expert opinion: Vaccines are required as an effective and environmentally sound intervention for the control of tick-borne diseases affecting human and animal health worldwide. Despite recent advances in the identification of candidate tick protective antigens, research on vaccine formulation and implementation need to be addressed to improve tick vaccine control efficacy. As shown here, modeling of the vaccination strategies against ticks and transmitted pathogens will contribute to vaccine development by guiding the selection of appropriate antigen combinations, target hosts, and vaccination time schedule.

KEYWORDS:

• Tick
• tick-borne pathogen
• vaccine
• model
• correlates of protection
• antibodies
• crimean-Congo hemorrhagic fever

Article Highlights

• Ticks and tick-borne pathogens constitute a growing burden for human and animal health worldwide.

• Vaccines are the most effective and environmentally sound interventions for the control of tick infestations and tick-borne diseases.

• Despite recent advances in the discovery of new candidate protective antigens, research on vaccine formulation and implementation need to be addressed to improve tick vaccine control efficacy.

• Modeling of vaccination against ticks and pathogens together with the prevalence of both vectors and transmitted pathogens will contribute to vaccine development.

• Modeling guides the selection of appropriate antigen combinations, target hosts, and vaccination time schedule.

• Using Crimean-Congo hemorrhagic fever as a proof-of-concept we showed that vaccines combining tick and virus-derived antigens to target both tick infestations and virus infection and transmission is the most effective intervention for the control of this disease.

• A vaccine targeting both virus infection/transmission and tick infestations will likely be based on combined pathogen-derived and tick-derived protective antigens.

Declaration of Interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer Disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Supplementary Material

The supplementary data for this article can be accessed here.

Additional information

Funding

This work has been partially supported by the Spanish program CYTED, project number 118RT0542 and The Sealy and Smith Foundation, Galveston, TX, USA, grant number 84477.