Pattern Of Respiratory Syncytial Virus Research Articles

Changes in the epidemiological patterns of respiratory syncytial virus and human metapneumovirus infection among pediatric patients and their correlation with severe cases: a long-term retrospective study.

We aim to investigate the prevalence of respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) among pediatric patients with acute respiratory tract illness (ARTI) in southern China both pre- and post-COVID-19 pandemic, as well as identify associated risk factors for severe infections. The study conducted a real-time PCR analysis on hospitalized children with ARTI from 2012 to 2023, specifically targeting RSV, hMPV, and other respiratory pathogens. Additionally, demographic data was collected during this analysis. The prevalence of RSV occurs triennially, and likewise, the temporal pattern of hMPV outbreaks mirrors that of RSV. The peak infection rates of RSV and hMPV occurred during and following the implementation of COVID-19 epidemic prevention and control measures. The incidence of RSV infection exhibited bimodal peaks in 2022, while hMPV demonstrated seasonal peaks during the spring, fall, and winter periods post-COVID-19 pandemic. After the COVID-19 outbreak, there has been an upward trend in the proportion of female patients and patients aged one year and older presenting with ARTI, RSV infections, and hMPV infections. Infant (OR = 4.767, 95%CI: [3.888-5.846], p < 0.0001), presence of co-infection (OR = 0.540, 95%CI: [0.404-0.722], p < 0.0001), and existence of comorbidities (OR = 1.582, 95%CI: [1.285-1.949], p < 0.0001) was the risk ratio for the severity of RSV infection. Children infected with hMPV under the age of 1 year (OR = 0.322, 95%CI: [0.180 - 0.575], p < 0.0001), as well as those with comorbidities (OR = 8.809, 95%CI: [4.493 - 17.272], p < 0.0001), have a higher risk of developing severe illness. The changing epidemiological patterns have the potential to lead to widespread severe outbreaks among children, particularly those with underlying medical conditions who may experience more severe symptoms. Conducting surveillance for pneumoviridae viruses in children is an imperative measure to establish a robust foundation for future epidemic prevention and treatment strategies.

Risk factors and circulation pattern of respiratory syncytial virus in children under 2years in Maputo, Mozambique.

Evidence on risk factors for respiratory syncytial virus (RSV) in low-resource settings is limited. In Mozambican children <2y of age with severe acute respiratory infection (SARI), we explored risk factors for RSV, described its seasonal variation and assessed associations between RSV and a life-threatening condition. We retrospectively included participants presenting in 2017-2018 in two hospitals in Maputo. RSV was detected and subtyped using real-time quantitative reverse transcription polymerase chain reaction on nasopharyngeal swabs. We used logistic regression and χ2 tests to assess associations and Spearman's correlation coefficient to assess the correlation between weather measurement and RSV positivity. RSV was detected in 23.1% (n=109) of 472 included children and in 50.0% (20/40) of those <3months old. Being <3months (vs >1y) was associated with RSV (adjusted odds ratio 4.3 [95% confidence interval 2.1-8.5]). RSV status was not associated with experiencing a life-threatening condition. RSV A and B co-circulated during the study period, but one type predominated in each year. In 2017, the RSV positivity rate was correlated with monthly average temperature (r=0.793, p=0.002) and precipitation (r=0.596, p=0.041). In Mozambican children with SARI, RSV was prevalent, especially in neonates. However, RSV was not associated with a life-threatening condition.

Global Seasonal Activities of Respiratory Syncytial Virus Before the Coronavirus Disease 2019 Pandemic: A Systematic Review.

Varied seasonal patterns of respiratory syncytial virus (RSV) have been reported worldwide. We conducted a systematic review on articles identified in PubMed reporting RSV seasonality based on data collected before 1 January 2020. RSV seasonal patterns were examined by geographic location, calendar month, analytic method, and meteorological factors including temperature and absolute humidity. Correlation and regression analyses were conducted to explore the relationship between RSV seasonality and study methods and characteristics of study locations. RSV seasons were reported in 209 articles published in 1973-2023 for 317 locations in 77 countries. Regular RSV seasons were similarly reported in countries in temperate regions, with highly variable seasons identified in subtropical and tropical countries. Longer durations of RSV seasons were associated with a higher daily average mean temperature and daily average mean absolute humidity. The global seasonal patterns of RSV provided important information for optimizing interventions against RSV infection.

The genomic evolutionary dynamics and global circulation patterns of respiratory syncytial virus

Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infection in young children and the second leading cause of infant death worldwide. While global circulation has been extensively studied for respiratory viruses such as seasonal influenza, and more recently also in great detail for SARS-CoV-2, a lack of global multi-annual sampling of complete RSV genomes limits our understanding of RSV molecular epidemiology. Here, we capitalise on the genomic surveillance by the INFORM-RSV study and apply phylodynamic approaches to uncover how selection and neutral epidemiological processes shape RSV diversity. Using complete viral genome sequences, we show similar patterns of site-specific diversifying selection among RSVA and RSVB and recover the imprint of non-neutral epidemic processes on their genealogies. Using a phylogeographic approach, we provide evidence for air travel governing the global patterns of RSVA and RSVB spread, which results in a considerable degree of phylogenetic mixing across countries. Our findings highlight the potential of systematic global RSV genomic surveillance for transforming our understanding of global RSV spread.

Global burden and trends of respiratory syncytial virus infection across different age groups from 1990 to 2019: A systematic analysis of the Global Burden of Disease 2019 Study

ObjectiveUnderstanding the global patterns of respiratory syncytial virus (RSV) is crucial for developing effective prevention and control strategies. MethodsData on RSV-related burden were extracted from the Global Burden of Disease 2019. Joinpoint regression models were used to assess the global temporal trends of RSV and further stratified analyses were conducted according to the Socio-demographic Index (SDI), which is a composite measure of income, education, and total fertility. Age-period-cohort model was used to evaluate age, period, and cohort effects. ResultsIn 2019, the global age-standardized rate of mortality (ASMR) and disability-adjusted life years (ASR-DALYs) of RSV were 4.79/100,000 (95% uncertainty interval [95% UI]: 1.82/100,000-9.32/100,000) and 218.34/100,000 (95% UI: 92.06/100,000-376.80/100,000), respectively. The burden of RSV was higher in men than women. The highest ASMR (10.26/100,000, 3.80/100,000-20.16/100,000) and ASR-DALYs (478.71/100,000, 202.40/100,000-840.85/100,000) were reported in low-SDI region. Although mortality and DALYs rates in all age groups declined globally, the pace of decline was not uniform across age groups. Mortality rate in the elderly over 70 years surpassed that in children under 5 years in 2019. ConclusionThis study highlights the need for targeted interventions to reduce the burden of RSV, particularly in low-SDI region, and among the elderly over 70 years.

Respiratory Syncytial Virus Infections in Young Children Presenting to Primary Care in Catalonia During the COVID-19 Pandemic.

We observed an unusual pattern of respiratory syncytial virus (RSV) in children under 5 years in Catalonia (Spain). We observed a near absence of RSV during winter months and a subsequent surge during the late spring. Primary care electronic health records combined with hospital RSV laboratory confirmation could be used to monitor trends of respiratory pathogens.

Determination of genetic characterization and circulation pattern of Respiratory Syncytial Virus (RSV) in children with a respiratory infection, Tehran, Iran, during 2018-2019

The RSV-associated disease accounts for a significant health burden particularly in infants and young children who need to be hospitalized. Since continuous surveillance of circulating RSV genotypes is crucial worldwide, this study aimed to investigate the genetic diversity of RSV circulating strains causing upper or lower acute respiratory infection. Our attention was geared towards studying the cases hospitalized or outpatient in children younger than 2 years of age in Iran during 2018/2019. In this study, nasopharyngeal swabs collected from 206 children who presented with respiratory infection symptoms, were admitted to the referral pediatric ward of Bahrami children's hospital in Tehran, Iran. RSV-positive samples were detected via Nested RT-PCR. The glycoprotein gene was sequenced, and virus genotypes were confirmed through phylogenetic analysis by the MEGA X program. A total of 74 (35.92%) samples tested positive for RSV. Among them, sequencing was done in 10 specimens from 2018 (RSV-A: RSV-B=4:6) and 19 specimens from 2019 (RSV-A: RSV-B=16:3). According to phylogenetic analysis, all RSV-A strains were assigned as ON1 genotype and RSV-B strains were assigned as BA9 genotype. A new N-glycosylation site in Iranian BA9 and positive selection in ON1 genotype was observed. Phylogenetic characterization of strains in the current study revealed co-circulation of ON1 and BA9 as the only prevalent genotypes of both RSV-A and –B groups.

Investigation of occurrence patterns of respiratory syncytial virus A and B in infected-patients from Cheonan, Korea

BackgroundRespiratory infections caused by viruses affect the lower respiratory tract; these infections are severe in patients with underlying diseases and can even lead to death. Respiratory syncytial virus (RSV), one of the causative agents of respiratory viral infections, is the most common cause of pneumonia and bronchiolitis in children and adults.MethodsRespiratory specimens (nasopharyngeal aspirate, nasal swab, throat swab, etc.), which were sent to the Department of laboratory medicine from January 2012 to December 2018 for detection of respiratory viruses via real time reverse transcription PCR (Real time RT-PCR) were used in this study. RSV detected by real-time RT-PCR were analyzed on the basis of co-infection, sex and age of the patients, and year and month of sample collection.ResultsDuring the study period, we observed that the RSV detection rate was 12.8% (n = 1150/9010); the detection rate of RSV-A (7.1%) was higher than that of RSV-B (5.8%). The detection rate of RSV was the highest at 36.5% in December, and RSV-A and RSV-B were in vogue every year. Co-infection rate of RSVs was the highest in the patients over 80 years of age; RSVs showed the highest Co-infection with Rhinoviruses.ConclusionsDuring the study period, prevalence was different among the two subtypes of RSV, and the average age of RSV-B-positive patients was higher than that of RSV-A. Co-infection rate tended to increase every year. RSVs cause mild as well as severe infections. There are reports of serious clinical progress as RSVs cause overlapping infections with other viruses and increase the risk of secondary bacterial infections. Thus, further research on RSV should be done.

Comparative Seasonal Respiratory Virus Epidemic Timing in Utah

Previous studies have found evidence of viral interference between seasonal respiratory viruses. Using laboratory-confirmed data from a Utah-based healthcare provider, Intermountain Health Care, we analyzed the time-specific patterns of respiratory syncytial virus (RSV), influenza A, influenza B, human metapneumovirus, rhinovirus, and enterovirus circulation from 2004 to 2018, using descriptive methods and wavelet analysis (n = 89,462) on a local level. The results showed that RSV virus dynamics in Utah were the most consistent of any of the viruses studied, and that the other seasonal viruses were generally in synchrony with RSV, except for enterovirus (which mostly occurs late summer to early fall) and influenza A and B during pandemic years.

Respiratory syncytial virus activity and climate parameters during a 12‐year period

The epidemic pattern of respiratory syncytial virus (RSV) infection during long periods and the factors that determine seasonality are not well studied. In order to correlate the RSV epidemic activity with climate parameters, we conducted a retrospective study of children (0-14 year) who were hospitalized because of respiratory tract infection and had an RSV test performed in the major tertiary pediatric hospital of Greece during a 12-year period (2002-2013). Daily data regarding temperature and humidity were obtained from the Hellenic National Meteorological Service. A total of 2030/7516 (27%) children were tested positive for RSV infection. Among RSV positive children 1945/2030 (95.8%) were infants <1 year. A peak of RSV activity was measured in years 2002, 2003, and 2006 (>35% positive). The RSV season in our area spanned from December to April, with higher incidence during January through March. The peak monthly RSV incidence was observed during February with mean temperature 10.34 °C and mean relative humidity 69.16%. Regarding climate conditions, a statistically significant positive correlation was found between monthly RSV activity and mean monthly relative humidity (rho = 0.66, P-value = 0.02), whereas a negative correlation was found with mean monthly temperature (rho = -0.81, P-value = 0.002). However, in the multivariable analysis, only the effect of mean monthly temperature remained statistically significant (IRR = 0.72, 95% CI: 0.68, 0.80). Further understanding of RSV seasonality in different geographic areas would be important in order to timely implement preventing strategies with immunoprophylaxis or future RSV vaccines.

Superinfection between influenza and RSV alternating patterns in San Luis Potosí State, México.

The objective of this paper is to explain through the ecological hypothesis superinfection and competitive interaction between two viral populations and niche (host) availability, the alternating patterns of Respiratory Syncytial Virus (RSV) and influenza observed in a regional hospital in San Luis Potosí State, México using a mathematical model as a methodological tool. The data analyzed consists of community-based and hospital-based Acute Respiratory Infections (ARI) consultations provided by health-care institutions reported to the State Health Service Epidemiology Department from 2003 through 2009.

Examining strain diversity and phylogeography in relation to an unusual epidemic pattern of respiratory syncytial virus (RSV) in a long-term refugee camp in Kenya

BackgroundA recent longitudinal study in the Dadaab refugee camp near the Kenya-Somalia border identified unusual biannual respiratory syncytial virus (RSV) epidemics. We characterized the genetic variability of the associated RSV strains to determine if viral diversity contributed to this unusual epidemic pattern.MethodsFor 336 RSV positive specimens identified from 2007 through 2011 through facility-based surveillance of respiratory illnesses in the camp, 324 (96.4%) were sub-typed by PCR methods, into 201 (62.0%) group A, 118 (36.4%) group B and 5 (1.5%) group A-B co-infections. Partial sequencing of the G gene (coding for the attachment protein) was completed for 290 (89.5%) specimens. These specimens were phylogenetically analyzed together with 1154 contemporaneous strains from 22 countries.ResultsOf the 6 epidemic peaks recorded in the camp over the period, the first and last were predominantly made up of group B strains, while the 4 in between were largely composed of group A strains in a consecutive series of minor followed by major epidemics. The Dadaab group A strains belonged to either genotype GA2 (180, 98.9%) or GA5 (2, < 1%) while all group B strains (108, 100%) belonged to BA genotype. In sequential epidemics, strains within these genotypes appeared to be of two types: those continuing from the preceding epidemics and those newly introduced. Genotype diversity was similar in minor and major epidemics.ConclusionRSV strain diversity in Dadaab was similar to contemporaneous diversity worldwide, suggested both between-epidemic persistence and new introductions, and was unrelated to the unusual epidemic pattern.

Seasonal Patterns of Respiratory Syncytial Virus, Influenza A Virus, Human Metapneumovirus, and Parainfluenza Virus Type 3 Infections on the Basis of Virus Isolation Data between 2004 and 2011 in Yamagata, Japan

Most acute respiratory infections (ARIs) are thought to be associated with respiratory viruses that cause similar symptoms. Therefore, assessment of clinical and epidemiologic features of these viruses is important for diagnosing a viral infection. We collected 13,325 nasopharyngeal specimens from patients with ARIs and isolated the virus using a microplate method involving 7 cell lines between 2004 and 2011 in Yamagata, Japan. We isolated a total of 5,483 viruses. Respiratory syncytial virus (RSV), influenza A virus (FluA), human metapneumovirus (hMPV), and human parainfluenza virus type 3 (hPIV3) showed clear yearly seasonal patterns; generally, RSV infections peaked at the end of the year, FluA infections peaked between January and March, hMPV infections peaked between March and April, and hPIV3 showed seasonal outbreaks between May and July. Further, RSV, hMPV, and hPIV3 were commonly isolated in 12.0-13.1% of specimens from children aged less than 4 years, whereas FluA was isolated in 7.3-8.2% of specimens from school-aged children. A generalized view of seasonality and age distribution, particularly on the basis of longitudinal epidemiological data, will be helpful for medical decision-making, including decisions related to the use of rapid test kits, selection of antiviral treatments, restriction of antibiotic therapy, and implementation of infection control strategies.

Analysis of biennial outbreak pattern of respiratory syncytial virus according to subtype (A and B) in the Zagreb region

The epidemic pattern of respiratory syncytial virus (RSV) in Croatia is biennial. In order to determine if the circulation of different RSV subtypes affects the outbreak cycle, the aim of the present study was to analyze the epidemic pattern of RSV in children in Croatia (Zagreb region) over a period of 3 consecutive years. The study group consisted of 696 inpatients, aged 0-5 years, who were hospitalized with acute respiratory tract infections caused by RSV, in Zagreb, in the period 1 January 2006-31 December 2008. The virus was identified in nasopharyngeal secretions using direct immunofluorescence. The virus subtype was determined on real-time polymerase chain reaction. Of 696 RSV infections identified in children, subtype A virus caused 374 infections, and subtype B, 318. Four patients had a dual RSV infection (subtypes A and B). The period of study was characterized by four epidemic waves of RSV infections: the first, smaller, in the spring of 2006; the second, larger, in December 2006/January 2007; the third in spring 2008, followed by a fourth outbreak beginning in November of 2008. The biennial virus cycles were persistent although the predominant RSV subtype in the first two epidemic waves was subtype B, and in the second two it was subtype A. Over a 3 year period of observation, the biennial RSV cycle in Croatia cannot be explained by a difference in the predominant circulating subtype of RSV. Other unknown factors account for the biennial cycle of RSV epidemics in Croatia.

Do Circulating RSV-Genotypes Affect Established Biennial Epidemic Periodicity in Zagreb Region?

Objective: The biennial epidemic pattern of respiratory syncytial virus (RSV) circulation in Croatia has been preserved and could not be related to climatic factors and the predominant RSV subtypes. The possibility that the circulation of different RSV genotypes affect the outbreak cycle in children in Croatia (Zagreb region) over a period of 3 consecutive years was explored in the paper. Methods: The study group consisted of inpatients, aged 0-10 years, who were hospi- talized with acute respiratory tract infections caused by RSV, in Zagreb, over the period from 1 January 2006 to 31 De- cember 2008. The virus was identified in the nasopharyngeal secretion using direct immunofluorescence method. The virus subtype and genotype was determined by real-time PCR and sequence analysis, respectively. Results: RSV infec- tions identified in 731 children. RSV subtype A caused 399 infections, and subtype B 332. Two subtype A genotypes (NA1 and GA5) and three subtype B genotypes (BA7, BA9 and BA10) were found. During persistent RSV biennial cycles namely four succeeding outbreaks, the new genotype from the previous smaller outbreak persevered into the up- coming larger outbreak. Conclusion: Our molecular-epidemiology study of RSV subtypes and genotypes during calen- dar months demonstrates that the biennial RSV cycle cannot be fully explained by the dynamic of the predominant cir- culating genotype of RSV. Other unknown factors account for the biennial cycle of RSV epidemics in Croatia.).

Molecular detection and genetic variability of human metapneumovirus in Uruguay

Human metapneumovirus (hMPV) has been described as circulating among the Uruguayan population at least since 1998 based on serologic evidence. However, no isolation attempts, molecular detection, or genetic studies have been carried out so far in the country. In the present study, molecular detection of circulating hMPV in children hospitalized with acute respiratory tract infection in Montevideo-Uruguay was carried out by reverse transcription-polymerase chain reaction (RT-PCR) amplification of the hMPV nucleoprotein (N) gene from 217 nasopharyngeal aspirates. Genetic variability analysis of the positive samples was performed by amplification and sequencing of both N and attachment glycoprotein (G) genes. Eighteen of the 217 samples tested positive for hMPV, with tachypnea, chest indrawing, and wheezing being the main clinical symptoms recorded. Phylogenetic analysis of N and G genes showed that Uruguayan samples clustered in genotypes described previously as A2, B1, and B2, with bootstrap values >or=98%. Sublineages A2a and A2b could also be distinguished within the samples that belong to A2. This is the first molecular report on the circulation of hMPV in Uruguay. The pattern of circulation of this virus, analyzed for both N and G genes independently, resembles the complex evolutionary pattern of respiratory syncytial virus (RSV).

Does the viral subtype influence the biennial cycle of respiratory syncytial virus?

BackgroundThe epidemic pattern of respiratory syncytial virus (RSV) is quite different in regions of Europe (biennial epidemics in alternating cycles of approximately 9 and 15 months) than in the Western Hemisphere (annual epidemics). In order to determine if these differences are accounted for by the circulation of different RSV subtypes, we studied the prevalence of RSV subtype A and B strains in Zagreb County from 1 January 2006 to 31 December 2007.ResultsRSV was identified in the nasopharyngeal secretions of 368 inpatients using direct fluorescence assays and/or by virus isolation in cell culture. The subtype of recovered strains was determined by real-time PCR. Of 368 RSV infections identified in children during this interval, subtype A virus caused 94 infections, and subtype B 270. Four patients had a dual RSV infection (subtypes A and B).The period of study was characterized by two epidemic waves of RSV infections-one, smaller, in the spring of 2006 (peaking in March), the second, larger, in December 2006/January 2007 (peaking in January). The predominant subtype in both outbreaks was RSV subtype B. Not until November 2007 did RSV subtype A predominate, while initiating a new outbreak continuing into the following calendar year.ConclusionThough only two calendar years were monitored, we believe that the biennial RSV cycle in Croatia occurs independently of the dominant viral subtype.

DETECTION OF HUMAN METAPNEUMOVIRUS IN NASOPHARYNGEAL ASPIRATES OF BRAZILIAN CHILDREN BY IMMUNOFLUORESCENCE ASSAY

The circulation of human metapneumovirus is related to seasonal patterns of respiratory syncytial virus. The aim of this study was to determine the frequency of hMPV infection diagnosed by indirect immunofluorescence in children attending emergency department and general wards of Hospital Infantil Albert Sabin in Fortaleza, Ceara, northeastern Brazil, during the respiratory syncytial virus season in 2006. The analysis included 389 samples. Antigens of hPMV were detected in 39 samples. DOI: http://dx.doi.org/10.17525/vrr.v13i1-2.17

The biennial cycle of respiratory syncytial virus outbreaks in Croatia

The paper analyses the epidemic pattern of respiratory syncytial virus (RSV) outbreaks in children in Croatia. Over a period of 11 consecutive winter seasons (1994–2005) 3,435 inpatients from Zagreb County aged from infancy to 10 years who were hospitalised with acute respiratory tract infections were tested for RSV-infection. RSV was identified in nasopharyngeal secretions of patients by virus isolation in cell culture and by detection of viral antigen with monoclonal antibodies.In the Zagreb area, RSV outbreaks were proven to vary in a two-year cycle, which was repeated every 23–25 months. This biennial cycle comprised one larger and one smaller season. Climate factors correlated significantly with the number of RSV cases identified only in the large seasons, which suggests that the biennial cycle is likely to continue regardless of meteorological conditions. Knowledge of this biennial pattern should be useful in predicting the onset of RSV outbreaks in Croatia, and would facilitate planning for the prevention and control of RSV infections in the region.

Short report: seasonal pattern of respiratory syncytial virus in a region with a tropical climate in southeastern Brazil.

Among acute respiratory infections (ARIs), respiratory syncytial virus (RSV) is an important pathogen, especially in infants and preschool children. This study focused on RSV epidemiology in a region of southeastern Brazil with a tropical climate. A total of 406 nasopharyngeal secretion samples were taken from children less than five years of age with ARIs. Of these, 114 (28%) were RSV-positive. These samples were found in all age groups, but showed a higher prevalence in newborns. Infection with RSV was identified in 10 of the 12 months of the study period, but the majority (88.5%) of cases occurred from late summer to mid-fall.