ABSTRACT
Dengue is the most prevalent arboviral disease affecting humans, with tropical and subtropical regions having the highest risk of dengue virus infections. The clinical symptoms often range from mild fever to fever with hemorrhagic manifestations and shock. Since 2010, India has been witnessing a marked increase in the number of dengue virus serotype 1 (DENV-1) infections, apart from those of serotypes 2 (DENV-2) and 3 (DENV-3). The present study was undertaken to understand the circulating genotypes of DENV-1 in South West India, by sequencing the envelope gene of DENV-1 samples representative of the 2014-2015 time period. The extracted RNAs from dengue NS1 antigen ELISA-positive samples, archived at the APEX Referral Laboratory for Arboviruses (National Vector Borne Disease Control Programme, Manipal Centre for Virus Research), were used for the study. The currently circulating genotypes of DENV-1 identified from the study area belong to genotypes V and I. Multicentric laboratory-based studies analyzing the envelope gene of all dengue serotypes are required from endemic countries like India.
Subject(s)
Dengue Virus/classification , Dengue Virus/genetics , Dengue/epidemiology , Dengue/virology , Genotype , Dengue/history , History, 21st Century , Humans , India/epidemiology , Phylogeny , RNA, Viral , Sequence Analysis, DNA , Viral Envelope Proteins/geneticsABSTRACT
Acute viral respiratory infections (AVRI) are a leading cause of morbidity and mortality among all age groups globally. Except for Influenza virus and Respiratory Syncytial virus, mostly viral aetiology of AVRI remains undiagnosed. Lately, human coronaviruses (HCoVs) have emerged as an important aetiology of AVRI. A laboratory based retrospective cross sectional study was conducted in which respiratory samples (throat swabs) of patients (n = 864), with Influenza negative SARI, of all age groups between Jan 2011-Dec 2012 were tested for HCoVs including MERS-CoV using Conventional and real time PCR assays. The prevalence of HCoV among SARI cases was 1.04% (9/864) [95% CI: 0.36-1.72]. Of these four (44.44%) were identified as HCoV OC43, three (33.33%) as HCoV NL63 and two (22.22%) as HCoV 229E. No HCoV HKU1 was detected. The samples were also negative for SARS-CoV and MERS-CoV. The results of this study documents low prevalence of human coronaviruses in SARI cases in south western India and the absence of highly pathogenic human coronaviruses. As the study included only SARI cases the prevalence reported could be an under estimate when it is extrapolated to community.
