Rapid detection of hand, foot and mouth disease enterovirus genotypes by multiplex PCR

Abstract

Hand, foot and mouth disease (HFMD) is a pediatric disease associated with infection by enterovirus (EV) genotypes. The major HFMD EV pathogens are enterovirus A71 (EVA71) and coxsackievirus A16 (CVA16); however, recently, coxsackievirus A6 (CVA6) and coxsackievirus A10 (CVA10) have also emerged. EV genotypes cannot be distinguished on clinical grounds and a new methodology for the rapid detection of the four major HFMD EV genotypes is urgently required. In the present study, a multiplex real-time PCR assay was established for the simultaneous detection of CVA6, CVA10, CVA16 and EVA71. The specificity and sensitivity of the assay was determined on a validation panel of clinical samples, comprising cerebrospinal fluid (n = 51), blood (n = 39), feces (n = 58) and throat swabs (n = 29). The results showed that the multiplex real-time PCR exhibited high specificity, no cross-reactivity with other EV genotypes, lower limits of detection for CVA6, CVA10, CVA16 and EVA71 were 4 × 10³, 4 × 10², 5 × 10², and 3 × 10³ copies/μL, respectively and had comparable sensitivity to singleplex assays testing clinical samples. The multiplex real-time PCR methodology established in this study can be employed for the rapid detection of the four most prevalent HFMD-associated EVs, for epidemiologic surveillance of circulating EV genotypes and for assessing treatment responses and vaccine studies.

Keywords: CVA10; CVA16; CVA6; EVA71; Enterovirus; HFMD; Multiplex PCR.