Objective: To evaluate risk factors for severe disease in children under 59 months of age hospitalized with respiratory syncytial virus (RSV) infection.Study design: We prospectively enrolled 1,096 cases of laboratory confirmed RSV infection during three consecutive RSV seasons in 2015–2018. Potential risk factors for severe disease were retrieved through patient questionnaires and linkage to national health registries. Need for respiratory support (invasive ventilation, bi-level positive airway pressure, or continuous positive airway pressure), and length of stay exceeding 72 h were used as measures of disease severity. Associations were investigated using multivariable logistic regression analyses. Multiple imputation was used to avoid bias and inference induced by missing data.Results: Risk factors associated with a need for respiratory support included age younger than 3 months of age [aOR: 6.73 (95% CI 2.71–16.7)], having siblings [aOR: 1.65 (95% CI 1.05–2.59)] and comorbidity [aOR: 2.40 (95% CI 1.35–4.24)]. The length of hospital stay >72 h was significantly associated with being younger than 3 months of age [aOR: 3.52 (95% CI 1.65–7.54)], having siblings [aOR: 1.45 (95% CI 1.01–2.08)], and comorbidity [aOR: 2.18 (95% CI 1.31–3.61)]. Sub-group analysis of children younger than 6 months of age confirmed the association between both young age and having siblings and the need for respiratory support.Conclusion: In a large cohort of children <59 months hospitalized with RSV infection, young age, comorbidity, and having siblings were associated with more severe disease.

Development of antibiotic resistance, a threat to global health, is driven by inappropriate antibiotic usage. Respiratory tract infections (RTIs) are frequently treated empirically with antibiotics, despite the fact that a majority of the infections are caused by viruses. The purpose of this study was to determine the prevalence of antibiotic treatment in hospitalized adults with viral RTIs, and to investigate factors influencing the antibiotic decision-making. We conducted a retrospective observational study of patients ≥ 18 years, hospitalized in 2015–2018 with viral RTIs. Microbiological data were taken from the laboratory information system and information on antibiotic treatment drawn from the hospital records. To investigate decisions for prescribing antibiotic treatment, we evaluated relevant factors such as laboratory and radiological results, in addition to clinical signs. In 951 cases without secondary bacterial RTIs (median age 73 years, 53% female), 720 (76%) were prescribed antibiotic treatment, most frequently beta-lactamase-sensitive penicillins, but cephalosporins were prescribed as first-line in 16% of the cases. The median length of treatment (LOT) in the patients treated with antibiotics was seven days. Patients treated with antibiotics had an average of two days longer hospital stay compared to patients with no such treatment, but no difference in mortality was found. Our study revealed that there is still a role for antimicrobial stewardship to further improve antibiotic use in patients admitted for viral RTIs in a country with relatively low antibiotic consumption.

To estimate age-specific incidence of medically attended respiratory syncytial virus (RSV) infections in hospitalised Norwegian children and describe disease epidemiology. Active prospective hospital surveillance for RSV in children <59 months of age was conducted during 2015-2018. All febrile children 12-59 months of age were enrolled, whereas children <12 months were enrolled based on respiratory symptoms regardless of fever. Surveillance data were linked to national registry data to estimate the clinical burden of RSV. Of the children enrolled, 1096 (40%) were infected with RSV. The highest incidence rates were found in children 1 month of age, with a peak incidence of 43 per 1000 during the 2016-2017 season. In comparison, children 24-59 months of age had an infection rate of 1.4 per 1000 during the same winter season. The peak season was during the 2016-2017 winter, with an incidence rate of 6.0 per 1000 children 0-59 months of age. In the study population a total of 168 (15%) of the infected children had pre-existing medical conditions predisposing for more severe disease. High infection rates were found in this population. Children with comorbidities showed high hospital contact rates, but the majority of children in need of medical attention associated with RSV infection were previously healthy.

Background: The clinical features and outcomes of viral respiratory tract infections (RTIs) in adults have not been thoroughly studied, especially the respiratory syncytial virus (RSV) disease burden. It has become apparent that outbreaks of RSV in the elderly are associated with increased hospitalization rates. However, little data exists on the severity of such viral RTIs in adults, particularly the need for hospitalization, respiratory support and intensive care.Methods: We conducted a retrospective observational single-center study at Østfold Hospital Trust, Norway, during three winter seasons 2015–2018. Patients ≥18 years with either influenza A, influenza B, RSV A/B, human metapneumovirus, parainfluenza virus 1–4 or adenovirus detected in respiratory specimens were included, if they were hospitalized 14 days prior or following the detection date, with signs of RTI. Hospital records on treatment and outcome were investigated, as well as mortality of all causes up to 30 days from discharge.Results: Of the 1222 infection events that were included, influenza A was the most frequent virus detected (39%), while 179 infection events (14.6%) were due to RSV. Influenza B counted for 24% of the infection events, human metapneumovirus 13%, parainfluenza virus 9% and adenovirus 1%. Patients admitted with RSV more often suffered from COPD and congestive heart failure than patients with influenza A. In addition, RSV patients were overrepresented in the urgent response NEWS score (National Early Warning Score) category ≥5. RSV patients also showed signs of more severe inflammation, with WBC ≥11.1 × 10⁹/L and CRP >100 mg/L, and they were more often treated with antibiotic agents during their hospital stay. However, we found no differences in the need for ICU admission or mortality.Conclusion: Patients with RSV had more often high values for markers of inflammation and elevated NEWS score when compared to patients hospitalized with other common respiratory viruses. Taken into account that they suffered more frequently from comorbidities like COPD, these patients needed hospitalization more urgently. These findings highlight the need for further investigations on RSV disease in adults and the elderly.

Background and aims: Respiratory tract infections (RTIs) cause considerable morbidity and mortality in all age groups, but the epidemiology and role of several of the viral RTIs in the adult and elderly patients are still unclear, as is the extent of prehospitalization antibacterial drug use in this population.Methods: We conducted a three‐year (2015‐2018) observational study of viral RTIs in hospitalized patients in a 500‐bed hospital in Southeastern Norway, including all patients ≥18 years with RTI symptoms where one of the following viral agents was detected in a respiratory specimen (Seegene Allplex): Influenza A/B, RSV A/B, human metapneumovirus (hMPV), adenovirus and parainfluenza virus 1‐4. Viral findings, demographical data, and information on prehospital antibiotic prescriptions were recorded.Results: In 1182 patients 1222 viral infection events occurred. The mean patient age was 69.6 years, and 53% were females. Influenza virus A/B (63%), RSV A/B (15%) and hMPV (13%) were the most common agents detected. The proportional burden of influenza A H1 was found to be relatively high (65%) in the age groups <69 years, compared to older patients (P = .001, chi‐square).As many as 20% of the patients had been treated with antibiotics prior to admission, with the lowest rate for influenza A H3 group at 17% (P = .036, chi‐square), and highest for the RSV group at 28% (P = .004, chi‐square).Oseltamivir was prescribed prior to hospitalization in only 3 cases (0.2%).Conclusions: We found a high rate of prehospital antibiotic prescription in adults hospitalized with viral RTIs, warranting better stewardship programs to tackle the increasing antibiotic resistance problem.

Background: Up to 60% of the antibiotics prescribed to patients hospitalized with seasonal influenza are unnecessary. Procalcitonin (PCT) has the potential as an antimicrobial stewardship program (ASP) tool because it can differentiate between viral and bacterial etiology. We aimed to explore the role of PCT as an ASP tool in hospitalized seasonal influenza patients. Methods: We prospectively included 116 adults with seasonal influenza from two influenza seasons, 2018–2020. All data was obtained from a single clinical setting and analyzed by descriptive statistics and regression models. Results: In regression analyses, we found a positive association of PCT with 30 days mortality and the amount of antibiotics used. Influenza diagnosis was associated with less antibiotic use if the PCT value was low. Patients with a low initial PCT (<0.25 µg/L) had fewer hospital and intensive care unit (ICU) days and fewer positive chest X-rays. PCT had a negative predictive value of 94% for ICU care stay, 98% for 30 days mortality, and 88% for bacterial coinfection. Conclusion: PCT can be a safe rule-out test for bacterial coinfection. Routine PCT use in seasonal influenza patients with an uncertain clinical picture, and rapid influenza PCR testing, may be efficient as ASP tools.