Respiratory Virus Disease Research Articles

Establishment of a Quadruplex RT-qPCR for the Detection of Canine Coronavirus, Canine Respiratory Coronavirus, Canine Adenovirus Type 2, and Canine Norovirus

Canine coronavirus (CCoV), canine respiratory coronavirus (CRCoV), canine adenovirus type 2 (CAV-2), and canine norovirus (CNV) are important pathogens for canine viral gastrointestinal and respiratory diseases. Especially, co-infections with these viruses exacerbate the damages of diseases. In this study, four pairs of primers and probes were designed to specifically amplify the conserved regions of the CCoV M gene, CRCoV N gene, CAV-2 hexon gene, and CNV RdRp gene. After optimizing different reaction conditions, a quadruplex RT-qPCR was established for the detection of CCoV, CRCoV, CAV-2, and CNV. The specificity, sensitivity, and repeatability of the established assay were evaluated. Then, the assay was used to test 1688 clinical samples from pet hospitals in Guangxi province of China during 2022–2024 to validate its clinical applicability. In addition, these samples were also assessed using the reported reference RT-qPCR assays, and the agreements between the developed and reference assays were determined. The results indicated that the quadruplex RT-qPCR could specifically test only CCoV, CRCoV, CAV-2, and CNV, without cross-reaction with other canine viruses. The assay had high sensitivity with limits of detection (LODs) of 1.0 × 102 copies/reaction for CCoV, CRCoV, CAV-2, and CNV. The repeatability was excellent, with intra-assay variability of 0.19–1.31% and inter-assay variability of 0.10–0.88%. The positivity rates of CCoV, CRCoV, CAV-2, and CNV using the developed assay were 8.59% (145/1688), 8.65% (146/1688), 2.84% (48/1688), and 1.30% (22/1688), respectively, while the positivity rates using the reference assays were 8.47% (143/1688), 8.53% (144/1688), 2.78% (47/1688), and 1.24% (21/1688), respectively, with agreements of more than 99.53% between two methods. In conclusion, a quadruplex RT-qPCR with high sensitivity, specificity, and repeatability was developed for rapid, and accurate detection of CCoV, CRCoV, CAV-2, and CNV.

Impact of Viral Lower Respiratory Tract Infection (LRTI) in Early Childhood (0-2 Years) on Lung Growth and Development and Lifelong Trajectories of Pulmonary Health: A National Institutes of Health (NIH) Workshop Summary.

Viral lower respiratory tract infections (LRTI) are ubiquitous in early life. They are disproportionately severe in infants and toddlers (0-2 years), leading to more than 100,000 hospitalizations in the United States per year. The recent relative resilience to severe Coronavirus disease (COVID-19) observed in young children is surprising. These observations, taken together, underscore current knowledge gaps in the pathogenesis of viral lower respiratory tract diseases in young children and respiratory developmental immunology. Further, early-life respiratory viral infections could have a lasting impact on lung development with potential life-long pulmonary sequelae. Modern molecular methods, including high-resolution spatial and single-cell technologies, in concert with longitudinal observational studies beginning in the prenatal period and continuing into early childhood, promise to elucidate developmental pulmonary and immunophenotypes following early-life viral infections and their impact on trajectories of future respiratory health. In November 2019, under the auspices of a multi-disciplinary Workshop convened by the National Heart Lung Blood Institute and the Eunice Kennedy Shriver National Institute of Child Health and Human Development, experts came together to highlight the challenges of respiratory viral infections, particularly in early childhood, and emphasize the knowledge gaps in immune, virological, developmental, and clinical factors that contribute to disease severity and long-term pulmonary morbidity from viral LRTI in children. We hope that the scientific community will view these challenges in clinical care on pulmonary health trajectories and disease burden not as a window of susceptibility but as a window of opportunity.

Plant resources for immunonutrients and immunomodulators to combat infectious respiratory viral diseases: a review.

Boosting the immune system has become a crucial aspect in the global battle against the COVID-19 pandemic and other similar infections to protect oneself against symptoms, especially in the prevention of viral infections of the lower respiratory tract. The importance of conducting more studies to create successful herbal formulations as infection prevention measures is emphasized in this review, which looks at the function of immune-boosting nutrients, medicinal plants, and herbal treatments. We reviewed and analyzed 207 studies published from 1946 to the present using reputable databases like Google Scholar, PubMed, and NCBI. The review examined 115 plant species in total and identified 12 key nutrients, including vitamins A, D, C, omega-3 fatty acids, iron, and zinc, while noting that four plant families, Rosaceae, Asteraceae, Amaryllidaceae, and Acanthaceae, show potential against respiratory infections like influenza, RSV, and SARS-CoV. To lower the risk of infection, it is recommended to consume nutritious meals that have immune-modulating qualities. Information on the bioactive components of medicinal herbs, spices, and plants that have been effective in treating respiratory viral infections and related conditions is compiled in this review, which highlights phytoactive substances with antibacterial and antiviral activity as effective modulators to lower the risk of infections. Furthermore, it is highlighted that ancient knowledge systems, like Ayurveda and Naturopathy, should be integrated to help develop new herbal formulations. To improve immunity and lessen vulnerability to serious respiratory infections, the results highlight the need for including immune-modulating foods and plant-based medicines into everyday routines.

Clinical profile, risk factors, disease severity, and outcome for COVID-19 disease in patients with tuberculosis on treatment under the National Tuberculosis Elimination Program: a cohort of 1400 patients.

COVID-19 affected millions of people worldwide, and tuberculosis (TB) continues to affect millions of people each year. The combined pandemic of COVID-19 and TB had a catastrophic effect on healthcare policies and healthcare setups around the globe. The clinical profile and factors affecting the outcome of COVID-19 disease in TB patients on treatment in field conditions have not been studied in detail. The present study attempted to study the occurrence of COVID-19 among patients on TB treatment in terms of severity of COVID-19 disease and outcome of both COVID-19 and TB in patients at National Tuberculosis Elimination Program treatment centers over a period of one year during peak COVID-19 times. Out of 1400 TB patients enrolled, 65 (5%) suffered from COVID-19 disease. Of the 65 TB patients with COVID-19 disease, 37 (57%) were male and under 45 years old, 33 (51%) had a TB diagnosis after first receiving a COVID-19 diagnosis, 29 (45%) had a TB diagnosis first, and received anti-TB treatment before receiving a COVID-19 diagnosis, and only 3 patients (5%) had a COVID-19 and TB diagnosis concurrently. The majority of 59 (91%) patients had mild COVID-19 disease. The outcome of TB treatment was available in 25 patients out of these 65 COVID-19-positive patients, with 21 (84%) patients having a favorable outcome. Out of the 65 COVID-19-positive patients, 4/25 (16%) had unfavorable outcomes, with one patient (4%) failing TB treatment and two patients (8%) dying. This is the first study from India that studied the occurrence and course of COVID-19 among a large number of TB patients taking anti-TB treatment under programmatic conditions. Due to the similarity in symptoms of TB and certain viral respiratory illnesses, a protocol should be established for health care to check patients for both illnesses.

Asthma development is associated with low mucosal IL-10 during viral infections in early life.

Viral infection is a common trigger of severe respiratory illnesses in early life and a risk factor for later asthma development. The mechanism leading to asthma could involve an aberrant airway immune response to viral infections, but this has rarely been studied in a human setting. To investigate insitu virus-specific differences in upper airway immune mediator levels during viral episodes of respiratory illnesses and the association with later asthma. We included 493 episodes of acute respiratory illnesses in 277 children aged 0-3 years from the COPSAC2010 mother-child cohort. Levels of 18 different immune mediators were assessed in nasal epithelial lining fluid using high-sensitivity MesoScale Discovery kits and compared between children with and without viral PCR-identification in nasopharyngeal samples. Finally, we investigated whether the virus-specific immune response was associated with asthma by age 6 years. Viral detection were associated with upregulation of several Type 1 and regulatory immune mediators, including IFN-ɣ, TNF-α, CCL4, CXCL10 and IL-10 and downregulation of Type 2 and Type 17 immune mediators, including CCL13, and CXCL8 (FDR <0.05). Children developing asthma had decreased levels of IL-10 (FDR <0.05) during viral episodes compared to children not developing asthma. We described the airway immune mediator profile during viral respiratory illnesses in early life and showed that children developing asthma by age 6 years have a reduced regulatory (IL-10) immune mediator level. This provides insight into the interplay between early-life viral infections, airway immunity and asthma development.

Influenza and COVID-19 Vaccination Coverage Among Health Care Personnel - National Healthcare Safety Network, United States, 2023-24 Respiratory Virus Season.

The Advisory Committee on Immunization Practices (ACIP) recommends that health care personnel receive an annual influenza vaccine. In September 2023, ACIP recommended that everyone aged ≥6 months receive a 2023-2024 COVID-19 vaccine. Health care facilities, including acute care hospitals and nursing homes, report vaccination of health care personnel against influenza and COVID-19 to CDC's National Healthcare Safety Network (NHSN). During October 2023-March 2024, NHSN defined up-to-date COVID-19 vaccination as receipt of a 2023-2024 COVID-19 vaccine. This analysis describes influenza and 2023-2024 COVID-19 vaccination coverage among health care personnel working in acute care hospitals and nursing homes during the 2023-24 respiratory virus season (October 1, 2023-March 31, 2024). Influenza vaccination coverage was 80.7% among health care personnel at acute care hospitals and 45.4% among health care personnel at nursing homes. Coverage of 2023-2024 COVID-19 vaccination was 15.3% among health care personnel at acute care hospitals and 10.5% among health care personnel at nursing homes. Respiratory viral diseases including influenza and COVID-19 pose risks to health care personnel in U.S. health care settings, and vaccination of health care personnel is an effective strategy for maintaining a healthy workforce and improving health care system resiliency.

Impact of universal masking in reducing the risk of nosocomial respiratory viruses among people with cancer.

Universal masking within healthcare settings was adopted to combat the spread of coronavirus disease 2019 (COVID-19). In addition to mitigating the risk for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, it also had an added benefit of preventing the nosocomial transmission of other respiratory viral diseases. This study examines the impact of the masking intervention on nosocomial respiratory viral infections (RVI) in vulnerable sub-populations of people with cancer at a tertiary care hospital. Interrupted time series analysis. We reviewed non-SARS-CoV-2 nosocomial RVI between January 1, 2017 and December 31, 2023 and compared its quarterly trends before (January 2017 to March 2020) and after (April 2020 to December 2023) the universal masking intervention was implemented. Prior to the masking policy, there was no significant change in the quarterly rate of non-SARS-CoV-2 nosocomial RVI (baseline trend: P = 0.662). Crude infection rates decreased from 5.6% preintervention to 4.3% after the masking policy was implemented (P < 0.001). Quarterly trends continued to steadily decline post-intervention (β = -0.10, SE = 0.04, P < 0.007). Our results suggest that universal face masking is associated with reduced non-SARS-CoV-2 nosocomial RVI, providing further evidence to support the continued use of face masks in healthcare settings to protect the health of immunocompromised patients.

In Silico evaluation of the anti-influenza potential of Streptomyces bioactive compounds

Influenza, a highly contagious respiratory viral disease characterized by its short incubation period and severe symptoms, is treatable with antiviral drugs targeting viremia. Among new antiviral agents, Actinobacteria, particularly from the Streptomyces genus, are notable for their ability to produce potent antiviral compounds. This study evaluates the antiviral potential of Streptomyces sp. KSF 103, isolated from Kuala Sat, Jerantut, Pahang, against the Influenza A virus (IAV). Using molecular docking tools such as AutoDock Vina and PyMOL, the interactions of four compounds – hypoxanthine, vitamin D, purine, and aminocaproic acid – were analyzed against IAV proteins. Vitamin D exhibited the highest binding affinity against H3N2’s M2 (−9.6 kcal/mol) and HA (−9.2 kcal/mol) proteins. Additionally, RMSD dynamics parameters indicated that the best-scoring complexes are predicted to be satisfactorily stable under physiological settings. These findings suggest that Streptomyces sp. KSF 103 could be a promising source for developing new antiviral treatments against influenza.

Study on the index system for field epidemiological investigations of viral respiratory infectious diseases

The study used the Delphi method to conduct two rounds of expert consultations involving 23 experts nationwide, aiming to establish the comprehensive index system for field epidemiological investigations of viral respiratory infectious diseases and determine the weights assigned to each index through the hierarchical analysis. Both rounds of consultation witnessed a 100% participation rate among all experts, with a coefficient of authority (Cr) reaching 0.89. The Kendall's W coefficients for assessing the importance and feasibility in both rounds were 0.108, 0.234, 0.439 and 0.427, respectively. Finally, an index system consisting of seven first-level indicators, 18 second-level indicators, and 36 third-level indicators was constructed for the technical guidelines governing field epidemiological investigations into viral respiratory infectious diseases, and the weight of each indicator was established. The index system constructed in this study has a high degree of scientificity, reliability and operability, but it still needs to be further adjusted and improved in combination with the epidemiological characteristics of viral respiratory infectious diseases.

Design of an Epitope-Based Vaccine Against MERS-CoV.

Background and Objectives: Middle East Respiratory Syndrome (MERS) is a viral respiratory illness caused by a coronavirus called Middle East respiratory syndrome. In the current study, immunoinformatics studies were applied to design an epitope-based vaccine construct against Middle East Respiratory Syndrome. Materials and Methods: In this study, epitopes base vaccine construct was designed against MERS using immunoinformatics approach. Results: In this approach, the targeted proteins were screened, and probable antigenic, non-allergenic, and good water-soluble epitopes were selected for vaccine construction. In vaccine construction, the selected epitopes were joined by GPGPG linkers, and a linear multi-epitope vaccine was constructed. The vaccine construct underwent a physiochemical property analysis. The 3D structure of the vaccine construct was predicted and subjected to refinement. After the refinement, the 3D model was subjected to a molecular docking analysis, TLRs (TLR-3 and TLR-9) were selected as receptors for vaccine construct, and the molecular docking analysis study determined that the vaccine construct has binding ability with the targeted receptor. Conclusions: The docking analysis also unveils that the vaccine construct can properly activate immune system against the target virus however experimental validation is needed to confirm the in silico findings further.

Monitoring of Respiratory Disease Patterns in a Multimicrobially Infected Pig Population Using Artificial Intelligence and Aggregate Samples

A 24/7 AI sound-based coughing monitoring system was applied in combination with oral fluids (OFs) and bioaerosol (AS)-based screening for respiratory pathogens in a conventional pig nursery. The objective was to assess the additional value of the AI to identify disease patterns in association with molecular diagnostics to gain information on the etiology of respiratory distress in a multimicrobially infected pig population. Respiratory distress was measured 24/7 by the AI and compared to human observations. Screening for swine influenza A virus (swIAV), porcine reproductive and respiratory disease virus (PRRSV), Mycoplasma (M.) hyopneumoniae, Actinobacillus (A.) pleuropneumoniae, and porcine circovirus 2 (PCV2) was conducted using qPCR. Except for M. hyopneumoniae, all of the investigated pathogens were detected within the study period. High swIAV-RNA loads in OFs and AS were significantly associated with a decrease in respiratory health, expressed by a respiratory health score calculated by the AI The odds of detecting PRRSV or A. pleuropneumoniae were significantly higher for OFs compared to AS. qPCR examinations of OFs revealed significantly lower Ct-values for swIAV and A. pleuropneumoniae compared to AS. In addition to acting as an early warning system, AI gained respiratory health data combined with laboratory diagnostics, can indicate the etiology of respiratory distress.

Pediatric Respiratory Hospitalizations in the Pre-COVID-19 Era: The Contribution of Viral Pathogens and Comorbidities to Clinical Outcomes, Valencia, Spain.

Viral respiratory diseases place a heavy burden on the healthcare system, with children making up a significant portion of related hospitalizations. While comorbidities increase the risk of complications and poor outcomes, many hospitalized children lack clear risk factors. As new vaccines for respiratory viral diseases emerge, this study examined pediatric respiratory hospitalizations, focusing on viral etiology, complication rates, and the impact of comorbidities to guide future policy. Data were analyzed from eight pre-COVID influenza seasons (2011/2012-2018/2019) involving patients under 18 years hospitalized with respiratory complaints across 4-10 hospitals in Valencia, Spain. Respiratory specimens were tested for eight viral targets using multiplex real-time reverse-transcription polymerase chain reaction. Demographics, clinical outcomes, discharge diagnoses, and laboratory results were examined. Among the hospitalized children, 26% had at least one comorbidity. These children had higher rates of pneumonia, asthma exacerbation, and pneumothorax, and were twice as likely to require ICU admission, though mechanical ventilation and length of stay were similar to those without comorbidities. Respiratory syncytial virus (RSV) was the most common virus detected (23.1%), followed by rhinovirus/enterovirus (9.5%) and influenza (7.2%). Viral codetection decreased with age, occurring in 4.6% of cases. Comorbidities increase the risk of complications in pediatric respiratory illnesses, however, healthcare utilization is driven largely by otherwise healthy children. Pediatric viral vaccines could reduce this burden and should be further evaluated.

Ciliary Function, Antigen Stasis and Asthma.

The prevalence of asthma exceeds 3% of the population. Asthma is observed to be more common in children following severe viral lower respiratory illnesses that affect ciliary function, but mechanisms linking ciliary function to asthma pathogenesis have been obscure. Recent data regarding primary ciliary dyskinesia (PCD) may help us to understand the association. Here, I will review what is known about the relationship between ciliary function and asthma. PCD is caused by pathologic variants in over 50 different genes that affect the structure and function of motile cilia. At the cellular level, a characteristic feature shared by most PCD patients is that antigens and other particles are not cleared from the epithelial surface. Poor antigen clearance results in pro-oxidant pathway activation and airway epithelial damage and may predispose PCD patients to DUOX1- and IL33-mediated asthma. Secondary ciliary dysfunction, such as that caused by viruses or by smoking, can also contribute to asthma development. Moreover, variants in genes that affect the function of cilia can be associated with poor lung function, even in the absence of PCD, and with increased asthma severity. The role of antigen stasis on the surface of dysfunctional airway cilia in the pathophysiology of asthma is a novel area for research, because specific airway clearance techniques and other therapeutic interventions, such as antioxidants, could be of value in preventing the development of asthma.

Antibiotic use during influenza infection augments lung eosinophils that impair immunity against secondary bacterial pneumonia.

A leading cause of mortality after influenza infection is the development of a secondary bacterial pneumonia. In the absence of a bacterial superinfection, prescribing antibacterial therapies is not indicated but has become a common clinical practice for those presenting with a respiratory viral illness. In a murine model, we found that antibiotic use during influenza infection impaired the lung innate immunologic defenses toward a secondary challenge with methicillin-resistant Staphylococcus aureus (MRSA). Antibiotics augment lung eosinophils, which have inhibitory effects on macrophage function through the release of major basic protein. Moreover, we demonstrated that antibiotic treatment during influenza infection caused a fungal dysbiosis that drove lung eosinophilia and impaired MRSA clearance. Finally, we evaluated 3 cohorts of hospitalized patients and found that eosinophils positively correlated with antibiotic use, systemic inflammation, and worsened outcomes. Altogether, our work demonstrates a detrimental effect of antibiotic treatment during influenza infection that has harmful immunologic consequences via recruitment of eosinophils to the lungs, thereby increasing the risk of developing a secondary bacterial infection.

Shedding light on the cellular mechanisms involved in the combined adverse effects of fine particulate matter and SARS-CoV-2 on human lung cells

Airborne pathogens represent a topic of scientific relevance, especially considering the recent COVID-19 pandemic. Air pollution, and particulate matter (PM) in particular, has been proposed as a possible risk factor for the onset and spread of pathogen-driven respiratory diseases. Regarding SARS-CoV-2 infection, exposure to fine PM (PM2.5, particles with an aerodynamic diameter < 2.5 μm) has been associated with increased incidence of the COVID-19 disease.To provide useful insights into the mechanisms through which PM might be involved in infection, we exposed human lung cells (A549) to PM2.5 and SARS-CoV-2, to evaluate the toxicological properties and the molecular pathways activated when airborne particles are combined with viral particles. Winter PM2.5 was collected in a metropolitan urban area and its physico-chemical composition was analyzed. A549 cells were exposed to SARS-CoV-2 concomitantly or after pre-treatment with PM2.5. Inflammation, oxidative stress and xenobiotic metabolism were the main pathways investigated. Results showed that after 72 h of exposure PM2.5 significantly increased the expression of the angiotensin-converting enzyme 2 (ACE2) receptor, which is one of the keys used by the virus to infect host cells. We also analyzed the endosomal route in the process of internalization, by studying the expression of RAB5 and RAB7. The results show that in cells pre-activated with PM and then exposed to SARS-CoV-2, RAB5 expression is significantly increased. The activation of the inflammatory process was then studied. Our findings show an increase of pro-inflammatory markers (NF-kB and IL-8) in cells pre-activated with PM for 72 h and subsequently exposed to the virus for a further 24 h, further demonstrating that the interaction between PM and SARS-CoV-2 determines the severity of the inflammatory responses in lung epithelial cells. In conclusion, the study provides mechanistic biological evidence of PM contribution to the onset and progression of viral respiratory diseases in exposed populations.

331 1H Nuclear magnetic resonance-based metabolomics of serum from growing beef steers following a combined viral bacterial respiratory disease challenge

331 1H Nuclear magnetic resonance-based metabolomics of serum from growing beef steers following a combined viral bacterial respiratory disease challenge

Recent developments in the therapeutics of SARS-CoV-2 infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly transmittable respiratory virus that causes COVID-19 disease. Since its emergence in the early 2000s, SARS has posed significant public health challenges and continues to be a concern. This review provides an overview of current treatment strategies for SARS-CoV and explores the potential utility of herbal molecules in combating this viral infection. The primary treatment approach for SARS-CoV has historically centered on supportive care, which includes oxygen therapy, mechanical ventilation, and antipyretic medications to manage symptoms. However, with the ongoing advancement of medical research and our evolving understanding of the virus, several antiviral drugs have been developed and repurposed to target SARS-CoV. Recent developments in the field of herbal medicine have drawn attention to the potential efficacy of natural compounds in the management of viral infections, including SARS. Herbal molecules, characterized by their diverse bioactive constituents, exhibit antiviral properties that could be harnessed to mitigate SARS symptoms and inhibit viral replication. Ocimum sanctum, Tinospora cordifolia, Zingiber officinale, Curcuma longa, Panax ginseng, and Aloe vera have been identified for their immunomodulatory effects. This review highlights promising herbal molecules such as quercetin, and curcumin, which have demonstrated antiviral effects in–vitro and in some preclinical studies. While current treatment strategies for SARS primarily rely on supportive care and antiviral medications, the exploration of herbal molecules presents an exciting avenue for potential adjunctive therapies. Further research is required to validate their efficacy, safety profiles, and mechanisms of action. A holistic approach that combines conventional medicine with herbal remedies may offer new insights into the treatment of SARS and other viral respiratory illnesses.

Estimating epidemic trajectories of SARS-CoV-2 and influenza A virus based on wastewater monitoring and a novel machine learning algorithm

The COVID-19 pandemic has altered the circulation of non-SARS-CoV-2 respiratory viruses. In this study, we carried out wastewater surveillance of SARS-CoV-2 and influenza A virus (IAV) in three key port cities in China through real-time quantitative PCR (RT–qPCR). Next, a novel machine learning algorithm (MLA) based on Gaussian model and random forest model was used to predict the epidemic trajectories of SARS-CoV-2 and IAV. The results showed that from February 2023 to January 2024, three port cities experienced two waves of SARS-CoV-2 infection, which peaked in late-May and late-August 2023, respectively. Two waves of IAV were observed in the spring and winter of 2023, respectively with considerable variations in terms of onset/offset date and duration. Furthermore, we employed MLA to extract the key features of epidemic trajectories of SARS-CoV-2 and IAV from February 3rd, to October 15th, 2023, and thereby predicted the epidemic trends of SARS-CoV-2 and IAV from October 16th, 2023 to April 22nd, 2024, which showed high consistency with the observed values. These collective findings offer an important understanding of SARS-CoV-2 and IAV epidemics, suggesting that wastewater surveillance together with MLA emerges as a powerful tool for risk assessment of respiratory viral diseases and improving public health preparedness.

Respiratory Viral Infections from 2015 to 2022 in the HIVE Cohort of American Households: Incidence, illness characteristics, and seasonality.

Viral respiratory illnesses are the most common acute illnesses experienced and generally follow a predicted pattern over time. The SARS-CoV-2 pandemic interrupted that pattern. The HIVE (Household Influenza Vaccine Evaluation) study was established in 2010 to follow a cohort of Southeast Michigan households over time. Initially focused on influenza, surveillance was expanded to include other major respiratory pathogens, and, starting in 2015, the population was followed year-round. Symptoms of acute illness were reported, and respiratory specimens were collected and tested to identify viral infections. Based on the known population being followed, virus-specific incidence was calculated. From 2015 to 2022, 1755 participants were followed in HIVE for 7785 person-years with 7833 illnesses documented. Before the pandemic, rhinovirus (RV) and common cold human coronaviruses (HCoVs) were the viruses most frequently identified, and incidence decreased with increasing age. Type A influenza was next but with comparable incidence by age. Parainfluenza and respiratory syncytial viruses were less frequent overall, followed by human metapneumoviruses. Incidence was highest in young children, but infections were frequently documented in all age groups. Seasonality followed patterns established decades ago. The SARS-CoV-2 pandemic disrupted these patterns, except for RV and, to a lesser extent, HCoVs. In the first two years of the pandemic, RV incidence far exceeded that of SARS-CoV-2. Longitudinal cohort studies are important in comparing the incidence, seasonality, and characteristics of different respiratory viral infections. Studies documented the differential effect of the pandemic on the incidence of respiratory viruses in addition to SARS-CoV-2.

Comparative Epidemiological and Clinical Outcomes on COVID-19 and Seasonal Influenza Hospitalized Patients during 2023.

COVID-19 and influenza are highly contagious respiratory viral diseases and priority global public health concerns. We conducted a retrospective observational study of COVID-19 and/or influenza hospitalized cases, during 2023. We identified 170 influenza cases, 150 COVID-19 cases and 3 co-infections. Overall, 29.10% of patients had at least one COVID-19 vaccine dose and 4.6% received the seasonal Flu vaccine. The demographic data found older patients in the COVID-19 group and a higher index of the comorbidities, mainly due to chronic heart diseases, hypertension, and diabetes. Fever, chills, and rhinorrhea were more frequently related to influenza, while cough was prevalent in COVID-19. Antibiotics were more used in influenza than COVID-19, either pre-hospital or in-hospital. The mortality rate within the first 30 days from the onset of the respiratory infection was higher in influenza compared to COVID-19. We concluded that the COVID-19 clinical picture in hospitalized patients is changing to influenza-like symptoms. The evolution is variable, related to chronic comorbidities, but influenza had more frequent severe forms. All through 2023, due to poor vaccination rates, COVID-19 and influenza have continued to cause numerous hospitalizations, and a new strategy for efficient vaccinations is required.