High Prevalence of G12 Human Rotaviruses in Children with Gastroenteritis in Myanmar

Abstract

SUMMARY: Human rotavirus samples from 54 children with acute gastroenteritis in Myanmar in 2011 were subjected to reverse transcription-PCR to determine their G and P types. On G typing, G2 (24/54; 44.4z) was found to be the most prevalent, followed by G12 (17/54; 31.5z) and G1 (1/54; 1.9z). Mixed cases with G2 and G12 were found in 12 of the 54 (22.2z) samples. On P typing, P[4] was found to be the most predominant (29/54; 53.7z), followed by P[8] (17/54; 31.5z) and P[6] (4/54; 7.4z). Mixed cases with P[4] and P [8] were detected in 4 of 54 (7.4z) samples. Thus, occurrence of G2 and unusual G12 in high proportions was characteristic of human rotaviruses in Myanmar in this study setting.Human group A rotaviruses are the major pathogens causing acute non-bacterial gastroenteritis in infants and young children worldwide. It has been estimated that rotavirus infections are responsible for the deaths of approximately 400,000 children per year in developing countries (1). Also in developed countries, rotavirus gastroenteritis is associated with severe cases requiring hospitalization. Furthermore, some of central nervous system disorders, including encephalopathy, appear to be related to rotavirus infections. With this background, 2 live rotavirus vaccines have been licensed worldwide and are included in the scheduled immunization programs in many countries.Two rotavirus outer capsid proteins, VP7 and VP4, are independently associated with the G and P types, respectively. A cutoff value of 80z nucleotide sequence identity has been employed for defining distinct G and P types (2). At least 27 G types and 37 P types have been reported to date in mammalian and avian species. In humans, at least 10 G types and 10 P types have been detected. G1 to G4 and G9 are the major G types, with G5, G8, and G12 being the unusual ones, while, P[8] is the most common, followed by P[4], P[6], and P[9]. G1P[8] is the most frequent G and P combination in the rotaviruses isolated from symptomatic humans worldwide (3).Although global surveys on the G and P types of human rotaviruses have been extensively performed, there have been few epidemiological studies on human rotaviruses in Myanmar (4,5). In this study, we characterized human rotaviruses in Myanmar by genotyping the VP7 and VP4 genes, and found a high prevalence of G2 and unusual G12.Stool specimens were collected from children with gastroenteritis in the Defense Services Obstetrics, Gynecology and Children Hospital, Yangon, Myanmar. The ages of children ranged from 2 months to 3 years. Fifty-four rotavirus-positive diarrheal children selected randomly were enrolled in a double-blind, placebocontrolled clinical trial of rotavirus-specific IgY conducted between January 2011 and March 2011 (6). Stool suspensions (10z) were prepared from the stool specimens collected from the 54 children before the start of the trial.For G typing and P typing, rotavirus double-stranded RNAs extracted from the stool suspensions were used as templates for reverse transcription-PCR (RT-PCR) in 2 steps (fi...

Diversity of rotavirus genotypes circulating in children < 5 years of age hospitalized for acute gastroenteritis in India from 2005 to 2016: analysis of temporal and regional genotype variation

“…The G12 genotype was first detected in children with diarrhoea in the Philippines during 1987-1988, and was subsequently reported from Thailand and USA (1998)(1999), and from India in 2003 from the eastern region [30][31][32][33]. In the following years, G12 was reported from other geographical regions of India also [20,34], and from neighbouring countries such as Nepal, Myanmar, Bangladesh, and Sri Lanka [35][36][37][38][39][40][41][42][43]. During 2005 to 2013, studies on rotavirus diarrhoea in hospitalized children from different continents including Asia found that G12 positivity ranged from 10 to 86% of rotavirus gastroenteritis [44].…”