Recent development of enterovirus A vaccine candidates for the prevention of hand, foot, and mouth disease

ABSTRACT

Introduction: Hand, foot, and mouth disease (HFMD) is a childhood illness commonly caused by enterovirus A. Enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) are the most commonly identified viruses associated with HFMD. Recently, outbreaks caused by different enterovirus A including CV-A6 and CV-A10 are increasing. Being available now to protect against EV-A71 infection, inactivated EV-A71 vaccines cannot prevent coxsackievirus infections, thus limiting their general application in controlling HFMD. Multivalent HFMD vaccines are suggested to have broad cross-neutralizing responses against these emerging enteroviruses.

Areas covered: We discuss the recent development of enterovirus A vaccines including the inactivated whole-virion vaccine and virus-like particle vaccine candidates and review the information of neutralization epitopes of these viruses.

Expert commentary: Evaluation of the efficacy and safety of the coxsackievirus vaccine and the multivalent HFMD vaccine candidates in clinical trials is urgently required. Epitopic analysis showed that common immunodominant sites exist across these enteroviruses. However, variations of amino acid residues in these regions limit the induction of cross-neutralization antibodies, and therefore, a multivalent HFMD vaccine is required for broad protection against HFMD. With the inclusion of major circulating viruses in the development of multivalent HFMD vaccines, an increase in the success in HFMD control is anticipated.

KEYWORDS:

• Enterovirus A
• hand, foot, and mouth diseases
• inactivated whole-virion vaccine
• virus-like particle vaccine
• neutralization epitope

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.

Additional information

Funding

This work was supported by the Ministry of Science and Technology [MOST 104-2320-B-400-022-MY2], the National Health Research Institutes [05A1-IVPP11-014 & 07A1-IVPP36–014], and the Taipei Medical University-Wan Fang Hospital research program [106-WF-EVA-09], Taiwan.