RESUMEN
Understanding the factors driving SARS-CoV-2 infection progression and severity is complex due to the dynamic nature of human physiology. Therefore, we aimed to explore the severity risk indicators of SARS-CoV-2 through demographic data, clinical manifestations, and the profile of laboratory parameters. The study included 175 patients either hospitalized at King Abdulaziz Medical City-Riyadh or placed in quarantine at designated hotels in Riyadh, Saudi Arabia, from June 2020 to April 2021. Hospitalized patients were followed up through the first week of admission. Demographic data, clinical presentations, and laboratory results were retrieved from electronic patient records. Our results revealed that older age (OR: 1.1, CI: [1.1-1.12]; p < 0.0001), male gender (OR: 2.26, CI: [1.0-5.1]; p = 0.047), and blood urea nitrogen level (OR: 2.56, CI: [1.07-6.12]; p = 0.034) were potential predictors of severity level. In conclusion, the study showed that apart from laboratory parameters, age and gender could potentially predict the severity of SARS-CoV-2 infection in the early stages. To our knowledge, this study is the first in Saudi Arabia to explore the longitudinal profile of laboratory parameters among risk factors, shedding light on SARS-CoV-2 infection progression parameters.
RESUMEN
Respiratory syncytial virus is a leading cause of acute respiratory tract infection (ARI) in children worldwide. Limited information is available on molecular epidemiology of respiratory syncytial virus (RSV) from Saudi Arabia. An attempt was made to identify and characterize RSV strains in nasopharyngeal aspirates collected from hospitalized symptomatic ARI pediatric patients with <5 years of age from Riyadh, Saudi Arabia during 2016. All the samples (n = 100) were tested for RSV by real time PCR. The RSV strains were characterized by sequencing of the second hypervariable region of G protein gene. The study sequences along with the previously reported strains from Saudi Arabia were assessed for mutational, glycosylation, phylogenetic, selection pressure and entropy analyses. Fifty percent of the nasopharyngeal aspirates were positive for RSV. The RSVA (72%) predominated as compared to RSVB (24%) during the study. The study RSVA strains (n = 29) clustered into NA1 and ON1 genotypes whereas all the RSVB sequences (n = 5) were in BA genotype by phylogenetic analysis. Interestingly, 97% of RSVA sequences (n =28) clustered into ON1 genotype with 72 bp duplication in the G protein gene. Numerous mutations, variable N-/O-glycosylation sites and purifying selections were observed in the ON1 genotype. Positive selection with high entropy value was observed for three codons in ON1 (247, 262 and 274 amino acids) indicating higher probability of variations at these positions. Our study shows the progressive emergence and predominance of the ON1 genotype in Riyadh, Saudi Arabia during 2008-16. ON1 genotype almost replaced the previously circulating RSVA strains in this region during this period. Contribution of host genetic and immune factors towards disease severity of the ON1 genotype needs to be investigated in future studies. RSV surveillance in future elaborate investigations are needed in this region to understand its disease burden, evolutionary trajectory and circulation dynamics warranting steps towards vaccine development.
Asunto(s)
Técnicas de Genotipaje/métodos , Mutación , Infecciones por Virus Sincitial Respiratorio/virología , Virus Sincitial Respiratorio Humano/clasificación , Preescolar , Entropía , Evolución Molecular , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Filogenia , Infecciones por Virus Sincitial Respiratorio/epidemiología , Virus Sincitial Respiratorio Humano/genética , Arabia Saudita/epidemiología , Selección GenéticaRESUMEN
Respiratory syncytial virus (RSV) is a major pathogen of acute respiratory tract infection (ARI) in different geographical regions including Saudi Arabia. Numerous hospital-based investigations have revealed the RSV prevalence between 0.2-54% in the paediatric population with ARI/ALRI from Saudi Arabia during 1991-2015. Maximum RSV infections occurred in children less than 1 year of age (51-97%) and male children (51-69%) were more commonly affected than females (31-49%). RSV infections are reported mostly during winter season suggesting seasonal distribution of the virus. Other respiratory viruses reported from this region are adenovirus, influenza, parainfluenza, human metapneumovirus and rhinovirus including many mixed infections. A few studies have reported the phylogenetic analysis of the circulating strains of RSV. These studies have revealed that circulating group A-RSV Saudi strains belonged to NA1 and ON1 genotypes and group B-RSV viruses clustered in the BA genotype. Molecular characterization of the Saudi strains was further carried out by mutational, selection pressure and glycosylation site analyses. We have compiled all the eighteen studies of RSV infection from Saudi Arabia in the form of this review and concluded that detailed comprehensive surveillance of RSV and other viruses in community and hospital settings is required. Information on the molecular characterization of currently circulating strains of RSV will contribute towards better understanding of the epidemiology and evolutionary dynamics of this viral pathogen. Moreover, the determination of the genetic composition of circulating RSV strains will be important during evaluation of initial vaccine trials.