Molecular epidemiology of enteroviruses associated with hand, foot, and mouth disease in South India from 2015 to 2017

Abstract

Hand, foot, and mouth disease (HFMD) is a common childhood infection caused by human enteroviruses and is clinically characterised by fever with vesicular rash on the hands, feet, and mouth. While enterovirus A71 (EV-A71) and coxsackievirus A16 (CVA16) were the major etiological agents of HFMD in India earlier, the data on recently circulating enteroviruses associated with HFMD are sparse. Here, we describe the molecular epidemiology of enteroviruses associated with HFMD in South India from 2015 to 2017. We used archived enterovirus real-time reverse transcription (RT) PCR-positive vesicle swab and/or throat swab specimens from clinically suspected HFMD cases collected from four secondary-care hospitals in South India between July 2015 and December 2017. PCR amplification and sequencing were done based on the 5’VP1, 3’VP1, VP2, or 5´NCR regions to identify enterovirus types. Genetic diversity among enteroviruses was inferred by phylogenetic analysis. Of the 107 enterovirus RNA real-time RT-PCR-positive HFMD cases, 69 (64%) were typed as CVA6, 16 (15%) were CVA16, and one (1%) was CVA10, whereas in 21 (20%) cases, the virus was not typeable by any of the methods used in the study. The majority of HFMD cases (89, 83%) were in children less than five years old, while 11 (10.3%) were in adults. 5’VP1 yielded the maximum number of enteroviruses genotyped, and phylogenetic analysis showed that the CVA6 strains belonged to subclade D3, while the subclades of CVA16 and CVA10 were B1c and D, respectively. The predominant etiological agent of HFMD in South India during 2015-2017 was CVA6, followed by CVA16 and CVA10. Supplementary Information The online version contains supplementary material available at 10.1007/s00705-022-05561-0.

Emergence of Recombinant Subclade D3/Y in Coxsackievirus A6 Strains in Hand-Foot-and-Mouth Disease (HFMD) Outbreak in India, 2022

“…Multiple enterovirus serotypes were found to circulate simultaneously in HFMD patients from Bhubaneswar, Odisha, in 2009, southern and eastern India in 2009–2010 [ 22 ], and northern Kerala in 2015–2016. CV-A6 was the leading cause of HFMD in India from 2015 to 2017, followed by CV-A16 and CV-A10 [ 28 ]. Co-circulation of CV-A6 and CV-A16 was reported to cause HFMD in Mumbai in May–June 2018 [ 29 ].…”

Molecular Epidemiology and Evolution of Coxsackievirus A14

“…In recent years, the prevalence of enteroviruses dominated by non-EV-A71 and non-CVA16 has gradually increased at home and abroad, and their reports in HFMD cases have increased significantly, such as CVA6, CVA10, and CVA4 [32][33][34][35][36]. Especially in many regions of mainland China, other enteroviruses once surpassed EV-A71 and CVA16 to become the dominant serotype becoming the main pathogen in the pathogenic spectrum of HFMD [37,38].…”

‘Tomato flu’ a new epidemic in India: Virology, epidemiology, and clinical features

“…However, HFMD with EV-A71 is attributed to a more severe disease progression. In a comparative study done among 177 EV-A71 and 64 CV-A16 patients during the enterovirus epidemic in Taiwan, only 6.3% of CV-A16 infections developed into aseptic meningitis [ 14 ]. However, an alarming 32% of EV-A71 cases resulted in aseptic meningitis, encephalitis, polio-like syndrome, encephalomyelitis and fatal pulmonary edema.…”