Enteroviruses Associated with Hand Foot and Mouth Disease in Navi Mumbai, Maharashtra, India in 2022.

An outbreak of Hand Foot and Mouth Disease (HFMD) which occurred in August-September, 2022 in Navi Mumbai, India was prospectively investigated, to delineate the clinical manifestations and identify the etiological agent. Molecular characterization at ICMR-National Institute of Virology (NIV), Mumbai unit reported 69 (88.5%) cases out of 78 clinically diagnosed HFMD cases positive for enteroviruses. Thirty-nine (56.5%) children were positive for CVA6, 11 (15.9%) for CVA16, and one for CVA4 (1.4%). One case of co-infection (CVA16, CVA6) was reported. Fourteen (17.9%) cases had recurrent disease in the same season. CVA6 was associated with unusual extension of the rash beyond the conventional areas of hands, feet, and mouth, with involvement of body areas including face, axillae and trunk. Whole genome sequencing classified CVA6 as group D3 and CVA16 isolates as group B1c. Co-infection and recurrence of disease with atypical symptoms observed in this study highlight the need for continued vigilance of the evolutionary clinical characteristics of the enteroviruses causing HFMD.