Detection and molecular characterization of uncommon rotavirus group A genotype G12 among hospitalized children in Chennai.

Arun P, Krishnasami K, Gunasekeran P, Fathima G, Padmanabhan V. Detection and molecular characterization of uncommon rotavirus group A genotype G12 among hospitalized children in Chennai. Turk J Pediatr 2019; 61: 209-216. Human group A (RVAs) possess genetic diversity and often newer RVA strains have been reported frequently with different G and P combinations worldwide. As the disease burden is more common in low income countries including India, monitoring and detection of the circulating strains of rotavirus needs to be monitored to understand the genetic diversity of the strains which evolve over time. This study was an attempt to provide data on rotavirus gastroenteritis prevalence in and around Chennai Tamilnadu-South India during the pre-vaccination era. Stool samples were collected and tested from 401 children less than five years of age admitted to hospitals with acute gastroenteritis. The samples were subjected to amplification for VP7 and VP4 genes by using consensus primers, followed by semi-nested type-specific multiplex PCR. Phylogenetic analysis of VP7 genes of G12 were carried out and the variations between strains isolated globally were documented. Rotavirus was detected in 167 (41.64%) samples and five were found to be the uncommon G12P[6] genotype (2.99%) tested by RT-PCR followed by G1P[8], G9P[4], G9 with P untypable and G3P[8] and combinations of G2G9P[6] and G9G2P[11] with few strains untypable. In this study we highlight the occurrence of uncommon G12P[6] strain of rotavirus infection in the community. Since rotavirus is transmitted through oral-fecal route and monitoring of environmental cleanliness is mandatory to cease the spread of this deadliest viral agent to achieve our MDG-IV. Covering single genotype will have to be modified with respect to the circulating stains.

Isolation & molecular characterization of human parainfluenza virus in Chennai, India.

BACKGROUND & OBJECTIVES: Human parainfluenza virus (HPIV) accounts for a significant proportion of lower respiratory tract infections in children as well as adults. This study was done to detect the presence of different subtypes of HPIV from patients having influenza like illness (ILI). METHODS: Throat and nasal swabs from 232 patients with ILI who were negative for influenza viruses were tested by multiplex reverse transcription polymerase chain reaction(mRT-PCR) for the detection of human parainfluenza virus. All samples were inoculated in rhesus monkey kidney (LLC-MK2) cell line. RESULTS: Of the 232 samples, 26(11.2%) were positive by mRT-PCR and nine (34.6%) showed cytopathic effect with syncytium formation for HPIV and all were HPIV-3 serotype, other serotypes like 1,2,4 were negative. The HPIV-3 strains (HN gene) were sequenced and analysed. Two novel mutations were identified at amino acid residues 295 and 297. INTERPRETATION & CONCLUSIONS: The mRT-PCR assay offers a rapid, sensitive and accurate diagnostic method for detection of HPIV which enables early detection and control. In our study there was a predominance of HPIV among 1-5 yr age group and the school going age group was less affected. Further studies need to be done to characterize HPIV isolated from different parts of the country.