Respiratory Syncytial Virus Pneumonia Research Articles

Qingfei Formula Protects against Human Respiratory Syncytial Virus-induced Lung Inflammatory Injury by Regulating the MAPK Signaling Pathway.

Qingfei formula (QF) is an empirical formula that shows good clinical efficacy in treating human respiratory syncytial virus pneumonia (RSVP). However, the underlying mechanism remains unclear. This study explores the possible pharmacological actions of QF in RSVP treatment. We used a network pharmacology approach to identify the active ingredients of QF, forecast possible therapeutic targets, and analyze biological processes and pathways. Molecular docking simulation was used to evaluate the binding capability of active ingredients and therapeutic targets. Finally, in vivo experiments confirmed the reliability of network pharmacology-based prediction of underlying mechanisms. The study identified 92 potential therapeutic targets and corresponding 131 active ingredients. Enrichment analysis showed that QF downregulated the MAPK signaling pathway and suppressed the inflammatory injury to the lungs induced by the RSV virus. Molecular docking simulations demonstrated that the core active ingredients of QF could stably bind to genes associated with the MAPK signaling pathway. QF had a protective effect against pneumonia in RSV-infected mice. The QF group exhibited a significant reduction in the levels of inflammatory mediators, interleukin-6 (IL-6), interleukin-8 (CXCL8, IL-8), and P-STAT3, compared to the RSV-induced group. The QF group showed remarkably inhibited MAPK1+3(P-ERK1+2) and MAPK8(P-JNK) protein expression. The current study showed that QF downregulated the MAPK signaling pathway, which inhibited pulmonary inflammation triggered by RSV infection. This study recommends the appropriate use of QF in the clinical management of RSVP.

Application Value of Serum Cytokines in Respiratory Syncytial Virus Pneumonia in Children

Objective: To analyze the relationship between cytokines and clinical manifestations of Respiratory Syncytial Virus (RSV) infection and to investigate the clinical value of cytokines in RSV pneumonia. Methods: Clinical data of RSV positive children admitted to the pediatrics department of Zhengzhou People’s Hospital from November 2021 to June 2023. They were divided into three groups according to different ages, 1-11 months, 12-23 months, 24-36 months, and wheezing group and no wheezing group according to the presence of complications. The clinical data of the children in different groups were compared, and the clinical significance of the children with RSV pneumonia was analyzed by measuring the serum cytokine levels. Results: A total of 64 children were included, 35 from 1-11,16 from 12-23 and 13 in 24-36. There were 35 patients with wheezing and 29 patients with no wheezing. Complications were found in 6 cases and 58 cases were without complications. SPO2 , N and CRP in the 1-November group were lower than those in the 12-2 March group, L was higher than that in the 12-23-month group, the proportion of severe, oxygen inhalation, three concave sign, R, P, IL-8, L were higher than those in the 23-36 month group, Oxygen Saturation (SPO2 ), C-Reactive Proteins (CRP), Procalcitonin (PCT) below the 23-3 June group, the difference is statistically significant; 12-23 month group: CDSS, R, IL-8 were higher than the 24-36 month group. The PCT was lower than that in the 24-3 June group. The difference was statistically significant (P<0.05). Clinical characteristics and cytokine analysis of patients with wheezing group and no wheezing group: the fever days, IL-2, and lymphocyte count were higher in patients without wheezing, with statistically significant differences (P<0.05). In terms of length of stay, R, P, IL-1 β, IL-6, and IL-8, patients with complications were higher than patients without complications, with a statistically significant difference (P<0.05). Conclusion: IL-1β, IL-2, IL-4, IL-6, IL-8 and IL-10 are related with different clinical symptoms and have certain guiding significance for clinical application. IL-1β, IL-2, IL-4, IL-6, IL-8 and IL-10 have different expression levels. IL-2 may be related with wheezing, and IL-1β, IL-6 and IL-8 may be related to complications, which has certain guiding significance for clinical application.

Birth characteristics as predictors of respiratory syncytial virus hospitalisation in newborns to optimise immunisation schedule.

To examine birth characteristics that influence infant respiratory syncytial virus (RSV) hospitalisation risk in order to identify risk factors for severe RSV infections. Retrospective cohort study of 460 771 Sicilian children under 6 months old from January 2007 to December 2017. Hospital discharge records were consulted to identify cases and hospitalisations with International Classification of Diseases, Ninth Revision, Clinical Modification codes 466.11 (RSV bronchiolitis), 480.1 (RSV pneumonia) and 079.6 (RSV). RSV hospitalisation risk was estimated using adjusted odds ratios (aOR) and 95% confidence intervals (95% CI). Overall, 2420 (5.25 per 1000 infants) RSV-related hospitalisations were identified during the study, with girls accounting for 52.8%. RSV hospitalisation risk increased for full-term, transferred, extreme immature, and preterm neonates with serious issues (aOR 3.25, 95% CI 2.90-3.64; aOR 1.86, 95% CI 1.47-2.32; aOR 1.54, 95% CI 1.11-2.07; and aOR 1.48, 95% CI 1.14-1.90). Compared to children born in June, the risk of RSV hospitalisation was significantly higher in children born in January (aOR 28.09, 95% CI 17.68-48.24) and December (aOR 27.36, 95% CI 17.21-46.99). This study identified birth month and diagnosis-related groups as key predictors of RSV hospitalisations. This could help manage monoclonal antibody appropriateness criteria.

COMPARISON OF CLINICAL CHARACTERISTICS OF PATIENTS HOSPITALIZED DUE TO SARS-COV-2, INFLUENZA AND RESPIRATORY SYNCYTIAL VIRUS PNEUMONIA

OBJECTIVE: Influenza, respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection are agents that spread through droplets, have similar symptoms and radiological findings, and can cause respiratory failure. This study was conducted to compare the clinical features and mortality rates of patients with novel coronavirus disease (COVID-19), influenza, and respiratory syncytial virus pneumonia. MATERIAL AND METHODS: A total of 182 patients who were hospitalized at Baskent University Medical Faculty Hospital due to COVID-19, influenza, and RSV were included in the study. Patients were grouped according to their clinical status. Demographic characteristics, comorbidities, laboratory and radiological findings, respiratory support treatments and mortality rates of the patients were recorded and compared between the groups. RESULTS: The mean age was 69.4±7 years in the COVID-19 group (n:115), 72.9±17.1 years in the influenza group (n:33), and 66.5±22.4 years in the RSV group (n:34). There was no difference in age between the groups (p=0.305). The hospitalization rate was higher for male patients in the COVID-19 group (p=0.036). There was no difference between the groups in terms of comorbidities (p>0.05). There was no difference in mortality rates between the COVID-19, RSV, and influenza patient groups (p=0.260). CONCLUSIONS: Viral infections with pulmonary involvement require special attention because they can have a poor clinical course. The severity of the clinical course of COVID-19 pneumonia, which causes deaths in the current century, is not different from the clinical course of viral infections such as influenza and RSV.

Retrospective Analysis of Clinical Patterns and Antibiotic Utilization in Pediatric Patients Hospitalized with Respiratory Syncytial Virus Pneumonia at a Recently Established General Hospital

Retrospective Analysis of Clinical Patterns and Antibiotic Utilization in Pediatric Patients Hospitalized with Respiratory Syncytial Virus Pneumonia at a Recently Established General Hospital

High mortality of patients with severe pneumonia caused by respiratory syncytial virus, August 2021–June 2023, Taiwan

Among the 14 patients with respiratory syncytial virus pneumonia, the majority (n = 8, 57.1 %) were older than 65 years and had health care-associated pneumonia (57.1 %). Over 70 % (n = 10) of them exhibited bacterial co-infection, with a high proportion (64.3 %) requiring mechanical ventilation. The hospital mortality rate was 50 %.

Luteolin-7-O-glucoside promotes macrophage release of IFN-β by maintaining mitochondrial function and corrects the disorder of glucose metabolism during RSV infection

Respiratory syncytial virus (RSV) pneumonia is the main cause of acute bronchiolitis in infants. Luteolin-7-O-glucoside (LUT-7G) is a natural flavonoid, which exists in a variety of plants and has the potential to treat viral pneumonia. We established RSV pneumonia mouse models and RSV-infected cell models. Clodronate liposomes were used to deplete macrophages. We used HE staining and immunohistochemistry to determine inflammatory damage and virus replication. We detected the expression levels of inflammatory factors and IFN-β through qPCR and ELISA. JC-1 kit was used for detecting the cell mitochondrial Membrane potential (MMP). ROS, SOD, and MDA kits were used for detecting intracellular oxidative stress damage. Metabolites of TCA in lung tissue and serum of mice were detected by GC-MS. Pharmacodynamic studies have shown that intervention with LUT-7G can alleviate lung tissue damage caused by RSV infection, inhibit RSV replication, and downregulate TNF-α, IL-1β, and IL-6 mRNA expression. LUT-7G upregulated the IFN-β content and the expression of IFN-β, ISG15, and OAS1 mRNA. In vitro, LUT-7G inhibited RSV-induced cell death, reversed the RSV-induced decrease of MMP and decreased intracellular oxidative stress. Target metabonomics showed that RSV infection upregulated the levels of glycolysis and TCA metabolites in lung tissue and serum, while LUT-7G could improve the disorder of glucose metabolism. The results indicate that LUT-7G can promote the release of IFN-β in the lung, alleviate inflammatory damage, and inhibit RSV replication during RSV infection. These effects may be achieved by protecting the mitochondrial function of alveolar macrophages and correcting the disorder of glucose metabolism.

Hospitalizations due to respiratory syncytial virus (RSV) infections in Germany: a nationwide clinical and direct cost data analysis (2010-2019).

Clinical and direct medical cost data on RSV-related hospitalizations are relevant for public health decision-making. We analyzed nationwide data on RSV-coded hospitalizations from Germany in different age and risk groups. Assessment of RSV-coded hospitalizations (ICD-10-GM RSV-code J12.1/J20.5/J21.0 as primary discharge diagnosis) from 01/2010 to 12/2019, using remote data retrieval from the Hospital Statistics Database of the German Federal Statistical Office. Overall, 205,352 RSV-coded hospitalizations (198,139 children < 18years, 1,313 adults, 5,900 seniors > 59years) were reported (median age < 1year, IQR 0; 1; 56% males, 32% with RSV pneumonia). Annual median RSV-coded hospitalization incidence was 24.8/100,000 persons (IQR 21.3; 27.5); children reported a median incidence of 145.8 (IQR 130.9; 168.3). Between 2010 and 2019, hospitalization incidence increased 1.7-fold/15.1-fold/103-fold in children/adults/seniors. Adults and seniors reported higher rates of underlying chronic conditions, complications, and intensive care treatment than children; of 612 in-hospital fatalities, 103/51/458 occurred in children/adults/seniors. Per-patient mean costs varied between 3286€ ± 4594 in 1-4-year-olds and 7215€ ± 13,564 among adults. Increased costs were associated with immune disorders (2.55-fold increase compared to those without), nervous system disorders (2.66-fold), sepsis (7.27-fold), ARDS (12.85-fold), intensive care (4.60-fold) and ECMO treatment (16.88-fold). The economic burden of RSV-related hospitalizations in Germany is substantial, even when only considering cases with RSV-coded as the primary discharge diagnosis. Children represented the vast majority of RSV-coded hospitalizations. However, adults and seniors hospitalized for RSV were at a higher risk of severe complications, required more costly treatments, and had higher fatality rates; although their RSV-coded hospitalization incidence showed a clear upward trend since 2017, their true hospitalization incidence is still likely to be underestimated due to lack of routine RSV testing in these age groups. Hence, new treatments and vaccines for RSV ideally should also target adults and seniors in addition to children.

Respiratory viral infection and resolution of inflammation: Roles for specialized pro-resolving mediators.

Respiratory viral infections with influenza A virus (IAV) or respiratory syncytial virus (RSV) pose a significant threat to public health due to excess morbidity and mortality. Dysregulated and excessive inflammatory responses are major underlying causes of viral pneumonia severity and morbidity, including aberrant host immune responses and increased risk for secondary bacterial infections. Currently available antiviral therapies have not substantially reduced the risk of severe viral pneumonia for these pathogens. Thus, new therapeutic approaches that can promote resolution of the pathogen-initiated inflammation without impairing host defense would represent a significant advance. Recent research has uncovered the potential for specialized pro-resolving mediators (SPMs) to transduce multipronged actions for the resolution of serious respiratory viral infection without increased risk for subsequent host susceptibility to bacterial infection. Here, we review recent advances in our understanding of SPM production and SPM receptor signaling in respiratory virus infections and the intriguing potential of harnessing SPM pathways to control excess morbidity and mortality from IAV and RSV pneumonia.

Clinical characteristics and risk factors for bronchoscopic airway mucus hypersecretion in childhood pneumonia infected by different pathogens

Objective: To investigate the risk factors for airway mucus hypersecretion in childhood pneumonia infected by different pathogens. Method: A retrospective cohort included 968 children who were hospitalized for Mycoplasma pneumoniae pneumonia (MPP), respiratory syncytial virus (RSV) pneumonia, adenovirus pneumonia and underwent bronchoscopy in Respiratory Department of Children's Hospital of Chongqing Medical University from January 2019 to December 2021 was conducted. The children were divided into two groups distinguished by airway mucus secretion according to the airway mucus hypersecretion score which were scored according to the mucus secretion under the bronchoscope. The demographic characteristics, clinical characteristics, laboratory tests and disease severity of the two groups were compared. And the risk factors for the development of airway mucus hypersecretion in two groups were analyzed. Chi square test, Mann-Whithey U test and Fisher exact test were used to analyze the differences between the two groups, and multivariate Logistic regression was used to analyze the influencing factors. Result: There were 559 males and 409 females in the 968 children, with an age of 4.0 (1.4, 6.0) years. Among the 642 children with MPP, 185 cases were in the hypersecretion group and 457 cases were in the non-hypersecretion group. There were 41 cases in the hypersecretion group and 160 cases in the non-hypersecretion group of 201 children with RSV pneumonia. In the 125 children with adenovirus pneumonia, there were 39 cases in the hypersecretion group and 86 cases in the non-hypersecretion group. In these children, the age of children in the hypersecretion group was older than that in the non-hypersecretion group (6.0 (4.0, 7.0) vs. 5.0 (3.0, 7.0) years old, 1.5 (0.5, 3.6) vs. 0.8 (0.4, 1.6) years old, 2.0 (1.2, 4.5) vs. 1.3 (0.8, 2.0) years old, U=35 295.00, 2 492.00, 1 101.00, all P<0.05). Through multivariate Logistic regression analysis it found that increased risk of airway mucus hypersecretion was present in childhood MPP with increase in peripheral blood white blood cell count (OR=3.30, 95%CI 1.51-7.93, P=0.004) or increase in neutrophil ratio (OR=2.24, 95%CI 1.16-4.33, P=0.016) or decrease in lymphocyte count (OR=3.22, 95%CI 1.66-6.31, P<0.001) or decrease in serum albumin (OR=2.00, 95%CI 1.01-3.98, P=0.047). The risk of airway mucus hypersecretion was increased in children with RSV pneumonia combined with elevated peripheral blood eosinophils (OR=3.04, 95%CI 1.02-8.93, P=0.043). Meanwhile, airway mucus hypersecretion was associated with severe pneumonia (OR=2.46, 95%CI 1.03-6.15, P=0.047) in children with RSV pneumonia. Older age was associated with increased risk of airway mucus hypersecretion in children with adenovirus pneumonia (OR=1.02, 95%CI 1.00-1.04, P=0.026). In these children with occurrence of pulmonary rales, wheezes or sputum sounds (OR=3.65, 95%CI 1.22-12.64, P=0.028) had an increased risk of airway mucus hypersecretion. Neutrophils in bronchoalveolar lavage fluid (BALF) demonstrated higher ratio in hypersecretion group from children with MPP (0.65 (0.43, 0.81) vs. 0.59 (0.34, 0.76), U=24 507.00, P<0.01), while the proportion of macrophages in BALF was lower (0.10 (0.05, 0.20) vs. 0.12 (0.06, 0.24), U=33 043.00, P<0.05). Nucleated cell count and neutrophil ratio in BALF were higher in hypersecretion group of children with RSV pneumonia (1 210 (442, 2 100)×106 vs. 490 (210, 1 510)×106/L, 0.43 (0.26, 0.62) vs. 0.30 (0.13, 0.52), U=2 043.00, 2 064.00, all P<0.05). Conclusions: The increase in peripheral blood white blood cell count, neutrophil ratio and decrease in lymphocyte count, serum albumin in children with MPP is related to the development of airway mucus hypersecretion. In children with RSV pneumonia, the abnormal increase of eosinophils in peripheral blood has relationship with hypersecretion. The appearance of lung rale, wheezing, and sputum rale are associated with airway mucus hypersecretion in children with adenovirus pneumonia. In addition, local neutrophil infiltration in the respiratory tract is closely related to the occurrence of airway mucus hypersecretion caused by Mycoplasma pneumoniae and RSV infection.

Multi-omics analysis reveals underlying host responses in pediatric respiratory syncytial virus pneumonia.

Respiratory syncytial virus (RSV) is an important pathogen causing pneumonia in children. Few studies have used multi-omics data to investigate the pathogenies of RSV pneumonia. Here, metabolomics was first used to identify potential biomarkers for RSV diagnosis. In the training cohort, serum from 36 healthy controls (HCs), 45 RSV pneumonia children, and 32 infectious disease controls (IDCs) were recruited. After analyses, six metabolites had potential diagnostic value. Using an independent cohort of 49 subjects, two biomarkers (neuromedin Nand histidyl-proline diketopiperazine) were validated. Next, multi-omics analysis were applied to analyze the pathogenies of RSV pneumonia. Accumulation of collagen in the serum of RSVs indicated that RSV infection could lead to increased levels of soluble collage. Activation of the complement system and imbalance in lipid metabolism were also observed in RSV patients. The multi-omics analysis presented here revealed the signature protein and metabolite changes in serum caused by RSV infection.

Epidemiology and Characteristics of Respiratory Syncytial Virus Pneumonia in Critically Ill Adults.

Severe respiratory syncytial virus (RSV)-associated pneumonia in adults has rarely been addressed. We investigated the burden and clinical characteristics of severe RSV-associated pneumonia in critically ill adult patients. We analyzed a prospective cohort of 2865 adults with severe pneumonia who were admitted to the intensive care unit in a 2700-bed tertiary care hospital from 2010 to 2019. The epidemiology, characteristics, and outcomes of 92 cases of severe RSV-associated pneumonia and 163 cases of severe influenza virus (IFV)-associated pneumonia were compared. Of 1589 cases of severe community-acquired pneumonia, the incidence of RSV-associated pneumonia was less than half that of IFV-associated pneumonia (3.4% vs 8.1%). However, among 1276 cases of severe hospital-acquired pneumonia (HAP), there were slightly more cases of RSV-associated than IFV-associated pneumonia (3.8% vs 3.5%). During the 9 epidemic seasons, RSV-A (5 seasons) and RSV-B (4 seasons) predominated alternately. Structural lung disease, diabetes mellitus, and malignancy were common underlying diseases in both groups. Immunocompromise (57.6% vs 34.4%; P < .001) and hospital acquisition (47.8% vs 23.9%; P < .001) were significantly more common in the RSV group. Coinfection with Streptococcus pneumoniae (3.3% vs 9.8%; P = .08) and methicillin-susceptible Staphylococcus aureus (1.1% vs 6.8%; P = .06) tended to be less frequent in the RSV group. The 90-day mortality was high in both groups (39.1% vs 40.5%; P = .89). RSV infection was associated with substantial morbidity and mortality in critically ill adult patients, similar to IFV. The relatively higher incidence of RSV in severe HAP suggests that the transmissibility of RSV can exceed that of IFV in a hospital setting.

Study Limitations and Harmonious Discord of Results Reveal Melody to Public Health Measures.

Study Limitations and Harmonious Discord of Results Reveal Melody to Public Health Measures.

Burden of Respiratory Syncytial Virus Related Acute Lower Respiratory Tract Infection in Hospitalized Thai Children: A 6-Year National Data Analysis.

This study sought to determine the epidemiology, seasonal variations, morbidity, and mortality of respiratory syncytial virus (RSV) infection among hospitalized children with lower respiratory tract infection in Thailand. In addition, we assessed the risk factors associated with severe RSV lower respiratory tract infection (LRTI)-related morbidity and mortality. The data were reviewed retrospectively from the National Health Security Office for hospitalized children younger than 18 years old diagnosed with RSV-related LRTI in Thailand, between the fiscal years of 2015 to 2020. The RSV-related LRTIs were identified using the International Statistical Classification of Diseases and Related Health Problems, 10th Revision, Thai Modification. ICD-10-TM codes J12.1, J20.5, and J21.0, which represent respiratory syncytial virus pneumonia, acute bronchitis due to respiratory syncytial virus, and acute bronchiolitis due to respiratory syncytial virus, respectively, were studied. During the study period, RSV-related LRTI accounted for 19,340 of the 1,610,160 hospital admissions due to LRTI. RSV pneumonia was the leading cause of hospitalization (13,684/19,340; 70.76%), followed by bronchiolitis (2849/19,340; 14.73%) and bronchitis (2807/19,340; 14.51%), respectively. The highest peak incidence of 73.55 percent occurred during Thailand's rainy season, from August to October. The mortality rate of RSV-related LRTI in infants younger than 1 year of age was 1.75 per 100,000 person years, which was significantly higher than that of children 1 to younger than 5 years old and children 5 to younger than 18 years old (0.21 per 100,000 person years and 0.01 per 100,000 person years, respectively, p-value &lt; 0.001). Factors associated with mortality were congenital heart disease, hematologic malignancy, malnutrition, and neurological disease. In children with RSV LRTI, pneumonia was the leading cause of hospitalization. The admission rate was highest during the rainy season. Mortality from RSV-related LRTI was higher in children under 1 year old and in children with underlying illnesses; future preventive interventions should target these groups of patients.

2192. Clinical and Molecular Characteristics of Severe Respiratory Syncytial Virus Pneumonia in Critically Ill Adults

Abstract Background Respiratory syncytial virus (RSV) has been increasingly recognized as a frustrating cause of morbidity and mortality in adults. However, the clinical impact and molecular characteristics of severe RSV-associated pneumonia in critically ill adult patients have rarely been addressed. Methods This study, nested in a prospective cohort of severe pneumonia, was conducted at a 2,700-bed tertiary care hospital and comprised two parts. In part 1, the clinical characteristics of severe RSV-associated pneumonia were compared with severe influenza virus (IFV)-associated pneumonia between 2010 and 2019. In part 2, we performed phylogenetic and amino acid analyses of the G protein of RSV strains from three groups of different infection severity between 2015 and 2019 (Figure 1). Figure 1.Clinical samples for whole-genome sequencing in part 2. Results In part 1, 92 RSV- and 163 IFV-positive patients were identified. Structural lung diseases, diabetes mellitus, and malignancy were common underlying diseases in both groups. Immunocompromise (57.6% vs. 34.4%, p &amp;lt; 0.001) and hospital acquisition (47.8% vs. 23.9%, p &amp;lt; 0.001) were significantly more common in the RSV group. Clinical manifestations at diagnosis between the groups were generally similar. The mortalities of patients in both groups were similarly high (Table 1). In part 2, 26 RSV strains from three groups (group 1: 11 strains, group 2: 8 strains, and group 3: 7 strains) were analyzed. All isolated RSV-A and -B strains belonged to the ON1 and the BA9 genotypes, respectively. The phylogenetic analysis revealed that the adult severe pneumonia strains clustered by contemporary strains rather than other severe pneumonia strains. There were no significantly different genetic variations among the three groups, including the subtype clades, amino acid sequence substitutions, and changes in potential glycosylation sites. Table 1.Characteristic and outcomes of 255 patients with virus-associated severe pneumonia Conclusion Severe RSV pneumonia was more commonly associated with hospital acquisition and immunocompromised status. Overall clinical features and mortalities of the RSV group were comparable to the IFV group. The molecular characteristics of RSV strains from the adults with severe pneumonia were not distinct from strains from non-pneumonic adults or children, underscoring that the severity of RSV respiratory tract infection is mainly determined by host factors, not by viral factors. Disclosures All Authors: No reported disclosures.

Characteristics of Respiratory Syncytial Virus versus Influenza Infection in Hospitalized Patients of Peru: A Retrospective Observational Study.

Respiratory syncytial virus (RSV) and influenza infections are important causes of respiratory illness associated with hospitalizations in children in Peru; however, comparisons of RSV and influenza hospitalization across all age groups are not available in Peru. Therefore, we conducted an observational, retrospective study between May 2015 and October 2021 using hospitalization from RSV and influenza infection data obtained from SUSALUD (open data) in Peru to compare the baseline characteristics of sex, age, region, and infection type. For the study, 2696 RSV-infected and 1563 influenza-infected hospitalized patients from different age groups were included. Most hospitalizations from RSV infection and the influenza virus occurred in children <5 years of age (86.1% vs. 32.2%, respectively). Compared with influenza infection, RSV infection was less likely to occur in individuals ≥5 years of age (adjusted odds ratio (aOR) = 0.07; 95% confidence interval (CI), 0.06–0.08; p < 0.0001; compared to <5 years of age), and more likely to occur in highlands (aOR = 1.75; 95% CI, 1.46–2.07; p < 0.0001, compared to coast region), and jungle region (aOR = 1.75; 95% CI, 1.27–2.41; p = 0.001, compared to coast region). Among the respiratory complications, RSV pneumonia was less likely to occur between different age groups (aOR = 0.29; 95% CI, 0.22–0.37; p < 0.0001, compared to <5 years of age), compared with influenza pneumonia. These findings on the RSV-hospitalization and its complications are helpful for health services planning and may increase awareness of the Peruvian population’s RSV and influenza disease burden.

Age-specific hospitalization risk of primary and secondary respiratory syncytial virus infection among young children

ObjectivesElucidating the infection dynamics that lead to severe respiratory syncytial virus (RSV) pneumonia and hospitalization among young children are critical. We explored the role of infection parity as well as age in months for RSV-associated hospitalization among young children in Japan. MethodsWe used a sequential transmission catalytic model to capture the transmission mechanisms of RSV among infants in an endemic state. We investigated data on the age-dependent seroprevalence and incidence rate of hospitalization in Japan, and jointly estimated the age-specific risk of hospitalization during primary RSV infection and relative risk of hospitalization during secondary infection in children aged <5 years. ResultsThe estimated risk of hospitalization with primary infection was 0.08 (95% CI: 0.05-0.14) in infants aged 0-2 months. The estimated relative risk of hospitalization owing to secondary infection was 0.18 (95% CI: 0.01-2.04). ConclusionOur simple models successfully captured the infection dynamics of RSV among young children in Japan. The age group of early infancy may be most vulnerable to infection and hospitalization, offering key insights into future vaccinations. The burden of hospitalization from secondary infection may be less important in young children.

P9.29: Respiratory syncytial virus Pneumonia in a LDLT Recipient Transplanted for COVID 19 Precipitated ACLF: Managed With Ribavirin and IvIg

P9.29: Respiratory syncytial virus Pneumonia in a LDLT Recipient Transplanted for COVID 19 Precipitated ACLF: Managed With Ribavirin and IvIg

Respiratory syncytial virus pneumonia in an immunocompetent adult: an important differential diagnosis of COVID-19.

We present a case of RSV pneumonia in a 36-year-old immunocompetent young female patient having a contacted history of RSV pneumonia from her daughter. Since the clinical and radiological findings were similar, clinicians should consider this classical disease in differential diagnosis, particularly in the pandemic settings of COVID-19.

Respiratory syncytial virus pneumonia in a LDLT recipient transplanted for COVID 19 precipitated ACLF: Treated with ribavirin and IVIg

Respiratory syncytial virus pneumonia in a LDLT recipient transplanted for COVID 19 precipitated ACLF: Treated with ribavirin and IVIg