Large-scale HFMD epidemics caused by Coxsackievirus A16 in Bangalore, India during 2013 and 2015.

Hand foot and mouth disease (HFMD) is a relatively unreported disease in India. This study was undertaken to characterize the enterovirus type/s associated with two unexpectedly-massive epidemics that occurred in Bangalore, India in 2013 and 2015. Stool samples of 229 children with HFMD living in Northern and Southern areas of Bangalore were tested by RT-PCR; 189 (82.5%) were enterovirus positive. The Indian CV-A16 strains exhibited 98-99% sequence identity with those reported in France and China in the 5' untranslated region. BLAST and phylogenetic analyses of complete genomes of representative Indian isolates revealed that the 2015 epidemic was predominated by an inter-species recombinant between CV-A16 and coxsackievirus B5. The 2013 epidemic was primarily caused by nonrecombinant strains. The CV-A16 strains circulated in India since 2007 and phylogeographic analyses indicated imported cases in France and China. In conclusion, CV-A16-associated HFMD epidemics should be recognized as an emerging public health problem in India.

Non-polio enterovirus association with persistent diarrhea in children as revealed by a follow-up study of an Indian cohort during the first two years of life.

BACKGROUND: We recently reported significant association of non-polio enteroviruses (NPEVs) with acute diarrhea in children. Persistent diarrhea (PD) remains a major cause of morbidity and mortality in infants below two years of age in developing countries. Understanding age-dependent frequency and duration of NPEV infections is important to determine their association with persistent diarrhea and disease burden. OBJECTIVES: A cohort of 140 infants was followed for 6 months to 2 years of age to determine the frequency, duration, and association with PD of NPEV infections in comparison with rotavirus and other agents. STUDY DESIGN: Stool samples were collected every 14 days, and diarrheal episodes and their duration were recorded. Enteroviruses were characterized by RT-PCR and VP1 gene sequence analysis, rotavirus by electropherotyping, and other agents by PCR. RESULTS: Of 4545 samples, negative for oral polio vaccine strains, 3907 (85.96%) and 638 (14.04%) were NPEV-negative and NPEV-positive, respectively, representing 403 (8.87%) infection episodes. About 68% of NPEV infections occurred during the first year with every child having at least one episode lasting between four days and four months. Approximately 38% and 22% of total diarrheal episodes were positive for NPEV and RV, respectively. While about 18% of NPEV infection episodes were associated with diarrhea, 6% being persistent, 13% of total diarrheal episodes were persistent involving infections by monotype NPEV strains or sequential infections by multiple strains and other agents. CONCLUSIONS: This is the first report revealing NPEVs as the single most frequently and persistently detected viral pathogen in every PD episode.