Background: Antibiotics are prescribed frequently for upper respiratory tract infections (URTIs) despite the fact that most of them do not require antibiotics. This over-prescription contributes to antibiotic resistance which is a major health problem. Physicians perceive that patients’ expectations influence their antibiotic prescribing practice. Methods: As the first phase of the thesis, we conducted a systematic review to determine the effectiveness of patient-oriented interventions to reduce unnecessary use of antibiotics for URTIs. As the second phase, we conducted a qualitative descriptive study to explore patients’ views about URTIs and identify ways they manage them by using semi-structured interviews based on Common Sense-Self-Regulation Model (CS-SRM). Results: Our systematic review included 14 studies which based on their interventions were classified into two major categories: delayed prescriptions and patient/public information and education interventions. Our meta-analysis revealed that almost all studies with delayed prescription significantly reduced use of antibiotics for URTIs. Our subgroup analysis showed that prescriptions that were given at a later time and prescriptions that were given at the index consultation had similar effects regarding antibiotic use. The small number of included studies in the patient/public information and education group did not allow us to make a definite conclusion on their effectiveness. For the qualitative study, 15 individuals were interviewed. almost all participants mentioned that they only visited their doctor if their symptoms got progressively worse and they could no longer self-manage URTI symptoms. When visiting a doctor, most participants reported that they expected to receive an examination and an explanation for their symptoms. Discussion: Patient-oriented interventions (especially delayed prescriptions) may be effective in reducing antibiotic use or prescription for URTIs in patients. Further research is needed to investigate the costs and feasibilities of implementing these interventions as part of routine clinical practice. Our participants reported good knowledge regarding the likely lack of benefit from antibiotics for URTIs. The results suggest a discrepancy between our participants’ reported reasons for visiting doctors and doctors’ perceptions about patients’ reason for their visit identified in previous studies. Focusing on interventions that facilitate the communication between patients and doctors, instead of providing more education to public may help in reducing the use of unnecessary antibiotics.

Background: Humanmilk oligosaccharides (HMOs) support and concurrently shape the neonatal immune system through various mechanisms. Thereby, they may contribute to lower incidence of infections in infants. However, there is limited evidence on the role of individual HMOs in the risk of otitis media (OM), as well as lower and upper respiratory tract infections (LRTI and URTI, respectively) in children up to 2 years. Objective: To investigate whether individual HMO concentrations measured at 6 weeks of lactation were associated with risk of OM, LRTI or URTI up to 2 years in breastfed infants. Associations with OM, LRTI and URTI were determined for the most prominent human milk oligosaccharides including 13 neutral, partly isomeric structures (trioses up to hexaoses), two acidic trioses, and lactose. Design: HMO measurements and physician reported data on infections were available from human milk samples collected at 6 weeks postpartum (n = 667). Associations of HMOs with infections were assessed in crude and adjusted models using modified Poisson regression. Results: Absolute concentrations (median [min, max], in g/L) of 2′-fucosyllactose (2′-FL) tended (p = 0.04) to be lower, while lacto-N-tetraose (LNT) was higher in the milk for infants with OM in the 1st year of life (p = 0.0046). In the milk of secretor mothers, LNT was significantly higher in the milk for infants with OM (RR [95% CI]: 0.98 [0.15, 2.60]) compared to infants without OM (RR [95% CI]: 0.76 [0.14, 2.90]) at 1 year (p = 0.0019). No statistically significant milk group differences and associations were observed for OM, LRTI, and URTI (p > 0.0031). Conclusion: Our findings suggest that neither prominent neutral individual HMOs (ranging from 2′-FL to LNDFHs) nor acidic human milk sialyllactoses or lactose are significantly associated with a reduced or increased risk of infections in infants up to 2 years of age. Further research is needed to determine whether specific HMOs could potentially reduce the incidence or alleviate the course of distinct infections in early life.

<p><strong>Background</strong>: Human rhinovirus/enterovirus (HRV/ENT) infections are commonly identified in children with acute respiratory infections (ARIs), but data on their clinical severity remains limited. We compared the clinical severity of HRV/ENT to respiratory syncytial virus (RSV), influenza A/B (FLU) and other common respiratory virus in children.</p> <p><strong>Methods</strong>: Retrospective study of children with ARIs and confirmed single positive viral infections on mid-turbinate swabs by molecular assays. Outcome measures included hospital admission and, for inpatients, a composite end-point consisting of intensive care admission, hospitalization greater than 5 days, oxygen requirements or death.</p> <p><strong>Results</strong>: A total of 116 HRV/ENT, 102 RSV, 99 FLU and 64 other common respiratory viruses were identified. Children with single HRV/ENT infections presented with significantly higher rates of underlying immunosuppressive conditions compared to those with RSV (37.9% vs 13.6%; p</p> <p><strong>Conclusions</strong>: Children with HRV/ENT had a more severe clinical course than those with RSV and FLUA/B infections and often had significant comorbidities. These findings emphasize the importance of considering HRV/ENT infection in children presenting with severe acute respiratory tract infections.</p> / Master of Science (MSc)