clove and Respiratory-Syncytial-Virus-Infections

Respiratory syncytial virus is the main cause of acute respiratory infections leading to a considerable morbidity and mortality among under-5 years children. A comprehensive scheme of RSV virus evolution is of great value in implementing effective universal RSV vaccine.. We investigated the clinical spectrum and molecular characteristics of detected RSV over a period of seven years (January 2011 to June 2017) in Antananarivo, the capital city of Madagascar.. 671 nasopharyngeal samples taken from children aged less than 5 years suffered from ARI were screened for RSV by real-time PCR. Clinical data were retrieved from case report forms. Genotype identification was performed by reverse-transcription PCR and sequencing of the second hyper variable region (HVR2) of the G glycoprotein.. Amongst samples tested, 292 (43.5 %) were found positive for RSV. RSV A predominated during the study period which accounted for 62.3 % (182/292) of positive samples while RSV B represented 37.0 % (108/292). Phylogenetic analyses identified NA1 and ON1 genotypes among RSV A. Though NA1 widespread from 2011 to 2013, ON1 became prevalent during the following years. Among RSV B, THB, CB1 and BA9 genotypes were detected. A co-circulation of THB and CB1 strains occurred during the 2011 season that was substituted by the BA9 from 2012. Malagasy ON1 strains carried some characteristic amino acid substitutions that distinguish them from the worldwide ON1 strains. By analyzing clinical spectrum, ON1 and BA genotypes seemed to prevail in mild infections compared to NA1.. Results obtained here will have its implication in predicting temporal evolution of RSV at the local level. Considering the insularity of the country, information obtained should help in comparative analysis with global RSV strains to optimize vaccine efficacy.

Topics: Child; Genetic Variation; Genotype; Humans; Infant; Madagascar; Molecular Epidemiology; Phylogeny; Respiratory Syncytial Virus Infections; Respiratory Syncytial Virus, Human

Influenza and respiratory syncytial virus (RSV) infections are responsible for substantial global morbidity and mortality in young children and elderly individuals. Estimates of the burden of influenza- and RSV-associated hospitalization are limited in Africa.. We conducted hospital-based surveillance for laboratory-confirmed influenza- and RSV-associated severe acute respiratory illness (SARI) among patients of any age at one hospital and a retrospective review of SARI hospitalizations in five hospitals situated in Antananarivo during 2011-2016. We estimated age-specific rates (per 100 000 population) of influenza- and RSV-associated SARI hospitalizations for the Antananarivo region and then extrapolated these rates to the national level.. Overall, the mean annual national number of influenza-associated SARI hospitalizations for all age groups was 6609 (95% CI: 5381-7835-rate: 30.0; 95% CI: 24.4-35.6), 4468 (95% CI: 3796-5102-rate: 127.6; 95% CI: 108.4-145.7), 2141 (95% CI: 1585-2734-rate: 11.6; 95% CI: 8.6-14.8), and 339 (95% CI: 224-459-rate: 50.0; 95% CI: 36.3-74.4) among individuals aged <5, ≥5, and ≥65 years, respectively. For these same age groups, the mean annual number of RSV-associated SARI hospitalizations was 11 768 (95% CI: 10 553-12 997-rate: 53.4; 95% CI: 47.9-59.0), 11 299 (95% CI: 10 350-12 214-rate: 322.7; 95% CI: 295.6-348.8), 469 (95% CI: 203-783-rate: 2.5;95% CI: 1.1-4.2), and 36 (95% CI: 0-84-rate: 5.8; 0.0-13.5), respectively.. The burden of influenza- and RSV-associated SARI hospitalization was high among children aged <5 years. These first estimates for Madagascar will enable government to make informed evidence-based decisions when allocating scarce resources and planning intervention strategies to limit the impact and spread of these viruses.

Topics: Acute Disease; Adolescent; Adult; Aged; Child; Child, Preschool; Cost of Illness; Female; Hospitalization; Humans; Infant; Influenza, Human; Madagascar; Male; Middle Aged; Respiratory Syncytial Virus Infections; Retrospective Studies; Risk Factors; Young Adult

Respiratory syncytial virus (RSV) is one of the most common respiratory pathogens. Immoderate inflammation plays a great role in causing RSV-induced diseases. In the present study, watsonianone A, isolated from the fruit of Rhodomyrtus tomentosa (Ait.) Hassk, was found to show a good inhibitory effect on RSV-induced NO production, with a half-maximal inhibitory concentration of 37.2 ± 1.6 μM. Enzyme-linked immunosorbent assay and fluorescence quantitative polymerase chain reaction analyses indicated that watsonianone A markedly reduced both mRNA and protein levels of tumor necrosis factor α, interleukin 6, and monocyte chemoattractant protein 1 in RSV-infected RAW264.7 cells. Mechanistically, watsonianone A inhibited nuclear factor κB (NF-κB) activation by suppressing IκBα phosphorylation. Further analysis revealed that watsonianone A activated the thioredoxin system and decreased intracellular reactive oxygen species (ROS) levels, which are closely associated with NF-κB activation in RSV-infected cells. These results reveal that watsonianone A can attenuate RSV-induced inflammation via the suppression of ROS-sensitive inflammatory signaling.

Topics: Cyclohexanones; Fruit; Humans; I-kappa B Proteins; Interleukin-6; Myrtaceae; NF-kappa B; Plant Extracts; Reactive Oxygen Species; Respiratory Syncytial Virus Infections; Respiratory Syncytial Viruses; Tumor Necrosis Factor-alpha

In Madagascar, very little is known about the etiology and prevalence of acute respiratory infections (ARIs) in a rural tropical area. Recent data are needed to determine the viral and atypical bacterial etiologies in children with defined clinical manifestations of ARIs.. During one year, we conducted a prospective study on ARIs in children between 2 to 59 months in the community hospital of Ampasimanjeva, located in the south-east of Madagascar. Respiratory samples were analyzed by multiplex real-time RT-PCR, including 18 viruses and 2 atypical bacteria. The various episodes of ARI were grouped into four clinical manifestations with well-documented diagnosis: "Community Acquired Pneumonia"(CAP, group I), "Other acute lower respiratory infections (Other ALRIs, group II)", "Upper respiratory tract infections with cough (URTIs with cough, group III)"and "Upper respiratory tract infections without cough (URTIs without cough, group IV)".. 295 children were included in the study between February 2010 and February 2011. Viruses and/or atypical bacteria respiratory pathogens were detected in 74.6% of samples, the rate of co-infection was 27.3%. Human rhinovirus (HRV; 20.5%), metapneumovirus (HMPV A/B, 13.8%), coronaviruses (HCoV, 12.5%), parainfluenza virus (HPIV, 11.8%) and respiratory syncytial virus A and B (RSV A/B, 11.8%) were the most detected. HRV was predominantly single detected (23.8%) in all the clinical groups while HMPV A/B (23.9%) was mainly related to CAP (group I), HPIV (17.3%) to the "Other ALRIs" (group II), RSV A/B (19.5%) predominated in the group "URTIs with cough" (group III) and Adenovirus (HAdV, 17.8%) was mainly detected in the "without cough" (group IV).. This study describes for the first time the etiology of respiratory infections in febrile children under 5 years in a malaria rural area of Madagascar and highlights the role of respiratory viruses in a well clinically defined population of ARIs.

Topics: Acute Disease; Bacteria; Bacterial Infections; Child, Preschool; Coinfection; Community-Acquired Infections; Cough; Fever; Humans; Madagascar; Paramyxoviridae Infections; Polymerase Chain Reaction; Prevalence; Prospective Studies; Respiratory Syncytial Virus Infections; Respiratory Tract Infections; Rural Population; Seasons; Tropical Climate; Virus Diseases; Viruses