The disease burden of respiratory syncytial virus in older adults

Purpose of reviewTo highlight the respiratory syncytial virus (RSV) disease burden and the current developments and challenges in RSV prevention for older adults ≥60 years through analysis of RSV epidemiology and the effectiveness of emerging vaccines.Recent findingsIn industrialized countries, RSV incidence rates and hospitalization rates among older adults stand at 600.7 cases per 100,000 person-years and 157 hospitalizations per 100,000 person-years, respectively. Yet, accurately determining RSV morbidity and mortality in older adults is challenging, thus resulting in substantially under-estimating the disease burden. The in-hospital fatality rates vary substantially with age and geographies, sometimes reaching up to 9.1% in developing countries. Two promising RSV vaccines for the elderly have been approved, showcasing efficacies of up to 94.1%, signifying considerable advancement in RSV prevention. However, concerns over potential side effects remain. SummaryRSV is associated with a significant burden in older adults. While the landscape of RSV prevention in older adults is promising with the licensure of vaccines from two companies, current trial data underscore the need for additional studies. Addressing the real-world effectiveness of these vaccines, understanding potential rare side effects, and ensuring broad inclusivity in future trials are crucial steps to maximize their potential benefits.<br/

Phylogenetic variability of Human Metapneumovirus in patients with acute respiratory infections in Cameroon, 2011–2014

International audienceBACKGROUND: Identified in 2001, Human Metapneumovirus (HMPV) is a Pneumovirus associated with acute lower and upper respiratory infections in all age groups and especially in newborns, elderly and immunocompromised subjects. Data are still limited in sub-Saharan African countries genetic characterization of this respiratory virus. This study reports the genetic variability of HMPV strains in Cameroonian children for 3 consecutive epidemic seasons (September 2011-October 2014).METHODS: A prospective surveillance was conducted to identify inpatient and outpatient children less than 15 years with respiratory symptoms ≤5 days. The nasopharyngeal samples were tested for HMPV using a multiplex polymerase chain reaction. Viral distribution and demographic data were analyzed statistically. Positive samples for HMPV were amplified by semi-nested polymerize chain reaction and then partially sequenced at the G gene. Phylogenetic analyzes were performed on the partial nucleotide and protein sequences of the G gene.RESULTS: From September 2011 to October 2014, 822 children under 15 years were enrolled in the study. HMPV was identified in each of 3.9% (32/822) of children. HMPV were detected throughout the year. HMPV-A (73.3%; 11/15) was predominant compared to HMPV-B (26.7; 4/15). Cameroonian HMPV strains are grouped among the members of genotype A2b (for HMPV-A), B1 and B2 (for HMPV-B).CONCLUSION: This study suggests that about 4% of ARI recorded in children in Cameroon are caused by HMPV. The present study is also the first report on the genetic variability of the G gene of HMPV strains in the region. Although this work partially fills gaps for some information, additional studies are required to clarify the molecular epidemiology and evolutionary pattern of HMPV in sub-Saharan Africa in general and more particularly in Cameroon

Phylogenic analysis of human bocavirus detected in children with acute respiratory infection in Yaounde, Cameroon

International audienceOBJECTIVE: Human Bocavirus (HBoV) was first identified in 2005 and has been shown to be a common cause of respiratory infections and gastroenteritis in children. In a recent study, we found that 10.7% of children with acute respiratory infections (ARI) were infected by HBoV. Genetic characterization of this virus remains unknown in Central Africa, particularly in Cameroon Leeding us to evaluate the molecular characteristics of HBoV strains in Cameroonian children with ARI.RESULTS: Phylogenetic analysis of partial HBoV VP1/2 sequences showed a low level of nucleotide variation and the circulation of HBoV genotype 1 (HBoV-1) only. Three clades were obtained, two clustering with each of the reference strains ST1 and ST2, and a third group consisting of only Cameroon strains. By comparing with the Swedish reference sequences, ST1 and ST2, Cameroon sequences showed nucleotide and amino acid similarities of respectively 97.36-100% and 98.35-100%. These results could help improve strategies for monitoring and control of respiratory infections in Cameroon

Prevalence and genetic diversity of respiratory viruses in Cameroon

Contexte : Les infections respiratoires aiguës (ARI) sont reconnues comme une cause importante de morbidité, de mortalité et d'hospitalisation chez les enfants dans les pays en développement. Le virus respiratoire syncytial humain (HRSV) est l’agent étiologique principal de maladie sévère des voies respiratoires basses chez les nourrissons, les jeunes enfants et les personnes âgées. Identifié en 2001, le Metapneumovirus humain (HMPV) est un nouveau paramyxovirus. Les études ont montré la cocirculation des sous groupes de ces deux virus avec la domination de l’un des sous groupes selon les zones géographiques et selon les années. Les données restent cependant limitées dans les pays de l’Afrique subsaharienne, sur la prévalence, la saisonnalité et la caractérisation génétique de ces deux virus respiratoires. Au Cameroun, ces deux virus ont été décrits seulement une seule fois (5,7 et 5% pour HRSV et HMPV respectivement) chez des patients présentant des syndromes grippaux en 2012. Objectif : Cette étude rapporte la prévalence, la saisonnalité et la variabilité génétique des souches HRSV et HMPV chez des enfants camerounais pendant 3 saisons épidémiques consécutives (de Septembre 2011 à Octobre 2014). Par ailleurs, la diversité génétique d’autres virus respiratoires détectés au cours de ce travail est présentée comme objectif secondaire.Méthodes : Une surveillance prospective a été menée pour identifier les enfants hospitalisés et ambulatoires âgés de moins de 15 ans présentant des symptômes respiratoires ≤ 5 jours. Les échantillons nasopharyngés ont été testés pour 17 virus respiratoires en utilisant une réaction multiplex de polymérisation en chaîne. La distribution virale et les données démographiques ont été analysées statistiquement. Les échantillons positifs du HRSV et HMPV ont été amplifiés par polymérisation en chaine semi nichée puis séquencés partiellement au niveau du gène G. Des analyses phylogénétiques ont été effectuées sur les séquences nucléotidiques et protéiques partielles du gène G.Résultats : De septembre 2011 à octobre 2014, 822 enfants âgés de moins de 15 ans ont été inscrits dans l’étude. Au moins un virus a été identifié chez chacun des 72,6% (597/822) d'enfants, dont 31,7% (189/597) étaient des codétections; 28,5% (226/822) étaient positifs pour l'adénovirus humain, 21,4% (176/822) pour le virus Influenza, 15,5% (127.822) pour le rhinovirus/entérovirus, 9,4% (77/822) pour le bocavirus, 9% (74/822) pour le HRSV, 8,2% (67/822) pour les coronavirus humain, 6,2% (50/822) pour le parainfluenzavirus humain et 3,9% (32/822) pour le HMPV. L’infection HRSV était plus fréquente chez les enfants de moins de 2 ans (70,3% ; 52/74) et chez les participants hospitalisés (70,3% ; 52/74). Alors que le HRSV a montré un profil saisonnier avec une circulation de septembre à décembre, des cas sporadiques de HMPV ont été détectés tout au long de l'année. HRSV-A (19,1%, 9/47) et HRSV-B (17% ; 8/47) ont été observés relativement à la même fréquence avec (63,8% ; 30/47) de cas en codétection HRSV-A/HRSV-B alors que HMPV-A (71,4% ; 10/14) était majoritaire comparé à HMPV-B (28,6 ; 4/14). L'analyse phylogénétique a révélé que les souches HRSV de l’étude sont groupées au sein du sous groupe NA-1 (pour HRSV-A) et BA-9 (pour HRSV-B). Les souches HMPV camerounaises sont groupés parmi les membres du génotype A2b (pour HMPV-A), B1 et B2 (pour HMPV-B).Conclusion : Cette étude suggère qu’environ 70% des ARI enregistrés chez des enfants au Cameroun sont causés par des virus. La présente étude est également le premier rapport sur la variabilité génétique du gène G des souches de HRSV et HMPV dans la région. Bien que ce travail comble partiellement certaines lacunes d’informations, des études supplémentaires sont requises pour une clarification de l’épidémiologie moléculaire et du mode d’évolution des virus respiratoires présents en Afrique subsaharienne en général et plus singulièrement au Cameroun.Background: Acute respiratory infections (ARI) are recognized as an important cause of morbidity, mortality and hospitalization among children in developing countries. Human respiratory syncytial virus (HRSV) is the main cause of severe lower respiratory tract disease in infants, young children and the elderly. Identified in 2001, Human Metapneumovirus (HMPV) is a new paramyxovirus. Studies have shown the co-circulation of the subgroups of these two viruses with domination of one of the sub-groups according to the geographical zones and according of years. These two viruses encode two major surface glycoproteins, the highly conserved fusion F protein and the highly variable attachment G protein. Data are still limited in sub-Saharan African countries on prevalence, seasonality and genetic characterization of these two respiratory viruses. In Cameroon, these two viruses have been described only once (5.7 and 5% for HRSV and HMPV respectively) in patients with influenza-like illness in 2012.Objective: This study reports the prevalence, seasonality and the genetic variability of HRSV and HMPV strains in Cameroonian children for 3 consecutive epidemic seasons (September 2011-October 2014). Moreover, the genetic diversity of other respiratory viruses detected during this work is presented as a secondary objective.Methods: A prospective surveillance was conducted to identify inpatient and outpatient children less than 15 years with respiratory symptoms ≤ 5 days. The nasopharyngeal samples were tested for 17 respiratory viruses using a multiplex polymerase chain reaction. Viral distribution and demographic data were analyzed statistically. Positive samples for HRSV and HMPV were amplified by semi-nested polymerize chain reaction and then partially sequenced at the G gene. Phylogenetic analyzes were performed on the partial nucleotide and protein sequences of the G gene.Results: From September 2011 to October 2014, 822 children under 15 years were enrolled in the study. At least one virus was identified in each of 72.6% (577/822) of children, 31.7% (189/597) of whom were co-detections; 28.5% (226/822) were positive for human adenovirus, 21.4% (176/822) for influenza virus, 15.5% (127.822) for rhinovirus/enterovirus, 9.4% (77/822) for bocavirus, 9% (74/822) for HRSV, 8.2% (67/822) for human coronavirus, 6.2% (50/822) for human parainfluenzavirus, and 3.9% (32/822) for HMPV. HRSV infection was more frequent in children under 2 years (70.3%, 52/74) and hospitalized participants (70.3%, 52/74). While HRSV showed a seasonal pattern with circulation from September to December, sporadic cases of HMPV were detected throughout the year. HRSV-A (19.1%, 9/47) and HRSV-B (17%; 8/47) were observed relatively at the same frequency with (63.8%, 30/47) codetections of HRSV-A/HRSV-B. HMPV-A (71.4%; 10/14) was predominant compared to HMPV-B (28.6; 4/14). Phylogenetic analysis revealed that the HRSV strains of the study are grouped within subgroup NA-1 (for HRSV-A) and BA-9 (for HRSV-B). Cameroonian HMPV strains are grouped among the members of genotype A2b (for HMPV-A), B1 and B2 (for HMPV-B).Conclusion: This study suggests that about 70% of ARI recorded in children in Cameroon are caused by viruses. The present study is also the first report on the genetic variability of the G gene of HRSV and HMPV strains in the region. Although this work partially fills gaps for some information, additional studies are required to clarify the molecular epidemiology and evolutionary pattern of respiratory viruses in sub-Saharan Africa in general and more particularly in Cameroon

Prévalence et diversité génétique des virus respiratoires au Cameroun

Background: Acute respiratory infections (ARI) are recognized as an important cause of morbidity, mortality and hospitalization among children in developing countries. Human respiratory syncytial virus (HRSV) is the main cause of severe lower respiratory tract disease in infants, young children and the elderly. Identified in 2001, Human Metapneumovirus (HMPV) is a new paramyxovirus. Studies have shown the co-circulation of the subgroups of these two viruses with domination of one of the sub-groups according to the geographical zones and according of years. These two viruses encode two major surface glycoproteins, the highly conserved fusion F protein and the highly variable attachment G protein. Data are still limited in sub-Saharan African countries on prevalence, seasonality and genetic characterization of these two respiratory viruses. In Cameroon, these two viruses have been described only once (5.7 and 5% for HRSV and HMPV respectively) in patients with influenza-like illness in 2012.Objective: This study reports the prevalence, seasonality and the genetic variability of HRSV and HMPV strains in Cameroonian children for 3 consecutive epidemic seasons (September 2011-October 2014). Moreover, the genetic diversity of other respiratory viruses detected during this work is presented as a secondary objective.Methods: A prospective surveillance was conducted to identify inpatient and outpatient children less than 15 years with respiratory symptoms ≤ 5 days. The nasopharyngeal samples were tested for 17 respiratory viruses using a multiplex polymerase chain reaction. Viral distribution and demographic data were analyzed statistically. Positive samples for HRSV and HMPV were amplified by semi-nested polymerize chain reaction and then partially sequenced at the G gene. Phylogenetic analyzes were performed on the partial nucleotide and protein sequences of the G gene.Results: From September 2011 to October 2014, 822 children under 15 years were enrolled in the study. At least one virus was identified in each of 72.6% (577/822) of children, 31.7% (189/597) of whom were co-detections; 28.5% (226/822) were positive for human adenovirus, 21.4% (176/822) for influenza virus, 15.5% (127.822) for rhinovirus/enterovirus, 9.4% (77/822) for bocavirus, 9% (74/822) for HRSV, 8.2% (67/822) for human coronavirus, 6.2% (50/822) for human parainfluenzavirus, and 3.9% (32/822) for HMPV. HRSV infection was more frequent in children under 2 years (70.3%, 52/74) and hospitalized participants (70.3%, 52/74). While HRSV showed a seasonal pattern with circulation from September to December, sporadic cases of HMPV were detected throughout the year. HRSV-A (19.1%, 9/47) and HRSV-B (17%; 8/47) were observed relatively at the same frequency with (63.8%, 30/47) codetections of HRSV-A/HRSV-B. HMPV-A (71.4%; 10/14) was predominant compared to HMPV-B (28.6; 4/14). Phylogenetic analysis revealed that the HRSV strains of the study are grouped within subgroup NA-1 (for HRSV-A) and BA-9 (for HRSV-B). Cameroonian HMPV strains are grouped among the members of genotype A2b (for HMPV-A), B1 and B2 (for HMPV-B).Conclusion: This study suggests that about 70% of ARI recorded in children in Cameroon are caused by viruses. The present study is also the first report on the genetic variability of the G gene of HRSV and HMPV strains in the region. Although this work partially fills gaps for some information, additional studies are required to clarify the molecular epidemiology and evolutionary pattern of respiratory viruses in sub-Saharan Africa in general and more particularly in Cameroon.Contexte : Les infections respiratoires aiguës (ARI) sont reconnues comme une cause importante de morbidité, de mortalité et d'hospitalisation chez les enfants dans les pays en développement. Le virus respiratoire syncytial humain (HRSV) est l’agent étiologique principal de maladie sévère des voies respiratoires basses chez les nourrissons, les jeunes enfants et les personnes âgées. Identifié en 2001, le Metapneumovirus humain (HMPV) est un nouveau paramyxovirus. Les études ont montré la cocirculation des sous groupes de ces deux virus avec la domination de l’un des sous groupes selon les zones géographiques et selon les années. Les données restent cependant limitées dans les pays de l’Afrique subsaharienne, sur la prévalence, la saisonnalité et la caractérisation génétique de ces deux virus respiratoires. Au Cameroun, ces deux virus ont été décrits seulement une seule fois (5,7 et 5% pour HRSV et HMPV respectivement) chez des patients présentant des syndromes grippaux en 2012. Objectif : Cette étude rapporte la prévalence, la saisonnalité et la variabilité génétique des souches HRSV et HMPV chez des enfants camerounais pendant 3 saisons épidémiques consécutives (de Septembre 2011 à Octobre 2014). Par ailleurs, la diversité génétique d’autres virus respiratoires détectés au cours de ce travail est présentée comme objectif secondaire.Méthodes : Une surveillance prospective a été menée pour identifier les enfants hospitalisés et ambulatoires âgés de moins de 15 ans présentant des symptômes respiratoires ≤ 5 jours. Les échantillons nasopharyngés ont été testés pour 17 virus respiratoires en utilisant une réaction multiplex de polymérisation en chaîne. La distribution virale et les données démographiques ont été analysées statistiquement. Les échantillons positifs du HRSV et HMPV ont été amplifiés par polymérisation en chaine semi nichée puis séquencés partiellement au niveau du gène G. Des analyses phylogénétiques ont été effectuées sur les séquences nucléotidiques et protéiques partielles du gène G.Résultats : De septembre 2011 à octobre 2014, 822 enfants âgés de moins de 15 ans ont été inscrits dans l’étude. Au moins un virus a été identifié chez chacun des 72,6% (597/822) d'enfants, dont 31,7% (189/597) étaient des codétections; 28,5% (226/822) étaient positifs pour l'adénovirus humain, 21,4% (176/822) pour le virus Influenza, 15,5% (127.822) pour le rhinovirus/entérovirus, 9,4% (77/822) pour le bocavirus, 9% (74/822) pour le HRSV, 8,2% (67/822) pour les coronavirus humain, 6,2% (50/822) pour le parainfluenzavirus humain et 3,9% (32/822) pour le HMPV. L’infection HRSV était plus fréquente chez les enfants de moins de 2 ans (70,3% ; 52/74) et chez les participants hospitalisés (70,3% ; 52/74). Alors que le HRSV a montré un profil saisonnier avec une circulation de septembre à décembre, des cas sporadiques de HMPV ont été détectés tout au long de l'année. HRSV-A (19,1%, 9/47) et HRSV-B (17% ; 8/47) ont été observés relativement à la même fréquence avec (63,8% ; 30/47) de cas en codétection HRSV-A/HRSV-B alors que HMPV-A (71,4% ; 10/14) était majoritaire comparé à HMPV-B (28,6 ; 4/14). L'analyse phylogénétique a révélé que les souches HRSV de l’étude sont groupées au sein du sous groupe NA-1 (pour HRSV-A) et BA-9 (pour HRSV-B). Les souches HMPV camerounaises sont groupés parmi les membres du génotype A2b (pour HMPV-A), B1 et B2 (pour HMPV-B).Conclusion : Cette étude suggère qu’environ 70% des ARI enregistrés chez des enfants au Cameroun sont causés par des virus. La présente étude est également le premier rapport sur la variabilité génétique du gène G des souches de HRSV et HMPV dans la région. Bien que ce travail comble partiellement certaines lacunes d’informations, des études supplémentaires sont requises pour une clarification de l’épidémiologie moléculaire et du mode d’évolution des virus respiratoires présents en Afrique subsaharienne en général et plus singulièrement au Cameroun

Prevalence of respiratory viruses using polymerase chain reaction in children with wheezing, a systematic review and meta-analysis.

IntroductionWheezing is a major problem in children, and respiratory viruses are often believed to be the causative agent. While molecular detection tools enable identification of respiratory viruses in wheezing children, it remains unclear if and how these viruses are associated with wheezing. The objective of this systematic review is to clarify the prevalence of different respiratory viruses in children with wheezing.MethodsWe performed an electronic in Pubmed and Global Index Medicus on 01 July 2019 and manual search. We performed search of studies that have detected common respiratory viruses in children ≤18 years with wheezing. We included only studies using polymerase chain reaction (PCR) assays. Study data were extracted and the quality of articles assessed. We conducted sensitivity, subgroup, publication bias, and heterogeneity analyses using a random effects model.ResultsThe systematic review included 33 studies. Rhinovirus, with a prevalence of 35.6% (95% CI 24.6-47.3, I2 98.4%), and respiratory syncytial virus, at 31.0% (95% CI 19.9-43.3, I2 96.4%), were the most common viruses detected. The prevalence of other respiratory viruses was as follows: human bocavirus 8.1% (95% CI 5.3-11.3, I2 84.6%), human adenovirus 7.7% (95% CI 2.6-15.0, I2 91.0%), influenza virus6.5% (95% CI 2.2-12.6, I2 92.4%), human metapneumovirus5.8% (95% CI 3.4-8.8, I2 89.0%), enterovirus 4.3% (95% CI 0.1-12.9, I2 96.2%), human parainfluenza virus 3.8% (95% CI 1.5-6.9, I2 79.1%), and human coronavirus 2.2% (95% CI 0.6-4.4, I2 79.4%).ConclusionsOur results suggest that rhinovirus and respiratory syncytial virus may contribute to the etiology of wheezing in children. While the clinical implications of molecular detection of respiratory viruses remains an interesting question, this study helps to illuminate the potential of role respiratory viruses in pediatric wheezing.Review registrationPROSPERO, CRD42018115128

Coronavirus in water environments: Occurrence, persistence and concentration methods - A scoping review

Coronaviruses (CoV) are a large family of viruses causing a spectrum of disease ranging from the common cold to more severe diseases as Middle East Respiratory Syndrome (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS-CoV). The recent outbreak of coronavirus disease 2019 (COVID-19) has become a public health emergency worldwide. SARS-CoV-2, the virus responsible for COVID-19, is spread by human-to-human transmission via droplets or direct contact. However, since SARS-CoV-2 (as well as other coronaviruses) has been found in the fecal samples and anal swabs of some patients, the possibility of fecal-oral (including waterborne) transmission need to be investigated and clarified. This scoping review was conducted to summarize research data on CoV in water environments. A literature survey was conducted using the electronic databases PubMed, EMBASE, and Web Science Core Collection. This comprehensive research yielded more than 3000 records, but only 12 met the criteria and were included and discussed in this review. In detail, the review captured relevant studies investigating three main areas: 1) CoV persistence/survival in waters; 2) CoV occurrence in water environments; 3) methods for recovery of CoV from waters. The data available suggest that: i) CoV seems to have a low stability in the environment and is very sensitive to oxidants, like chlorine; ii) CoV appears to be inactivated significantly faster in water than non-enveloped human enteric viruses with known waterborne transmission; iii) temperature is an important factor influencing viral survival (the titer of infectious virus declines more rapidly at 23°C–25 °C than at 4 °C); iv) there is no current evidence that human coronaviruses are present in surface or ground waters or are transmitted through contaminated drinking-water; v) further research is needed to adapt to enveloped viruses the methods commonly used for sampling and concentration of enteric, non enveloped viruses from water environments. The evidence-based knowledge reported in this paper is useful to support risk analysis processes within the drinking and wastewater chain (i.e., water and sanitation safety planning) to protect human health from exposure to coronavirus through water

Association of early viral lower respiratory infections and subsequent development of atopy, a systematic review and meta-analysis of cohort studies.

IntroductionExisting evidence on the relationship between childhood lower respiratory tract infections (LRTI) and the subsequent atopy development is controversial. We aimed to investigate an association between viral LRTI at 2 years.MethodsWe conducted a search at Embase, Pubmed, Web of Science, and Global Index Medicus. We collected data from the included articles. We estimated the odds ratio and the 95% confidence intervals with a random effect model. We determined factors associated with atopy development after childhood LRTI using univariate and multivariate meta-regression analyses. We recorded this systematic review at PROSPERO with the number CRD42018116955.ResultsWe included 24 studies. There was no relationship between viral LRTI at ConclusionThese results suggest that there is no association between viral LRTI at < 5 years and the majority of categories of atopy studied during this work. These results, however, are not confirmed for the remaining categories of atopy and more particularly those diagnosed by serum tests. There is a real need to develop more accurate atopy diagnostic tools