title: 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.
abstract: 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.
  
  
  OBJECTIVE
  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.
  
  
  METHODS
  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.
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India. Electronic address: cdr@mcbl.iisc.ernet.in.
authors: Durga C
authors: DC
authors: Rao
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India.
authors: Harikrishna
authors: H
authors: Reddy
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India.
authors: K
authors: K
authors: Sudheendra
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India.
authors: A
authors: A
authors: Raghavendra
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India.
authors: Vembuli
authors: V
authors: Varadharaj
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India.
authors: Surekha
authors: S
authors: Edula
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India.
authors: Ramya
authors: R
authors: Goparaju
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India.
authors: Bharath
authors: B
authors: Ratnakar
authors: Indian Statistical Institute, Kolkata, India; Georgia Regents University, Augusta, GA, USA.
authors: Arni S R
authors: AS
authors: Srinivasa Rao
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India; MS Ramaiah Teaching Hospital, Bangalore, India; Agadi Hospital, Bangalore, India.
authors: Padmanabha P
authors: PP
authors: Maiya
authors: Department of Microbiology & Cell Biology, Indian Institute of Science, Bangalore, India; RMV Hospital, Bangalore, India; Arpita Clinic, Bangalore, India.
authors: M
authors: M
authors: Ananda Babu
mesh_terms: D002675:Child, Preschool; D015331:Cohort Studies; D003967:Diarrhea / Q000821:virology*; D004770:Enterovirus; D004769:Enterovirus Infections / Q000821:virology*; D005243:Feces / Q000821:virology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007194:India; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008969:Molecular Sequence Data; D012367:RNA, Viral / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D015678:Viral Structural Proteins / Q000235:genetics
chemical_list: D012367:RNA, Viral; D015678:Viral Structural Proteins
keywords: Acute diarrhea; Enterovirus (EV); Non-polio enterovirus (NPEV); Persistent diarrhea (PD); Rotavirus