Acute Respiratory Infections Research Articles

Early Warning Systems for Acute Respiratory Infections: Scoping Review of Global Evidence

Background Early warning systems (EWSs) are tools that integrate clinical observations to identify patterns indicating increased risks of clinical deterioration, thus facilitating timely and appropriate interventions. EWSs can mitigate the impact of global infectious diseases by enhancing information exchange, monitoring, and early detection. Objective We aimed to evaluate the effectiveness of EWSs in acute respiratory infections (ARIs) through a scoping review of EWSs developed, described, and implemented for detecting novel, exotic, and re-emerging ARIs. Methods We searched Ovid MEDLINE ALL, Embase, Cochrane Library (Wiley), and CINAHL (Ebsco). The search was conducted on October 03, 2023. Studies that implemented EWSs for the detection of acute respiratory illnesses were included. Covidence was used for citation management, and a modified Critical Appraisal Skills Programme (CASP) checklist was used for quality assessment. Results From 5838 initial articles, 29 met the inclusion criteria for this review. Twelve studies evaluated the use of EWSs within community settings, ranging from rural community reporting networks to urban online participatory surveillance platforms. Five studies focused on EWSs that used data from hospitalization and emergency department visits. These systems leveraged clinical and admission data to effectively detect and manage local outbreaks of respiratory infections. Two studies focused on the effectiveness of existing surveillance systems, assessing their adaptability and responsiveness to emerging threats and how they could be improved based on past performance. Four studies highlighted the integration of machine learning models to improve the predictive accuracy of EWSs. Three studies explored the applications of national EWSs in different health care settings and emphasized their potential in predicting clinical deterioration and facilitating early intervention. Lastly, 3 studies addressed the use of surveillance systems in aged-care facilities, highlighting the unique challenges and needs of monitoring and responding to health threats in environments housing vulnerable populations. The CASP tool revealed that most studies were relevant, reliable, and of high value (score 6: 11/29, 38%; score 5: 9/29, 31%). The common limitations included result generalizability, selection bias, and small sample size for model validation. Conclusions This scoping review confirms the critical role of EWSs in enhancing public health responses to respiratory infections. Although the effectiveness of these systems is evident, challenges related to generalizability and varying methodologies suggest a need for continued innovation and standardization in EWS development.

Nerve Growth Factor and Brain-Derived Neurotrophic Factor in COVID-19

Neurotrophins (NTs) constitute a family of small protein messengers that play a fundamental role in both the central and peripheral nervous systems. In particular, the nerve growth factor (NGF) and the brain-derived neurotrophic factor (BDNF) play a subtle role in the survival, differentiation, and functioning of neuronal populations, as well as in the fine regulation of immune functions. The SARS-CoV-2 infection was characterized by a sequela of symptoms (serious respiratory pathology, inflammatory storm, neurological discomfort, up to the less serious flu-like symptoms), which caused, at the end of 2023, more than 7 million deaths worldwide. Despite the official end of the pandemic, the physical and psychological consequences are currently the object of scientific research, both acute and chronic/long-lasting (Long-COVID-19). Given the multifactorial nature of the outcomes of SARS-CoV-2 infection in adults and children, several studies have investigated the potential involvement of the NGF and BDNF systems in the pathology. This narrative review aims to summarize the most recent evidence on this crucial topic.

Analysis of the incidence of influenza before and after the COVID-19 pandemic in South Korea.

Influenza outbreaks of varying size occur every year, but during the COVID-19 pandemic, many countries experienced influenza at lower levels. However, following the relaxation of COVID-19 prevention measures in 2022, the incidence of influenza began to increase gradually. Thus, this study compared the occurrence of influenza from week 36 of 2017, before the COVID-19 outbreak, until 2023. The analysis was conducted using influenza-like illness occurrence data available from the Korea Disease Control and Prevention Agency infectious disease website. Additionally, to examine the changes in COVID-19 and influenza occurrence during the pandemic, COVID-19 incidence data from 20 January 2020 to 31 August 2023 were obtained from the KDCA Coronavirus Disease 19 homepage. During the COVID-19 pandemic, which corresponds to the 2020/2021 and 2021/2022 influenza seasons, there was no seasonal influenza epidemic, and the incidence rates were below the usual outbreak levels. However, in the 2022/2023 season, when the spread of COVID-19 had eased, a seasonal pattern similar to that observed before the COVID-19 pandemic was noted. Furthermore, correlation analysis between the rates of influenza-like illness and COVID-19 incidence showed no significant correlation during the entire period. However, a significant correlation emerged in 2023 (r = 0.393, p <0.05). These results suggest that influenza was suppressed during the COVID-19 pandemic but returned to typical seasonal patterns after the COVID-19 prevention policies were eased. The positive correlation observed between the incidences of COVID-19 and influenza in 2023 indicates that COVID-19, no longer a novel pandemic-causing infectious disease, may have transitioned to an endemic pattern similar to seasonal influenza.

Landscape of respiratory syncytial virus.

Respiratory syncytial virus (RSV) is an enveloped, negative-sense, single-stranded RNA virus of the Orthopneumovirusgenus of the Pneumoviridae family in the order Mononegavirales. RSV can cause acute upper and lower respiratory tract infections, sometimes with extrapulmonary complications. The disease burden of RSV infection is enormous, mainly affecting infants and older adults aged 75 years or above. Currently, treatment options for RSV are largely supportive. Prevention strategies remain a critical focus, with efforts centered on vaccine development and the use of prophylactic monoclonal antibodies. To date, three RSV vaccines have been approved for active immunization among individuals aged 60 and above. For children who are not eligible for these vaccines, passive immunization is recommended. A newly approved prophylactic monoclonal antibody, Nirsevimab, which offers enhanced neutralizing activity and an extended half-life, provides exceptional protection for high-risk infants and young children. This review provides a comprehensive and detailed exploration of RSV's virology, immunology, pathogenesis, epidemiology, clinical manifestations, treatment options, and prevention strategies.

Prospective clinical surveillance for severe acute respiratory illness and COVID-19 vaccine effectiveness in Kenyan hospitals during the COVID-19 pandemic.

There are limited data from sub-Saharan Africa describing the demographic characteristics, clinical features and outcome of patients admitted to public hospitals with severe acute respiratory infections during the COVID-19 pandemic. We conducted a prospective longitudinal hospital-based sentinel surveillance between May 2020 and December 2022 at 16 public hospitals in Kenya. All patients aged above 18 years admitted to adult medical wards in the participating hospitals were included. We collected data on demographic and clinical characteristics, SARS-CoV-2 infection and COVID-19 vaccination status and, admission episode outcomes. We determined COVID-19 vaccine effectiveness (VE) against admission with SARS-CoV-2 positive severe acute respiratory illness (SARI) (i.e., COVID-19) andprogression to inpatient mortality among patients admitted with SARI, using a test-negative case control design. Of the 52,636 patients included in the study, 17,950 (34.1%) were admitted with SARI. The median age was 50 years. Patients were equally distributed across sexes. Pneumonia was the most common diagnosis at discharge. Hypertension, Human Immunodeficiency Virus (HIV) infection and Diabetes Mellitus were the most common chronic comorbidities. SARS-CoV-2 test results were positive in 2,364 (27.9%) of the 8,471 patients that underwent testing. After adjusting for age, sex and presence of a chronic comorbidity, SARI patients were more likely to progress to inpatient mortality compared to non-SARI patients regardless of their SARS-CoV-2 infection status (adjusted odds ratio (aOR) for SARI and SARS-CoV-2 negative patients 1.22, 95% CI 1.10-1.37; and aOR for SARI and SARS-CoV-2 positive patients 1.32, 95% CI 1.24-1.40). After adjusting for age, sex and presence of a chronic comorbidity, COVID-19 VE against progression to inpatient mortality following admission with SARI for those with a confirmed vaccination status was 0.59 (95% CI 0.27-0.77). We have provided a comprehensive description of the demographic and clinical pattern of admissions with SARI in Kenyan hospitals during the COVID-19 pandemic period as well as the COVID-19 VE for these patients. These data were useful in providing situational awareness during the first three years of the pandemic in Kenya and informing national response measures.

Genetic characterization of influenza B virus and oseltamivir resistance in pediatric patients with acute respiratory infections: a cross-sectional study.

Influenza virus neuraminidase inhibitors (NAIs) drug usage can result in NAI resistance, especially in children and individuals with weakened immune systems. The aim of the present study was to identify NAI-resistant variants of IBV and to introduce probable novel mutations, phylogenetic study, and its epitope mapping based on NA gene in patients from Shiraz, Iran. A cross-sectional study was conducted between 2017 and 2018 on symptomatic children. A real-time PCR was run for IBV screening. Then, making use of direct sequencing, amplified 1401 bases of NA gene and phylogenetic tree reconstructed. Epitopes were predicted using ABCpred server. From among a total of 235 specimens, 9.7% were identified with IBV infection. Of them, sequence of NA gene for 17 isolates were analyzed. Phylogenetic analysis showed that 15 isolates belonged to Yamagata clade 3 Wisconsin/01-like subclade and 2 were related to Victoria clade 1 Brisbane/60-like subclade (Vic-1A-2). NA gene sequence analysis showed a total of 52 substitutions in which 27 were for BVic and 37 were for BYam isolates and 19 were novel substitutions. Only one substitution (S198N) was found in NA active site and T49M, I120V, N198S, N219K, S295R, D320K N340D, E358K, D384G, and D463N were found as probable resistance variants to NAIs. Epitope mapping showed some major differences in our isolates NA gene. Present study was one of the rare comprehensive studies conducted in Shiraz/Iran on IBV resistant associated variants to NAIs. We reported 11.7% mutation in NA active site and some probable NAIs resistant mutations. Epitope mapping confirmed major changes in NA gene which needs broader studies to confirm.

The effectiveness of a synthetic analogue purine nucleoside bases in the treatment of acute respiratory viral infections

Introduction. The aggravation of the comorbid background of patients with ARVI is the main reason for the addition of secondary pathogenic and conditionally pathogenic bacterial flora and, as a result, the development of local and general complications.Аim. To conduct a clinical assessment of the efficacy and safety of the drug Triazavirin based on riamilovir in the treatment of acute respiratory viral infections.Materials and methods. The study conducted on the basis of the medical center of the Federal State Budgetary Educational Institution of the Russian Ministry of Health involved 56 patients with acute recurrent viral infection. Regarding the prescribed therapy, the patients were divided into 2 groups: group 1 (n = 27) from day 2, triazavirin was taken as an antiviral drug (riamilo- vir) 250 mg (1 capsule) 3 times a day for 5 days; group 2 (n = 29) – as an antiviral drug, Kagocel took 2 tablets 3 times a day for 2 days, then 1 tablet 3 times a day for 5 days. The effect of the therapy was assessed by the severity of intoxication syndrome, rhinorrhea, difficulty in nasal breathing, decreased olfactory function, pain syndrome localized in the nasopharynx and throat, cough severity and laboratory results.Results. In patients with 7 days of therapy, the indicator of psychological health increased by 34.7 points in the first group, by 28.8 points in the second group. Vital activity increased by 33.7 points in patients of group 1 and by 23.8 points in the second group. Physical activity tended to increase by 19.5 points and 6.0 points in the first and second groups, respectively.Conclusions. The analysis of changes in the severity of clinical symptoms affecting the quality of life of patients confirmed the effectiveness and safety of the drug Triazavirin.

Novel coenzyme Q6 genetic variant increases susceptibility to pneumococcal disease.

Acute lower respiratory tract infection (ALRI) remains a major worldwide cause of childhood mortality, compelling innovation in prevention and treatment. Children in Papua New Guinea (PNG) experience profound morbidity from ALRI caused by Streptococcus pneumoniae. As a result of evolutionary divergence, the human PNG population exhibits profound genetic variation and diversity. To address unmet health needs of children in PNG, we tested whether genetic variants increased ALRI morbidity. Whole-exome sequencing of a pilot child cohort identified homozygosity for a novel single-nucleotide variant (SNV) in coenzyme Q6 (COQ6) in cases with ALRI. COQ6 encodes a mitochondrial enzyme essential for biosynthesis of ubiquinone, an electron acceptor in the electron transport chain. A significant association of SNV homozygosity with ALRI was replicated in an independent ALRI cohort (P = 0.036). Mice homozygous for homologous mouse variant Coq6 exhibited increased mortality after pneumococcal lung infection, confirming causality. Bone marrow chimeric mice further revealed that expression of variant Coq6 in recipient (that is, nonhematopoietic) tissues conferred increased mortality. Variant Coq6 maintained ubiquinone biosynthesis, while accelerating metabolic remodeling after pneumococcal challenge. Identification of this COQ6 variant provides a genetic basis for increased pneumonia susceptibility in PNG and establishes a previously unrecognized role for the enzyme COQ6 in regulating inflammatory-mediated metabolic remodeling.

Atypical Presentation of Viral Myocarditis with Isolated Fatigue

Viral myocarditis is an inflammatory condition of the myocardium, often caused by viral infections. While the typical presentation includes chest pain, shortness of breath, and palpitations, fatigue as the primary symptom is unusual and presents diagnostic challenges. This report presents the case of a 39-year-old healthy male who complained of isolated fatigue and mild chest discomfort after experiencing flu-like symptoms. Initial workup revealed elevated troponin levels with abnormal ECG findings, raising concerns for myocardial involvement. Coronary angiography ruled out obstructive coronary artery disease, confirming the diagnosis of viral myocarditis. The patient responded well to anti-inflammatory and antithrombotic treatment, and no complications were observed during follow-up. This case highlights the importance of considering viral myocarditis in patients with vague symptoms, especially those with recent viral infections, to prevent delayed diagnosis and potential complications. Early identification and treatment are critical to ensure a favorable outcome.

A retrospective cohort study on the protective effect of influenza vaccination during pregnancy in Gansu Province

ABSTRACT To evaluate the Vaccine Effectiveness (VE) of the Influenza Vaccine (InfV) during pregnancy in Gansu province. A retrospective cohort of pregnant women vaccinated with InfV was constructed using the electronic case system and immunization planning system of Gansu province. Outcome information of Influenza-Like Illness (ILI) in pregnant women after vaccination with InfV during the influenza epidemic seasons from 2019 to 2021 was collected. The log-binomial model was used to estimate the adjusted Risk Ratio (RR), VE, and their Confidence Intervals (CI). The incidence rates of the InfV vaccination group and the non-vaccination group during pregnancy in Gansu province were 4.70% (54/1,150) and 6.91% (16,990/245,754), respectively. The adjusted RR was 0.78 (95%CI 0.43–0.75), and the adjusted VE was 22.20 (95%CI 0.79–40.30). Vaccination with InfV during pregnancy in Gansu province from 2019 to 2021 has a protective effect against ILI in pregnant women, and there is no difference in vaccination at different stages of pregnancy.

Antibiotic treatment recommendations for acute respiratory tract infections in Scandinavian general practices—time for harmonization?

Introduction During recent years, the world—including Scandinavia—has experienced significant challenges with shortages of antibiotics. In Scandinavia, phenoxymethylpenicillin is recommended as first-line antibiotic treatment for most acute respiratory tract infections (ARTIs). However, the Scandinavian countries each constitute rather small markets for phenoxymethylpenicillin. The aim of this discussion paper is to enlighten the differences in Scandinavian ARTI antibiotic treatment recommendations. This information is fundamental for exploring the potential of harmonizing treatment recommendations in Denmark, Norway and Sweden—to help ensure sufficient future supply of phenoxymethylpenicillin. Methods Information from national ARTI antibiotic treatment recommendations from respectively Denmark, Norway and Sweden has been collated. Results Several discrepancies exist in recommendations. Adult dosage varies from a minimum of 660 mg x 4 (Denmark) to a maximum of 2000 mg × 3 (Sweden). Within Norway and Sweden, variations in recommended dosage also exist between the different types of ARTIs. A main challenge is that the tablet strengths recommended, and available on the market in the three countries, differs. Also, antibiotic treatment durations vary significantly between countries and infections treated—from five to 10 days of treatment. Conclusion In the capacity of a well-established network for antibiotic stewardship, we have enlightened the differences in Scandinavian ARTI antibiotic treatment recommendations. This paper is the first step moving forward to scrutinizing the potential for harmonizing recommendations for Denmark, Norway and Sweden—to help ensure continued supply of phenoxymethylpenicillin for use within the Scandinavian countries.

Systematic Review on Influenza Burden in Emerging Markets in 2018–2023—An Evidence Update to Guide Influenza Vaccination Recommendations

Background: Influenza is a contagious respiratory illness responsible for seasonal epidemics and with potential to cause pandemics. The decline in influenza-related studies published since 2018 resulted in data gaps, particularly in emerging markets. Methods: This systematic review searched for studies in six databases and gray literature sources to define the clinical burden of influenza and influenza-like illness (ILIs) and their associated sequelae among humans across emerging markets. Eligible studies were published in English, Spanish, or Chinese between January 2018 and September 2023 and conducted in Asia, the Middle East, Africa, and Latin America. Results: In total, 256 articles were included, mostly on lab-confirmed influenza infections (n = 218). Incidences of lab-confirmed influenza cases in Asia (range 540–1279 cases/100,000 persons) and Sub-Saharan Africa (range 34,100–47,800 cases/100,000 persons) were higher compared to Latin America (range 0.7–112 cases/100,000 persons) and the Middle East and North Africa (range 0.1–10 cases/100,000 persons). Proportions of lab-confirmed influenza cases and influenza-associated outcomes (i.e., hospitalization, ICU admission and death) varied widely across regions. Temporal variation in influenza trend was observed before and during the COVID-19 pandemic. Conclusions: In conclusion, influenza causes significant disease burden in emerging markets. Robust large real-world studies using a similar methodology are needed to have more accurate estimates and compare studies within age groups and regions. Continuous monitoring of influenza epidemiology is important to inform vaccine programs in emerging markets with heavy influenza disease burden.

Peculiarities of children’s health status after acute respiratory viral infections: a look at the problem, ways to solve it

Peculiarities of children’s health status after acute respiratory viral infections: a look at the problem, ways to solve it

Severe Acute Respiratory Infection (SARI) due to Influenza in Post-COVID Resurgence: Disproportionate Impact on Older Māori and Pacific Peoples.

Influenza reemerged after a 2020-2021 hiatus in 2022, but understanding the resurgence needs pre-COVID era surveillance. We compared age- and ethnicity-specific incidence of severe acute respiratory infection (SARI) from a hospital network in Auckland, New Zealand, in 2022 against a baseline, 2012-2019. Annual and monthly influenza SARI incidence per 1000 persons by age and ethnic group between 2012 and 2022 was calculated using resident population as the denominator. The hospitals capture most severe illness of the resident population. Influenza SARI incidence was highest among <1 year olds (2.62; 95% CI: 1.84-3.61) during 2012-2019, lowest at 6-14 years, and did not significantly increase until 50-64 years (0.35; 95% CI: 0.27-0.45), reaching 1.19 (95% CI: 0.57-1.55) in those ≥75 years. In all age groups, incidence was at least threefold higher in Māori and Pacific Peoples. No influenza SARI was identified in 2020-2021. In 2022, despite an early peak, annual incidence (<65 years) was lower than baseline in all ethnic groups, but incidence (≥65 years) in Māori (2.06; 95% CI: 1.22-3.26) and Pacific (3.94; 95% CI: 2.97-5.13) peoples was higher in 2022 than most baseline years, whereas incidence in NMNP (0.22; 95% CI: 0.14-0.32) was lower than any baseline year. After no influenza 2020-2021, Auckland had an early, high, narrow peak in 2022. Stratification by age and ethnicity revealed striking discrepancies in incidence among Māori and Pacific adults over 65 years compared with NMNP adults, with implications for targeted vaccination strategies.

Prediction of ILI following the COVID-19 pandemic in China by using a partial differential equation

Abstract The COVID-19 outbreak has significantly disrupted the lives of individuals worldwide. Following the lifting of COVID-19 interventions, there is a heightened risk of future outbreaks from other circulating respiratory infections, such as influenza-like illness (ILI). Accurate prediction models for ILI cases are crucial in enabling governments to implement necessary measures and persuade individuals to adopt personal precautions against the disease. This paper aims to provide a forecasting model for ILI cases with actual cases. We propose a specific model utilizing the partial differential equation (PDE) that will be developed and validated using real-world data obtained from the Chinese National Influenza Center. Our model combines the effects of transboundary spread among regions in China mainland and human activities’ impact on ILI transmission dynamics. The simulated results demonstrate that our model achieves excellent predictive performance. Additionally, relevant factors influencing the dissemination are further examined in our analysis. Furthermore, we investigate the effectiveness of travel restrictions on ILI cases. Results can be used to utilize to mitigate the spread of disease.

Features of the oropharyngeal microbiota of healthy children and those with acute respiratory infections. A prospective single-center randomized study

Background. The oropharyngeal microbiota is involved in the development of colonization resistance, affecting viral adhesion and metabolism. Any deviations in the stability of the environmental microbial niches of the oropharynx alter the local immune response and can trigger severe chronic somatic disorders. Aim. To compare the composition of the microbiota of children during an episode of respiratory infection and healthy volunteers examined in different periods of convalescence. The obtained data can be used to predict the course of the disease, analyze the risk of complications, and assess the frequency of the diseases in the future. Materials and methods. From 20.01.2022 to 23.12.2022, an open-label prospective single-center randomized comparative study was conducted, which included 120 children aged 5-10 who presented with symptoms of acute respiratory infection. The control group consisted of 15 asymptomatic children examined at different periods of convalescence. The study compared changes in the oral microbiota composition of patients and healthy children. The evaluation was performed using complete 16S rRNA gene sequencing on the Oxford Nanopore platform. Taxonometric analysis at the species and genera level was performed using the Knomics-Biota platform. The R programming language was used for statistical processing. In addition, the parameters of α- and β-diversity of the microbiota were assessed. The Chao1 and Shannon indices were calculated to assess α-diversity (diversity within one community). The Chao1 index is based on the number of species found in the sample and also rare species that are found only 1 or 2 times, thus preventing underestimation of diversity. The Shannon index includes both the number of species and their uniformity in the community. A change in the index indicates the dominance of one or more species. The following indicators were used to assess the β-diversity describing the differences between two microbiota samples at the species and genera level: Bray–Curtis dissimilarity (characterizing the ratios of common and different microorganisms between the samples) and the Aitchison distance (reflecting the differences in the proportions of microorganisms). In addition, the balance between the two groups of microorganisms was evaluated using the NearesBalance method, which characterizes the differences between the microbiota of the main and control groups. Results. The results of our study show that during respiratory infection, the state of the oropharyngeal microbiota is characterized by an increase in α-diversity, which is associated with an increase in the proportion of species of Streptococcus salivarius, Streptococcus pneumoniae, Streptococcus pseudopneumoniae, Streptococcus pyogenes, Streptococcus thermophilus and A12 versus the proportion of Streptococcus mitis, Streptococcus oralis, Streptococcus gwangjuense, Streptococcus sanguinis, Streptococcus gordonii and FDAARGOS_192. In the control group, the oropharyngeal microbiota was divided into two clusters. The dominance of streptococci was observed in the first group (control), while the second group had a more uniform representation. Analysis of the changes in microbial communities in the main and control groups can show the stages of oral microbiota recovery after an acute respiratory infection episode. Conclusion. More research is needed in the field of the oropharyngeal microbiome on a larger sample of healthy children, to standardize the communities of the oropharyngeal microbiota, to study the interaction within communities and with the body as a whole. Analysis of the impact of the microbiota on the frequency and course of respiratory infections and the rate of complications opens up new prospects in treating, rehabilitating, and preventing diseases. These research areas can contribute to improving children's health and quality of life and introducing new approaches into clinical practice.

An Outbreak of Respiratory Viral Infections in a Professional Ice Hockey Team.

Viral acute respiratory infections (ARIs) are an important cause of illness in athletes. However, their impact on ice hockey players is unclear. We describe an outbreak of ARIs in a professional ice hockey team. Contrary to expected influenza, the 40-day outbreak was caused by 8 different respiratory viruses, that is, 2 different influenza A viruses, human coronavirus-NL63 (HCoV-NL63), respiratory syncytial viruses (RSV) A and B, 2 different rhinoviruses, enterovirus D68, and parainfluenza type 2 virus. Only influenza A and HCoV-NL63 were possibly spread within the team thus suggesting an important contraction from the community. The burden of illness was substantial.

Real-World Assessment of Economic and Clinical Outcomes in Thai Patients With Respiratory Syncytial Virus Infection Across Age Groups: A Retrospective Cohort Analysis.

Respiratory syncytial virus (RSV) is an important cause of acute lower respiratory infections worldwide, including Thailand. This study aimed to assess clinical and economic burdens of RSV infections across different age groups in Thailand. A retrospective cohort study was conducted using data from a tertiary care hospital from 2014 to 2021. Patients who tested at least one positive RSV were included and stratified into five age groups (< 2, 2-5, 5-18, 18-65, and > 65 years). Healthcare resource utilization, direct medical costs, and clinical outcomes were analyzed with descriptive statistics. Generalized linear models with gamma distributions and log link were used to model cost outcomes. Costs were reported in 2021 US dollars (USD), with 1 USD = 31.98 Thai Baht. A total of 2122 RSV-positive patients were identified, half of which (1097) were hospitalized. The median (interquartile range [IQR]) total hospitalization costs ranged from USD780 (IQR: USD488-USD1185) in those < 2 years to USD2231 (IQR: USD1250-USD4989) in those aged 65+ years. Case fatality rates among hospitalized patients also varied from 2.5% to 28.4% depending on age. Increased age, presence of comorbidities, and need for critical care were associated with higher hospitalization costs. Among RSV-positive patients, younger children experienced the greatest burden, but poorer outcomes were observed in older adults. Higher costs were associated with older age, comorbidities and critical care needs. Understanding RSV economic burdens is crucial for assessing the cost-effectiveness and public health value of vaccination programs that prioritize at-risk groups to mitigate the public health impact.

Clinical characteristics and in-hospital outcomes associated with RSV-ALRI compared to other viral ALRI in hospitalised children under two years old.

Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory infections (ALRIs) associated hospitalisations in children. It is unclear if hospitalized RSV-ALRI differs in clinically from other viral ALRIs. We aimed to compare the disease impact of hospitalised RSV with other viral ALRI in children under 2 years. We conducted a retrospective study using electronic medical records of children under 2 hospitalized with ALRIs at Sydney Children's Hospitals Network from 2020-2022. We compared demographics and clinical features between RSV-positive and RSV-negative (positive for other viruses) cases. Poisson quasi-likelihood regression was used to estimate adjusted prevalence ratios (aPRs) for three in-hospital outcomes: length of stay, need for respiratory support and intensive care. We examined 330 children under 2 years hospitalized with RSV-positive ALRIs and 330 with RSV-negative ALRIs (positive for other viruses). RSV-positive cases were older (12 vs. 8 months, p<0.001) and more often presented with cough (99% vs. 92%), fever (80% vs. 58%), crackles (89% vs. 76%), hypoxia (50% vs. 36%), and lethargy (36% vs. 20%). They were also more likely to undergo chest x-rays (74% vs. 49%) and receive antibiotics (65% vs. 35%). Adjusted analysis showed RSV-positive children had a higher likelihood of LOS > 2 days (aPR 1.95, 95% CI 1.14-3.36).). However, there were no differences in the need for intensive care or respiratory support. Children with RSV-ALRI exhibited more severe symptoms, received more antibiotics, and had longer hospital stays compared to those with other viral ALRIs, underscoring the need for effective prevention and treatment strategies for RSV.

Enteroviruses, Respiratory Syncytial Virus and Seasonal Coronaviruses in Influenza-like Illness Cases in Nepal

Acute respiratory infection is one of the leading causes of morbidity and mortality among children in low- and middle-income countries. Due to limited diagnostic capability, many respiratory pathogens causing influenza-like illness go undetected. This study aims to detect enterovirus, respiratory syncytial virus, seasonal coronavirus and respiratory pathogens other than influenza in patients with influenza-like illness. A total of 997 (54.3%) respiratory samples (collected in the years 2016–2018) were randomly selected from 1835 influenza-negative samples. The xTAG Respiratory Viral Panel (RVP) FAST v2 panel was used to detect respiratory pathogens including enterovirus/rhinovirus (EV/RV), respiratory syncytial virus (RSV) and seasonal coronavirus (HKU1, OC43, NL63 and 229E). A total of 78.7% (785/997) were positive for respiratory viruses. Of these viruses, EV/RV was detected in 36.3% (362/997), which is the highest number, followed by RSV in 13.7% (137/997). The seasonal coronaviruses HKU1 and OC43 (1.5%, 15/997), NL63 (1.2%, 12/997) and 229E (1%, 10/997) were also detected. The EV/RV-positive samples were sequenced, of which 16.7% (5/30) were confirmed as EVs and were identified as coxsackievirus (CV) types CVB5, CVB3, CV21 and CVB2. The findings of this study highlight the importance of strengthening influenza-like illness surveillance programs in the region by including other respiratory viruses in their scope besides seasonal human influenza viruses.